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larose - 8 months ago - Views: 176 - Name: Wildlife Note Series
1 Pennsylvania Game Commission Wildlife Notes Envirothon students will be able to identify the animals described in the Wildlife Notes listed below. 1. Bats 27. Mink & Muskrats 2. Beaver 28. Northern Cardinal, Grosbeaks, Indigo Bunting, and Dickcissel 3. Black Bear 29. Opossum 4. Blackbirds, Orioles, Cowbird, and Starling 30. Owls 5. Blue Jay 31. Pheasants 6. Bobcat 32. Porcupine 7. Canada Goose 33. Puddle Ducks 8. Chickadees, Nuthatches, Titmouse, and 34. Raccoon Brown Creeper 35. Raptors 9. Chimney Swift, Purple Martin, and 36. River Otter Swallows 37. Ruffed Grouse 10. Common Nighthawk and Whip-Poor-Will 38. Shrews 11. Cottontail Rabbit 39. Sparrows and Towhees 12. Crows and Ravens 40. Snow Goose 13. Diving Ducks 41. Squirrels 14. Dove 42. Striped Skunk 15. Eagles and Osprey 43. Tanager 16. Eastern Coyote 44. Tundra Swan 17. Elk 45. Vultures 18. Finches and House Sparrow 46. Weasels 19. Fisher 47. White-tailed Deer 20. Flycatchers 48. Wild Turkey 21. Foxes (Red and Gray) 49. Wood Duck 22. Gray Catbird, Northern Mockingbird, 50. Wood Warbler and Brown Thrasher 51. Woodchucks 23. Heron Family 52. Woodcock 24. Kingfisher 53. Woodpeckers 25. Mallard Duck 54. Wrens 26. Mice and Voles
2 Wildlife Note — 35 LDR0103 Bats Big Brown Bat by Chuck Fergus Bats are the only mammals that fly. Their wings are zation occurs. The young, born in summer, are naked, thin membranes of skin stretched from fore to hind legs, blind and helpless. They are nursed by their mothers and and from hind legs to tail. The name of their order, by six weeks of age, most are self-sufficient and nearly Chiroptera, means "hand-winged." Their long, slender adult size. finger bones act as wing struts, stretching the skin taut The reproductive potential of bats is low. Most bats, for flying; closed, they fold the wings alongside the body. including the smaller species, usually bear a single young Pennsylvania bats range in size from the hoary bat per year; the larger species may have up to four. There is (length, 5.1 - 5.9 inches; wingspread, 14.6 - 16.4 inches; only one litter per year. weight, 0.88 - 1.58 ounces) to the pygmy bat, or None of Pennsylvania's bats fly during the brighter pipistrelle (length, 2.9 - 3.5 inches; wingspread, 8.1 - 10.1 hours of daylight, preferring to make their feeding flights inches; weight, 0.14 - 0.25 ounces). Nine species of bats in late afternoon, evening and early morning. However, occur in Pennsylvania; two others are rare visitors from it's not unusual to see a bat flying during the day. Roost the South. disturbance and heat stress may cause bats to take wing All Pennsylvania bats belong to family during daylight hours. During the day, they roost — sin- Vespertilionidae, and are also known as evening bats or gly, in pairs, in small groups, or in large concentrations, common bats. They are insect eaters, taking prey on the depending on the species. They seek out dark, secluded wing. Often they feed over water, and some species oc- spots such as caves, hollow trees and rock crevices. They casionally land and seize prey on the ground. A bat con- may also congregate in vacant buildings, barns, church sumes up to 25 percent of its weight at a single feeding. steeples and attics; some hide among the leaves of trees. The eyes of our bats are relatively small, but their ears They hang upside down, by their feet. are large and well developed. Bats can see quite well, In fall, winter and early spring, insects are not readily but unique adaptations help them fly and catch prey in available to bats in Pennsylvania and other northern total darkness. While in flight, a bat utters a series of states. At this time, three species migrate south; six oth- high-pitched squeaks (so high, in fact, they are almost ers hibernate underground, usually in caves. always inaudible to humans), which echo off nearby ob- Bats are true hibernators. Throughout winter, they eat jects — bushes, fences, branches, insects — and bounce nothing, surviving by slowly burning fat accumulated back to the bat's ears. These sound pulses may be only during summer. A hibernating bat's body temperature 2.5 milliseconds in duration. Split-second reflexes help drops close to the air temperature; respiration and heart- the creature change flight direction to dodge obstruc- beat slow; and certain changes occur in the blood. Bats tions or intercept prey. can be roused fairly easily from hibernation, and often A bat will use its mouth to scoop a small insect out of are able to fly 10 to 15 minutes after being handled. Most the air. A larger insect is often disabled with a quick bite, favor cave zones having the lowest stable temperature cradled in a basket formed by the wings and tail, and above freezing. During winter, bats may awaken and move carried to the ground or to a perch for eating. If an insect about within a cave to zones of more optimum tempera- takes last second evasive action, the bat may flick out a ture. In many caves, bats of several species hibernate wing, nab its prey, and draw the insect back to its mouth. together. Bats have sharp teeth to chew their food into tiny, easily Perhaps because of their nocturnal nature, secretive digested pieces. habits and unique appearance — not to mention Most bats mate in late summer or early fall, although supersitions — bats have long been misunderstood and some breed in winter. The male's sperm is stored in the sometimes feared, and many misconceptions exist about female's reproductive system until spring, when fertili- them. They include: Bats are prone to rabies; their drop-
3 pings are a dangerous source of tuberculosis and other diseases; they are aggressive and often attack people; they are dirty and ridden with lice. Bats are no more apt to contract rabies than other warm-blooded animals. (People should not, however, handle bats, especially those found on the ground or in the open during the day.) There is no evidence to sug- gest that bats — or their droppings, called "guano" — Little Brown Bat transmit tuberculosis to man. A host of scientific studies indicate that healthy bats do not attack people, and even Indiana Bat rabid bats rarely become aggressive. Bats need to keep themselves extremely clean to fly. They host no more and is greatest just before hibernation. Females are parasites than other animals, and parasites that do af- slightly larger than males. Color: a rich brown approach- flict bats are very specialized and rarely pose problems ing bronze, usually with a dark spot on the shoulders. to humans. Histoplasmosis, caused by a soil fungus that The fur is dense, fine and glossy; the wings are black and can grow in accumulated bird and bat droppings, does bare. not, as a rule, survive in hot dry attics. However, as a This bat eats a wide variety of flying insects, includ- precaution, it's recommended that you wear a respirator ing nocturnal moths, bugs, beetles, flies and mosquitoes. when stirring up dust in bat quarters or cleaning out large Insects are regularly caught with the wing or tail mem- accumulations of droppings. brane, and transferred to the mouth. An individual The colonial bats may congregate at favorite roost- emerges from its day roost at dusk, and usually seeks a ing sites, often in buildings. While these bats do no real body of water, where it skims the surface for a drink, and harm to human occupants, their droppings, odor and then hunts insects. Bats examined within an hour of tak- noise may become a nuisance. To exclude bats correctly ing flight often have full stomachs weighing one-fifth of may take two years. The first summer you should watch their body weight. The little brown bat makes several the home at dusk to see where the bats are exiting. Try to feeding flights each night, and is capable of catching get a count of the number of bats. If possible, erect a 1,200 insects per hour. A nursing female may eat her own well-placed bat box of good design before August.The weight in insects nightly. box should be large enough to accommodate the bats In October and November, bats leave their summer you plan to evict. When the bats leave in the fall, seal all roosts and move to tunnels, mine shafts and caves. Here, entrances. Next spring, when they return, they are likely clinging to the ceilings and clustered against one another, to move into the bat box, rather than search for a new they hibernate, until they emerge in April and May. They way into your home, or your neighbor's. Do not seal bats return to the same hibernation and summer roost sites out during June or July because you will trap flightless year after year. young inside. Females disperse from the hibernation roosts and Exterminating is a questionable practice. Poisons used gather in summer nursery colonies of just a few to 1,000 on bats can be dangerous to humans, and may cause sick- or more individuals in attics, barns and other dark, hot ened bats to scatter and fall to the ground, where they retreats. Males are solitary, roosting in hollow trees, un- are more likely to come into contact with people and der loose bark, behind loose siding and shingles and in pets. Currently no pesticides are approved for use on bats. rock crevices. Reputable pest control operators use bat exclusion tech- A single young is born to each female in June or early niques. July. After four weeks, the young bat is fully grown, and To counterbalance their low reproductive rates, bats ready to leave the colony. Females mature sexually at are relatively long-lived. Some have been banded, re- about 8 months of age, while males mature in their sec- leased and recaptured more than 30 years later. Because ond summer. Little brown bats may live more than 30 they feed in mid-air and are active at dusk and at night, years. bats are not often caught by predators. Owls and hawks take some, as do housecats, raccoons and foxes. Rat Indiana Bat ) — The Indiana bat re- Myotis sodalis ( snakes occasionally eat roosting bats. Other causes of sembles the little brown bat, but has a pinkish cast to its mortality include cave floodings and accidents. fur, giving it a light purple-brown coloration. Length, The greatest threat to bats comes from humans. In 2.9 - 3.7 inches; wingspread, 9.4 - 10.3 inches; weight, winter, hibernating bats may be aroused by people ex- 0.18 - 0.28 ounces. Sexes are equal in size. ploring caves; repeated disturbances force bats to squan- Indiana bats probably roost in trees in summer; and der precious calories needed for overwintering. Caves they do not commonly roost in buildings. In winter, some may be flooded by dams, or dynamited shut. Some scien- 97 percent of the total species population hibernates in tists suspect that widespread use of pesticides also harms certain large caves in Missouri, Kentucky, Indiana and bat populations. Illinois. Pennsylvania is on the fringe of the species' range. Indiana bats have been found wintering in 12 sites ) — Pennsylvania's ( Little Brown Bat Myotis lucifugus (caves, as well as abandoned mines and railroad tunnels), most common bat, the little brown, is found statewide. and are monitored regularly by the Game Commission, Length, including tail, is 3.1 - 3.7 inches; wingspread, and it is on the federal endangered species list. 8.6 - 10.5 inches; weight ranges from 0.25 - 0.35 ounces, The Indiana bat hibernates in clusters of about 250
4 lated bats. The small-footed bat waits until November to bats per square foot on the ceilings and side walls of caves. enter caves for hibernating, and emerges in March. It hi- In this formation, it is vulnerable to disturbance by cave bernates in narrow cracks in the wall, floor or roof, singly explorers: when a bat on the edge of the cluster is awak- and in groups of up to 50 or more. It usually stays close to ened, it moves about, starting a ripple of activity that entrances where the temperature is just above freezing. spreads throughout the group. A winter of repeated dis- turbances causes bats to burn vital fat stores, and they may run out of energy before spring. Females of this species are believed to bear a single young in late June. Feeding habits are probably similar to those of the little brown bat. Silver-haried Myotis septentrionalis ( )— Northern Long-Eared Bat Bat Similar in size and color to the little brown bat, the north- ern long-eared bat may be distinguished by its longer tail and narrower and longer ears. It ranges in forested areas throughout the state, but is much less common than the little brown bat; its distribution is considered local and irregular. Length, 3.0 - 3.7 inches; wingspread, 9.0 - 10.7 inches; weight, 0.25 - 0.32 ounces. Biologists have learned little of the ecology and be- havior of the northern long-eared bat, although they sus- pect feeding habits are similar to those of the little brown. Long-eared bats roost singly or in small colonies in caves, behind window shutters, under loose tree bark and in cliff crevices. Females gather in nursery colonies in attics, barns and tree cavities. Probably a single young is born in July. Long-eared bats return to caves in fall, often sharing Eastern space with little brown bats, big brown bats and pipistrelle Pipistrelle bats. ( ) — A me- Lasionycteris noctivagans Silver-Haired Bat Northen dium-size bat: length, 3.7 - 4.5 inches; wingspread, 10.5 - Long-earred 12.1 inches; weight, 0.25 - 0.35 ounces. The fur is soft and long; the sexes are colored alike, blackish-brown tipped Bat with white, for a bright, frosted appearance. The silver-haired bat inhabits wooded areas bordering lakes and streams. It roosts in dense foliage, behind loose bark, or in a hollow tree — rarely in a cave. It begins feeding earlier than most bats, often before sunset. Sil- ver-haired bats do not hibernate in Pennsylvania, migrat- ing farther south. In summer, a few may breed in the cooler, mountainous sections of the state, but most go farther north. Small Footed Bat ) — The Pipistrellus subflavus ( Eastern Pipistrelle pipistrelle is also called the pygmy bat because of its small Small-Footed Bat ( Myotis leibii ) — Also known as size: length, 2.9 - 3.5 inches; wingspread, 8.1 - 10.1 inches; Leib's bat, this species is one of the smallest in North weight, 0.14 - 0.25 ounces. Its fur is yellowish brown, America: length, 2.8 - 3.3 inches; wingspread, 8.3 - 9.7 darker on the back. The back hairs are tricolored: gray at inches; weight, 0.18 - 0.28 ounces. As the name implies, the base, then a band of yellowish brown, and dark brown it has a very small foot when compared with other bats. at the tip. When viewed from the front, the bat has a distinct black Pipistrelles take wing early in the evening and make mask that stretches from ear tip to ear tip. In Pennsylva- short, elliptical flights at treetop level. In summer, they nia, it is rare, and the population is thought to be de- inhabit open woods near water, rock or cliff crevices, creasing; it is classified as a threatened species on the state buildings and caves. They hibernate from September list. Very little is known about this bat's summer habitat through April or early May, deep inside caves and away and lifestyle. from the openings, in zones where the temperature is about The small-footed bat resembles the little brown bat, 52 to 55 F. They sleep soundly, often dangling in the same but has a golden tint to its fur. Feeding and breeding hab- spot for months. its probably parallel those of the other small, closely re- Pipistrelles eat flies, grain moths and other insects.
5 They breed in November, and young — usually two per litter — are born in June or July. Pipistrelles live up to 15 years, and are found throughout Pennsylvania, except in the southeastern corner. Eptesicus fuscus ( ) — Second in size to Big Brown Bat the hoary bat, the big brown is 4.1 - 4.8 inches long; wing- spread, 12.1 - 12.9 inches; weight, 0.42 - 0.56 ounces. The fur is dark brown, and the face, ears and flight membranes are blackish. This common bat ranges throughout the state Hoary in diverse habitats: attics, belfries, barns, hollow trees, Bat behind doors and shutters, in city and country. Big brown bats fly at dusk, and generally use the same feeding grounds each night. They fly in a nearly straight course 20 - 30 feet in the air, often emitting an audible chatter. Major foods include beetles and true bugs (junebugs, stinkbugs and leafhoppers) many of which are major agricultural pests. A colony of 150 big brown bats can eat enough cucumber beetles during the summer to protect farmers from 18 million rootworm larvae. Among the last bats to enter hibernation, big brown bats seek out caves, buildings, mines and storm sewers in October, November or December. They hang close to the mouths of caves, and emerge in March and April. Females bear young in June, usually two per litter. As young ma- ture and leave the nursery colony, adult males enter and take up residence. Big brown bats have lived up to 19 years in the wild. Red Bat ( Lasiurus borealis ) — A bright rusty coat and Red Bat long, pointed wings distinguish this species. Length is 3.7 - 4.8 inches; wingspread, 11.3 - 12.9 inches; and weight, 0.28 - 0.49 ounces. Individuals roost singly in trees (ex- spring, they return and raise young. The young are born cept for females with young), often on forest edges, in from mid-May to early July, usually two to a litter. Fe- hedgerows, and shrubby borders; they seem to prefer males have two pairs of breasts and sometimes have three American elms. Rarely do they use caves or buildings. or four pups in a litter. The female gives birth while hang- Red bats start flying early in the evening, preying on ing in a tree. Young grow rapidly and are able to fend for moths, flies, bugs, beetles, crickets and cicadas, which they themselves in about a month. take from air, foliage and ground. Strong fliers, red bats and (Lasiurus seminolus) Note: The Seminole Bat are considered migratory, although little is known about Evening Bat (Nycticeius humeralis) have been found a few their patterns. The sexes may migrate separately. Red bats times in Pennsylvania, but are not considered regular resi- start south in September or October, flying at night. They dents. can withstand body temperatures as low as 23 F. Homeowners having problems with bats may request Females bear l - 5 young (usually 2 - 3) in their tree- the booklet, A Homeowner's Guide to Northeastern Bats top roosts. For the first few days, the young remain cling- and Bat Problems , by Lisa M. Williams-Witmer and Mar- ing to their mother when she flies out on hunts. Young are garet C. Brittingham, Publication Distribution Center, able to fly at 3 - 4 weeks, and are weaned when 5 - 6 weeks Pennsylvania State University, 112 Agricultural Admin- old. Longevity is about 12 years. The red bat ranges across istration Building, University Park, PA 16802. A video, Pennsylvania. The Season of the Bat , is available from: Wild Resource Conservation Fund, P.O. Box 8764, Harrisburg, PA 17105- ) — The largest bat of the Lasiurus cinereus ( Hoary Bat 8764 (Phone — 717-783-1639). Eastern forests, the hoary is 5.1 - 5.9 inches long; has a 14.6 - 16.4-inch wingspread; and weighs 0.88 - 1.58 ounces. The fur is dark brown, heavily tinged and white. The species ranges across the state, but is uncommon. Wildlife Notes are available from the Hoary bats roost in trees — they prefer conifers, but Pennsylvania Game Commission also use deciduous trees — in woods, forest edges and farm- Bureau of Information and Education land. They choose protected sites 12 - 40 feet above the Dept. MS, 2001 Elmerton Avenue ground. Strong, swift fliers, they take to the air later than Harrisburg, PA 17110-9797 most other bats. They prey mostly on moths, but also take www.pgc.state.pa.us beetles and mosquitoes. Hoary bats migrate to warmer climates in winter. In An Equal Opportunity Employer
6 cinnamon-color. (In other parts of its range, Ursus americanus may be brown, whitish, or bluish-gray, but the majority are black.) The body is glossy black, the muzzle tinged with tan. Often a bear will have on its chest a white mark, sometimes in a prominent "V." The fur is thick, long and fairly soft. Sexes are colored alike. Wildlife Note — 29 Bears walk in a shuffling, flat-footed manner. Each foot has five toes, each with a curved claw. Extremely agile for their size, bears sometimes stand erect on their hind feet to see and smell better. Top speed is 30 miles per hour over a short distance. Black bears climb easily and swim well. Black bears have an acute sense of smell, but their Black vision is poor. Hearing is not believed to be acute. They occasionally growl or "woof," and when injured, sob and bawl. Sows communicate to their cubs with low grunts, huffs and mumbles. Bears are mainly nocturnal, but they sometimes feed Bear and travel by day. Alert and wary, they tend to avoid open areas. Individuals are solitary. While most bears will run from a human, a female with cubs should be re- spected, and on rare occasions might actually attack if she feels her young are in danger. Bears that become ac- by Chuck Fergus customed to humans (as in a park or garbage dump set- ting) are less likely to run away, making them potentially much more dangerous. One of Pennsylvania's premier big game animals is the Bears find food mainly by scent. They are opportunis- Ursus americanus. The species ranges through black bear, tic feeders, with a largely vegetarian diet. Common foods much of forested North America from Mexico to Alaska are fruit (including large amounts of many kinds of ber- and from Florida to northern Canada. In different regions, ries), mast (acorns and beechnuts), succulent leaves of black bears exhibit different life patterns, denning times, hardwoods, grasses, insects (including eggs and larvae), tolerance of human activity, habitat preferences, home plant roots, amphibians, reptiles, small mammals, fish, range, reproduction behavior, pelt coloration and even carrion and garbage. An occasional bear runs afoul of size and weight. humans by preying on pigs, goats or sheep; by eating corn; by raiding campers' food stores; and by destroying hon- Biology eybee colonies (beekeepers with such problems should protect their hives with electric fences). Bears drink wa- Bears are powerfully built animals. Adults are 50 to ter frequently, and in hot weather they wallow in streams. 85 inches in length, including a three- to five-inch tail. In autumn, bears eat heavily to fatten themselves for They stand about 30 inches at the shoulder and weights winter. The winter den may be a hollow tree or log, an range from 140 to 400 pounds, with some individuals excavation or a crevice in a rock ledge; it may be a "nest" weighing more than 800 pounds. Males, sometimes called on top of the ground, or under fallen trees or brush, in a boars, tend to be considerably larger and heavier than cavity under a large rock or beneath the roots of a tree; females (sows). or it may be in a drainage culvert or a depression dug in Most Pennsylvania bears are black, although a few are
7 the ground. Some bears line termates. The female pro- their dens with bark, grasses or tects them, sending them up trees if danger threatens. Males leaves. Females often select more sheltered sites than males. occasionally kill and eat cubs. Males den alone, as do pregnant In most cases, cubs den with their mothers for their first winter. The fam- females (they give birth in the den). ily group disbands the following sum- Females with first-year cubs den with their young. mer, when the female again is ready to breed. A female generally raises In winter, bears den up and be- come dormant. They lapse into one litter only every two years. Most females breed for the first and out of a deep sleep, from which they may be roused. Body time when 2½ years old. temperature is not drastically re- Mortality factors include hunting, damage control and duced. Respiration and heart rate highway kills. Bears host ticks might decline noticeably. They do not urinate or defecate and internal parasites. In the wild, a rare individual might while dormant. Bears in poor live to 25 years. condition den for shorter pe- riods than those in better shape. On warm, late-winter Population days, they may emerge to look for food. In some areas, bears create trails while covering the In Pennsylvania, bears are found in large forested ar- nightly circuits they run. Individuals may scar prominent eas statewide. They are not typically found in large ur- trees with claw and tooth marks; these "bear trees" may ban and agricultural areas. The total population currently mark a territory or signal availability during mating sea- is estimated to be 15,000. son. Periodic harvesting, through hunting, helps minimize Bears mate from early June to mid-July. It is generally bear problems in agricultural areas — honeybee, live- accepted that they are polygamous. The male does not stock, crop destruction — and, in suburban areas. help rear young. Habitat Females give birth to cubs in January while in the win- ter den. Litter sizes range from one to five, with three Bears inhabit wooded country. In spring and summer, most frequent in Pennsylvania. Newborns are covered they frequent openings to feed on fresh vegetation and with fine dark hair, through which their pink skin shows. berries; in fall, they occupy dense, regenerating clearcuts They are about nine inches long and weigh 10 to 16 and mountain laurel thickets. In the northeast — a ounces. Their eyes and ears are closed. pocket of prime bruin habitat — bears favor brushy Cubs nurse in the den. After about six weeks, their swamps with rhododendron, blueberry and spruce. They eyes open. In about two more weeks, also inhabit mixed hardwood forests, especially where they walk. They leave the den underbrush is thick. when three months old, are Bears range over large areas. Movement is affected by weaned by seven months, and by food availability, breeding activities and human distur- fall usually weigh 60-100 pounds. bances. Although bears show remarkable adaptability in Bears traveling in groups in au- living close to humans, their numbers decline as their tumn are usually females and their habitat shrinks. Protecting suitable wild lands, especially cubs. those containing wetlands, is probably the single best Cubs are playful, romping in habitat management tool. water and wrestling with their lit- Wildlife Notes are available from the Pennsylvania Game Commission Bureau of Information and Education Dept. MS, 2001 Elmerton Avenue Harrisburg, PA 17110-9797 www.pgc.state.pa.us An Equal Opportunity Employer
8 Wildlife Note — 14 LDR0103 Beaver by Chuck Fergus The beaver, , is North America's larg- Castor canadensis a rudder; the tail also supports a beaver when it sits erect est rodent. Before European colonists arrived, the spe- or gnaws a tree on dry land. A sharp slap of the tail on cies was plentiful from the Mexican border to the Arc- water is a signal warning other beavers of danger. tic. Beaver fur is thick and considered valuable; untanned A beaver's front feet are remarkably dextrous. They pelts brought four dollars each in the early 1800s, when have long claws and are used for digging, handling food the skins were used to make top hats and to trim clothes. and working on dams. The thumb is small and weak, but Tremendous demand for beaver fur sent trapping expe- the little finger is strong and has taken over the thumb's ditions throughout the unexplored West, stimulating role. The hind feet, broad and webbed between the toes, expansion of the new American nation. propel the animal through the water. The second claw By the end of the nineteenth century, uncontrolled from the outside on each hind foot is double (or split) trapping had eliminated beavers in Pennsylvania and and is used for grooming. other states, but today this aquatic furbearer is back. A beaver's vision is weak, but its hearing and sense of Aided by modern wildlife management and its own pro- smell are acute. Most food is located by smell. Beavers lific breeding potential, the beaver has repopulated a are slow on dry land but quite mobile in the water. A great deal of its former range. beaver can stay submerged up to 15 minutes; membrane Today, beavers are found throughout Pennsylvania. valves seal the ears and nostrils while it's submerged. The highest concentrations are found in the northern Both males and females possess musk sacs, or castors, counties, often in remote territory and always in areas which produce an oily, heavily-scented substance called with plentiful, constant water sources. Using branches, "castoreum," which the animals use to mark territories. mud and rocks, beavers build dams and lodges on streams Commercially, castoreum has been used as an ingredient and creeks, and along the edges of lakes and rivers. Bea- for some medicines and perfumes, not to mention trap- vers are shy and mainly nocturnal, but people interested ping lures. Beavers have two other sacs, one on each side in catching a glimpse of a beaver may get lucky by stak- of the urogenital opening, which secrete an oil. The ani- ing out a beaver pond in the early morning and near sun- mal rubs this oil into its fur to repel water. down. Because its front teeth never stop growing, a beaver must con- Biology tinually cut wood to offset incisor Adult beavers weigh 40-60 pounds and grow up to 40 growth. The up- inches in length. (An extinct giant beaver of the Pleis- per and lower tocene era was the size of a bear.) They have blunt heads, incisors are the short necks and legs, and stocky bodies. The coat is glossy primary cutters. tan to dark brown above, paler below; it consists of dense A beaver can underfur covered with longer guard hairs. The thick pelt close its lips be- and deposits of body fat insulate the animal and allow it hind its incisors to remain in the water many hours at a time. to gnaw on and A beaver's tail is trowel-shaped, 8-12 inches long and transport sap- five or six inches wide. It has a scaly, leathery covering. lings while un- When the animal swims, it uses its tail as a propeller and derwater.
9 impregnable to predators that might visit. Along fast, Beavers eat vegetable matter. They prefer soft plant turbulent streams — or creeks and rivers too wide to dam foods, including grasses, ferns, mushrooms, duckweed, al- — beavers either burrow deep into the bank or build gae, and the leaves, stems and roots of water plants such lodges at the water's edge. The entrance to a lodge as cattails and water lilies. When soft foods are avail- (whether it's on the bank or in the middle of a pond) is able, beavers cut down few trees unless they're needed always below water level, while the den is dry and above for dam or lodge repair. water. They also eat the bark, twigs and buds of aspen, maple, Beavers are generally congenial, although rivals fight willow, birch, black alder and black cherry trees. In au- during the February-March breeding season. Females are tumn, beavers cut branches, twigs and small logs, carry believed to be monogamous, while some authorities think them to the bottom of their home ponds, and anchor them males may breed more than one female. A female usu- in the mud. Then, when the pond freezes over in the win- ally drives her family out of the lodge when she nears the ter, they still have access to food. They may also remove end of the 12-week gestation period. In April or May, some sticks from the dam to lower the water and create she bears 3-6 (usually 4 or 5) young called "kits." New- air space under the ice. borns weigh about a pound; their eyes are open, their Beavers fell trees to get at the teeth erupted, and they are fully furred. If an emergency higher, newer, more succulent arose, they could swim, but usually they nurse 5-7 weeks growth. After eating, the before venturing from the nest. beavers gnaw the trees Young remain with their parents up to two years, when into pieces which are they mature sexually. Then they leave on their own, or then used in building the adults drive them off. Two-year-olds usually travel dams or lodges. downstream to look for their own territories, although Small trees are occasionally they strike out across dry land. Beavers eaten more com- have been found miles from water. pletely than Other animals, particularly dogs but oc- larger, woodier casionally bobcats and bears, may ones. kill some individuals — especially Beavers usu- young ones away from the water ally cut trees — but on the whole, beavers within 200 feet of have little to fear from the water's edge; predators. Some are apparently they struck by cars, and a few feel safest within die when hit by trees this zone, and the they felled. Beavers trees don't need live up to 15 years in to be dragged far. captivity; the esti- Beavers cannot mated lifespan in the cut trees and wild is 10-12 years. make them fall in a certain direc- Population tion. They some- times dig canals (1-4 By the beginning of feet wide and up to two feet the twentieth century, deep) from the pond inland to there were few if any float logs back to the dam. beavers in the Keystone Beavers build dams on streams and State. In 1903, the state creeks. This building behavior appears to be instinctive legislature passed a law protecting the species; in 1917, rather than learned. Dams are made of wood cuttings the Game Commission released a pair of Wisconsin bea- packed together with mud and rocks; while a dam may vers in a remote Cameron County valley. Over the next hold back a sizeable pond, it also allows most of the stream decade, the pair and its offspring reproduced and pros- flow to seep through. A dam backs up a barrier of water pered. Beavers from this original stock — supplemented around the beaver's home lodge, much like a moat around with animals bought from Canadian agencies — were a castle. live-trapped and released on refuges throughout the Dams require periodic maintenance, especially after state. By 1934, the population was large and stable heavy rains and during snow melt. Beavers may heighten enough to allow a trapping season. That year more than the dam to raise the water level so they can reach more 6,000 were harvested. Today, beavers are found through- food without having to leave the water; or they may build out Pennsylvania in suitable habitat. additional dams upstream for the same reason. We have had mild winters and good trapping condi- For shelter and rearing young, beavers construct tions since the winter of 1995-96. Over the past six sea- lodges. These are dome-shaped islands of sticks and logs sons, we've harvested an average of 9,811 beavers per plastered with mud. A lodge's interior compartment (the year. During the prior six years, we had an average of den) may be up to five feet high, with a small air hole at 5,244 beavers harvested per year — nearly half the re- the top. The mud freezes in winter, making the lodge
10 cent harvests. of trees; this prevents oxygen from reaching the roots and Beavers can and do become troublesome for some kills the trees within a few years. These "snags" provide people. Water backed up by their dams floods pastures, homes for many cavity-nesting birds. Ponds vary in size crop fields and roads, disrupts public water supplies and from a few to many acres. They provide habitat for ducks, kills trees. They also cut down geese, shorebirds, fish, reptiles and am- phibians. Otters, raccoons, mink, valuable shade trees and ex- herons, ospreys, hawks, owls and cavate unwanted chan- other predators are attracted by nels. Trapping has the rich variety of life and food. proven to be an ac- After the beavers exhaust ceptable and eco- the supply of winter food in nomical method of controlling the area — this may take 10 or more their numbers. years — they move on. Their dam usu- Habitat ally lasts several years longer, accu- Beavers prefer mulating silt, streams and creeks leaves and other narrow enough to organic material. be dammed. They Finally during the also live along riv- spring thaw, or af- ers, on timbered ter a long, hard marshland and rain, the dam gives around forest- way. Most of the edged lakes. They pond water drains prefer remote ar- off, leaving an open eas, but will live area. Grass grows in near man if other the rich soil; later, sites aren't avail- berry bushes and able. shrubs. Insects and Beavers pros- small rodents per in maple, aspen thrive in the new and willow envi- habitat. Deer, bear, ronments. Studies grouse, turkeys, have indicated that songbirds and insec- each year an adult bea- tivorous birds come ver cuts up to 300 trees to these beaver mead- (most having diameters ows, which provide edge less than three inches); and that un- and openings in the forest. der average conditions, one acre of aspen supports a five- The stream continues to flow through the meadow, amid or six-member colony for 1 to 2½ years. many standing dead trees. Aspens and willows send up The dam building of beavers affects many other wild- shoots. In time, another beaver colony may find this val- life species. After a dam is built, a portion of a wooded ley to be good habitat. valley is changed to an open pond. Water covers the bases Wildlife Notes are available from the Pennsylvania Game Commission Bureau of Information and Education Dept. MS, 2001 Elmerton Avenue Harrisburg, PA 17110-9797 www.pgc.state.pa.us An Equal Opportunity Employer
11 Wildlife Notes Allegheny Woodrat Northern Cardinal, Grosbeaks, Indigo Bunting Bats and Dickcissel Beaver Opossum Black Bear Otter Blackbirds, Orioles, Cowbird and Starling Owls Blue Jay Porcupine Bobcat Puddle Ducks Bobwhite Quail Raccoon Canada Goose Rails, Moorhen and Coot Chickadees, Nuthatches, Titmouse and Brown Raptors Creeper Ring-necked Pheasant Chimney Swift, Purple Martin and Swallows Ruby-throated Hummingbird Chipmunk Ruffed Grouse Common Nighthawk and Whip-Poor-Will Shrews Cottontail Rabbit Snowshoe Hare Coyote Sparrows and Towhee Crows and Ravens Squirrels Diving Ducks Striped Skunk Doves Tanagers Eagles and Ospreys Thrushes Elk Vireos Finches and House Sparrow Vultures Fisher Weasels Flycatchers White-tailed Deer Foxes (Red & Gray) Wild Turkey Gray Catbird, Northern Mockingbird and Woodchuck Brown Thrasher Woodcock Herons Wood Duck Kingfisher Woodpecker Mallard Wood Warblers Mice and Voles Wrens Minks & Muskrats
12 Blackbirds, Blackbirds, Blackbirds, Blackbirds, Blackbirds, Wildlife Note — 44 Orioles, Cowbird Orioles, Cowbird Orioles, Cowbird Orioles, Cowbird Orioles, Cowbird LDR0103 and Starling and Starling and Starling and Starling and Starling by Chuck Fergus Except for the European starling, the birds described the nape of the neck; females look like large sparrows. in this Wildlife Note belong to Subfamily Icterinae, the Bobolinks feed on beetles, grasshoppers, caterpillars, ants blackbirds, a group found only in the Americas. (The and other insects, millipedes, spiders, seeds of weeds and introduced starling is covered here because starlings of- grasses, and grain. They nest on the ground in moist mead- ten join feeding flocks containing several kinds of black- ows and fields of hay, clover, alfalfa or weeds. The adults birds.) In the Northeast, blackbirds live mainly in open land away from the hidden nest and walk to it. Most areas such as marshes, fields and woods edges. Some clutches contain five or six eggs. In Pennsylvania bobo- blackbirds are drab, while others are brightly colored. links nest most successfully in the northwest and north- Most species are social, living in flocks outside of the east on farmland at high elevations where cool spring nesting season. and early-summer temperatures retard hay growth and Blackbirds eat mainly insects in summer and seeds in delay cutting until after broods have fledged. Bobolinks winter. Orioles prefer berries to seeds; grackles eat a range start their southward migration in August and Septem- of foods including the eggs and nestlings of other birds. ber; en route, flocks may damage Southern rice fields. Many blackbirds employ a feeding technique called "ma- Most cross the Caribbean and winter in South America. rina." This is when an individual sticks its bill into a crev- ice or vegetation or beneath a rock or a stick, then sud- Red-Winged Blackbird (Agelaius phoeniceus) — Many denly opens its mandibles to push aside or pry away a ornithologists believe the red-winged blackbird is the most screening object to expose an insect, spider, seed or some populous bird species in North America. Redwings breed other edible item. Blackbirds exhibit a range of nesting across the continent and as far south as Costa Rica and the habits: Some species build their nests on the ground, Caribbean Islands. Adults are seven to nine inches long. while others build them in The jet black male has on each shoulder a vivid red patch, marsh vegetation or trees, or epaulet, bordered below by a stripe of yellow; females and the and juveniles lack the epaulets and are drab brown with brown-headed darker streaks. The male's song is a bubbling ook-a-leee , and cowbird does both sexes sound a harsh check as an alarm note. not build a Redwings arrive on the breeding grounds in late Febru- nest at all, ary and early March, with males preceding females by a but lays its week or two. They inhabit cattail marshes, swamps, wet eggs in other meadows, pastures and hayfields; individuals may tempo- birds' nests. rarily leave their home territories to feed in nearby fields. Bobolink In summer, redwings eat dragonflies, mayflies, caddisflies, (Dolichonyx midges, mosquitoes, caterpillars, beetles, grasshoppers, ci- oryzivorus) — cadas and many other insects. In fall and winter they turn Bobolinks to seeds, which make up about three-quarters of the annual breed across diet. They consume seeds of grasses and weeds, and grains southern dropped by farm machinery. Flocks of red-winged black- Canada and birds may damage corn, wheat, oats, barley, rice and sun- the northern flower crops. United States. Adults usually breed within 30 miles of where they Males are black, were hatched. In spring the males perch prominently, with white on the displaying their epaulets and calling to attract females back and yellow on and intimidate other males. (When venturing across or Red-Winged Blackbird
13 Common Grackle into other territories to feed, males hide their epaulets by covering the red with adjoining black feathers, mak- ing it less likely that they'll be attacked by resident males.) 1 Each male guards a breeding territory of / to ¼ of an 8 acre; within this area, one to several females will nest. A male may mate with several females, and a female may mate with more than one male. Females first breed when they're one year old. Yearling males do not often breed, although they continually try to take over older males' territories; sometimes yearlings displace reigning males, sissippi Valley. In times past, but more often they fail and must wander about during redwings were more limited summer or until a territory opens up after its owner is to wetland areas; the popula- killed. tion increased after the species Redwings nest in loose colonies. They aggressively at- began branching out and nesting in agricultural areas. tack crows and hawks to drive them out of the area. Males About 40 percent of adult redwings perish each year. The do not help with nest building. Females attach their open- average life span is two to four years. cup nests to cattail stalks or other marsh vegetation or place them in low trees near or over the water; in hayfields and Eastern Meadowlark — Both males (Sturnella magna) upland sites, females hide their nests in grass, weeds or and females have a brown-streaked back and a bright yel- shrubs. A female lays three or four pale bluish eggs, blotched low breast with a prominent black V; the outer tailfeathers with browns and purples. Incubation takes 10 days to two are white. Meadowlarks live in pastures, hayfields, fallow weeks. Both parents feed insects to the hatchlings, and the fields, and stripmines that have been replanted to grass. In young leave the nest after about two weeks. In the North- summer they eat grasshoppers, crickets, beetles, ants, cat- east, most redwing females raise one brood per year, erpillars and many other insects; they also eat seeds and renesting if a predator destroys an early clutch. Nest preda- waste grains. Males arrive in the spring two to four weeks tors include crows, marsh wrens, raccoons and minks. before the females and stake out territories, which average In winter, red-winged blackbirds often feed alongside seven acres. The males perch on phone poles, trees and grackles, cowbirds, starlings and robins. Redwings usually fenceposts, singing their sweet, slurred, whistling song. Sixty fly between food sources in long, strung-out flocks. At to 80 percent of males have two or three mates. The female night they roost communally, males grouped separately builds a ground nest in grass or weeds 10 to 20 inches high; from females. Most redwings winter in the southeastern the nest, usually in a slight depression, is made of dry grasses United States, with huge concentrations in the lower Mis- with a woven dome-shaped roof and a side entry. Females lay eggs from late May through June. Early mow- ing of hayfields destroys many nests. The three to five eggs are white, heavily blotched with brown. The female incu- bates her clutch for about two weeks. After the young hatch, both parents feed them insects. Fledglings leave the nest after 10 to 12 days and are fed by their parents for another two to four weeks. Some females raise two broods over the summer. In August, meadowlarks abandon their breeding territories and forage in small flocks. In September and October most shift southward, migrating at night and feed- ing during the day. Some meadowlarks winter in eastern and western Pennsylvania, although most go farther south. The population has declined in the Northeast over the past 40 years as development has wiped out agricultural land and formerly farmed areas have grown up into brush and woods. (Quiscalus quiscula) — Grackles are Common Grackle sleek black birds with iridescent purple, green and bronze highlights in their plumage. Adults are about one foot in length and have long wedge-shape tails. Grackles live in suburbs, towns, farming areas and streamside groves. They Eastern Meadowlark
14 Brown-Headed Cowbird forage mainly on the ground and eat insects (beetles, grubs, grasshoppers, caterpillars and many others), millipedes, spi- ders, earthworms, crayfish, minnows, frogs, the eggs and young of other birds, and even small rodents. In spring, males display in front of females by raising their bills, fluffing out their feathers, spreading their tails, and singing a loud, as- cending reedeleek . Unlike most other songbirds, grackles remain social throughout the year. Most nest in colonies of 10 to 30 pairs, usually in evergreen trees, where mated pairs defend only a small area right around their nest. Grackles nest from April into July. The female builds a cup-shape nest out of grasses and mud. The typical clutch has four or five eggs. Only the female incubates, and the eggs hatch after 12 to 14 days. Both parents feed the young, which fledge after 16 to 20 the young cowbirds as their own. Ornithologists believe days. In the fall, grackles roost in large flocks, along with that cowbirds did not live in forested Pennsylvania be- starlings, red-winged blackbirds and cowbirds. Most grack- fore European settlement, a theory bolstered by the fact les winter to the south of us, but some stay on here. that few of our native songbirds have evolved defense behaviors against its parasitism. Today, cowbirds are com- Brown-Headed Cowbird — The (Molothrus ater) mon breeders statewide, mainly in farmland and in areas brown-headed cowbird is a bird of farms, fields and woods where development has fragmented the forest, giving edges. Males have black bodies and brown heads; females them access to the nests of woodland birds. Cowbirds have are brownish gray. Seeds of grasses and weeds, plus waste been reported to parasitize more than 220 different spe- grains, make up about half of the birds' diet in summer and cies. In the Northeast, cowbirds particularly plague war- more than 90 percent in winter. Cowbirds also eat insects, blers, vireos, flycatchers, finches, thrushes and sparrows. particularly grasshoppers, beetles and caterpillars. In the past, A female cowbird will sneak in to a nest that is tempo- cowbirds followed bison herds on the Great Plains, where rarily unoccupied, quickly lay an egg, and fly off, sometimes they were known as "buffalo birds." after removing or eating one of the host's eggs. Cowbird eggs In spring, the male cowbird displays for females by fluff- are whitish, with brown and gray spots. Young cowbirds, ing up his body feathers, spreading his wings and tail, and hatched and fed by the host parents, grow rapidly; they glug-glug-gleee singing a bubbly . The species builds no nest. monopolize food and may even crowd the other young out The cowbird is a brood parasite: The female lays eggs in the of the nest. Juvenile cowbirds fledge 10 to 12 days after hatch- nests of other birds who, guided by their instincts, raise ing. In one study, a successfully raised cowbird caused a re- duction in the brood of a host pair by only one fledgling. Other ornithologists cite cowbird predation as a major fac- tor — along with habitat loss — in declines of many spe- cies, including the wood thrush. A female cowbird may lay up to 40 eggs in one season; of these, two or three will yield young that ultimately mature to adulthood. Cowbirds mi- grate in large flocks in spring and fall. They winter mainly in the southern states and in Central America. Often they share huge winter roosts with starlings and other blackbirds. Orchard Oriole — The adult male is (Icterus spurius) chestnut and black, and the female is olive and yellow. This robin-size oriole inhabits open areas, including parks, old orchards, and shade groves, with scattered large trees; it avoids deep woods. In Pennsylvania, the species breeds most commonly across the southern part of the state. Orchard orioles feed on insects, berries, nectar and flowers. Pairs are thought to be monogamous. The female builds a hanging basketlike nest among dense leaves in a tree, usually 10 to 20 feet above ground. The 3 to 7 eggs are incubated for 12 to 15 days. Both parents feed the young, which leave Baltimore Oriole
15 the nest about two weeks after hatching. Brown-headed cowbirds often parasitize orchard oriole nests. Long-dis- tance migrants, orchard orioles winter in Mexico and Central America. Baltimore Oriole (Icterus galbula) — Also called the northern oriole, the male of this species has a brilliant or- ange body and a black head (black and orange were the he- raldic colors of Lord Baltimore, an English colonist and founder of present-day Maryland). The female is yellow-orange. Baltimore orioles breed throughout eastern North America in open woods, residential areas, parks, European fencerows and tall trees along streams (often sycamores or Starling willows; formerly elms were a favorite before disease killed most American elms). Adults feed on insects, particularly caterpillars; spiders; snails; berries, including mulberries, ser- viceberries, and blackberries; cultivated fruits; and flowers. Baltimore orioles visit feeding stations for sugar water and pieces of fruit. The species is best known for its sacklike hanging nest, intricately woven by the female out of plant fibers, pieces of string, grapevine bark and grasses. A central chamber is lined with hair, fine grasses and cottony plant matter. Nests are usually hung at the ends of pliant branches, probably to de- ter predators, including snakes, blue jays and crows. Females ices in trees and buildings, and bird houses. In April, males lay three to six eggs that hatch after 12 to 14 days. Both perch outside the cavities; when they see other starlings, parents feed the nestlings, which leave the nest after two they sing and windmill their wings to attract a mate. The weeks. Flocks depart from the breeding range quite early, in male's song includes shrill squeals, squawks and imitations July and August. The species winters in southern Mexico, of other birds' songs. The female fills the nest cavity with Central America and northern South America, where the grasses, weed stems, twigs, old cloth and dry leaves, then birds feed on insects and nectar. lines a central cup with fine grasses and feathers. She lays four to six eggs, which are an unmarked pale bluish green. — From 100 birds European Starling (Sturnus vulgaris) Both parents incubate the eggs, and they hatch after about released in the 1890s in New York City's Central Park have 12 days. The nestlings are fed by both parents and leave descended more than 200 million starlings populating North the nest three weeks after hatching. By now their drop- America today. Starlings are chunky birds with short tails pings have so fouled the cavity that the adults go in search and long straight bills; airborne, they show a distinctly tri- of another nest hole in which to rear a second brood: Of- angular shape. The plumage is black with iridescent high- ten they drive native birds from their nests, including lights. Starlings are adaptable, hardy and wary. They inhabit woodpeckers, nuthatches, great crested flycatchers, tree farmland, suburbs, cities and woods edges, and are least nu- swallows, house wrens and bluebirds. Harassment by star- merous in or are absent from marshes and extensive forests. lings may have caused recent declines in populations of Starlings eat almost equal amounts of animal and plant food, the northern flicker and red-headed woodpecker. including beetles, grasshoppers, ants, flies, caterpillars (gypsy Starlings feed in flocks and roost together at night. In moth and tent caterpillars are frequent prey), earthworms, late summer and fall, their roosts may contain thousands of grains, cherries and mulberries. When foraging on lawns in birds. Some individuals shift southward for the winter, while winter, starlings are usually gaping, probing their bills into others remain in the Northeast; many roost in cities, where the soil and prying apart grass roots to uncover beetle buildings give off heat, and then fly out into the surround- larvae. ing agricultural land to feed during the day. Of the starlings Starlings begin defending nest cavities in late winter, that are alive in January, about half die in the coming year, pre-empting them before native cavity-nesters start claim- with one third of the deaths happening in January and Feb- ing territories. Starlings nest in woodpecker holes, crev- ruary. The average adult's life span is one and a half years. Wildlife Notes are available from the Pennsylvania Game Commission Bureau of Information and Education Dept. MS, 2001 Elmerton Avenue Harrisburg, PA 17110-9797 www.pgc.state.pa.us An Equal Opportunity Employer
16 Wildlife Note — 59 LDR0103 Blue Jay by Chuck Fergus (Cyanocitta cristata ) belongs to Family The blue jay ter; ones they don't retrieve help forests to regenerate, Corvidae, the Corvids, which also includes crows, ravens, particularly on cut-over and burned lands. Confronted and magpies in North America, and jackdaws, choughs with abundant nuts and seeds, a jay may fill its expand- and rooks in the Old World. Because Corvids have the able throat; later, it will disgorge the food and cache or largest cerebrums, relative to body size, of all birds, sci- eat it. To open an acorn, the bird grips the nut in one entists believe them to be the smartest. Corvids are so- foot and hammers the shell apart with its bill. cial birds, with many species living in flocks when not jaay Blue jays are quite vocal. They sound a raucous nesting. The bold, colorful blue jay breeds from south- to attract other jays and as an alarm call. A bell-like ern Canada south to Florida and west to the Rocky Moun- call, wheedelee is given during courtship, as is a toolool tains. sometimes referred to as the "squeaky hinge" call. Blue jays often mimic the kee-yer calls of hawks. Biology Blue jays have an interesting social courtship. In early spring, from 3 to 10 males (thought to be yearling birds) The blue jay is 11 to 12 inches in length (larger than a shadow one female, bobbing their bodies up and down robin) and has a blue back marked with black and white; and sounding toolool calls. Aggressive displaying appar- its underparts are off-white, and it has a prominent blue ently scares off the competitors one by one until a single crest on its head. The sturdy beak is straight and sharp, male is left as the female's mate. Ornithologists believe well suited for a variety of tasks including hammering, that older jays, ones that have bred in the past, pair up probing, seizing and carrying. earlier and do not participate in courtship flocks. Once Blue jays live in wooded and partly wooded areas, in- paired, birds move about quietly, with the female giving cluding extensive forests, farm woodlots, suburbs and calls to the male when he brings her food. The kueu kueu towns. About three-quarters of their diet is vegetable female may make several preliminary or "dummy" nests, matter: acorns, beechnuts, various seeds (including sun- using twigs brought by the male. Later the female, with flower seeds from feeding stations), corn, grain, fruits and help from her mate, assembles the breeding nest, often berries. The remaining 25 percent includes insects: ants, in a dense conifer or shrub, 5 to 50 feet above the ground. caterpillars, beetles, grasshoppers and others, along with The nest is seven to eight inches across, built of twigs, spiders, snails, frogs, small rodents, carrion and eggs and bark, mosses and leaves, with a 4-inch central cup lined nestlings of other birds. with rootlets. In the spring, blue jays eat caterpillars of the gypsy In May or June the female lays three to six eggs, pale moth and the tent moth, major forest pests. In autumn, olive or buff, spotted with brown or gray. Both sexes in- jays cache many acorns under the leaf duff in forest clear- cubate. Blue jays are silent and furtive around the nest; ings and meadows. They retrieve some of the nuts in win- one year a pair nested in a white oak next to our house,
17 and I hardly knew they were there once egg-laying and Canada shift southward in September and October, and juveniles from the northern United States also drift to incubating commenced. Blue jays strongly defend their nest against intruders, calling loudly and diving at and the south. In some years — perhaps when wild nuts, or mobbing hawks, owls, crows, squirrels and ground preda- mast, are scarce — blue jays move in large numbers; ac- tors. Yet they will allow other jays to land quite near the cipiters, particularly sharp-shinned and Cooper's hawks, nest. The eggs hatch after 17 to 18 days. Both parents accompany the flocks, picking off unwary members. Blue jays are common migrants in Pennsylvania in April and feed the young, bringing them insects, other invertebrates and carrion. Adult blue jays often raid early May. The longevity record for the species is 16 years. Among adults, the annual survival rate is esti- the nests of smaller birds, including vireos, warblers and sparrows, eat- mated at 55 percent. ing eggs and nestlings. Biologists believe that forest fragmenta- Habitat tion is giving jays greater access to the nests of Blue jays avoid strictly coniferous forests. woodland birds. They thrive in areas with plentiful nut-bear- The young ing oak and beech trees. Although prima- leave the nest after rily forest birds, blue jays have adapted 17 to 21 days. The to living in cities, where they nest in family stays to- parks and along tree-lined streets, and gether for another feed at bird feeders. month or two, with ing for the fledglings clamor- Population food and their parents obliging them, even when the juveniles The blue jay popula- are almost adult-size. In the tion in Pennsylvania and North, blue jays raise one brood the Northeast is healthy. per summer; jays in the South may rear The birds nest over vir- two. When the adults molt in July and August, their new tually all of the state, and were found to be among the plumage comes in a lustrous, beautiful blue. (In fact, the top 10 most widely distributed species when the Penn- blue of the birds' plumage is not caused by pigmenta- sylvania Breeding Bird Atlas was being conducted in the tion, but by structure: the feathers do not absorb the blue late 1980s. On a continental scale, the species is expand- part of the light spectrum and, instead, cause it to scat- ing northwest into Canada. Biologists estimate two or ter, giving an appearance of blue. three breeding pairs of blue jays per 100 acres of suit- In late summer and early fall, family groups merge into able habitat. Blue jays migrate in spring and fall, and more larger foraging flocks. As the weather grows colder these than 5,000 a day can be seen flying over the Lake Erie groups fragment again into smaller bands. Birds from Shore during the first two weeks of May. Wildlife Notes are available from the Pennsylvania Game Commission Bureau of Information and Education Dept. MS, 2001 Elmerton Avenue Harrisburg, PA 17110-9797 www.pgc.state.pa.us An Equal Opportunity Employer
18 Wildlife Note — 3 LDR0103 Bobcat by Chuck Fergus Tawny, tireless, smooth-moving and shy, bobcats are cats are colorblind and see only in shades of gray. truly beautiful animals. Few persons ever actually see a Small animals — mice, rats, shrews, squirrels, chip- bobcat; spotting one in the wild is a tremendous thrill. munks, birds, rabbits and hares — form the nucleus of Despite the bobcat's elusiveness, many Pennsylvanians the bobcat's diet. But like most other predators, cats are are intrigued by this predator. opportunists, and porcupine, mink, muskrat, skunk, fish, frog, insect and fox remains have also been found in their Biology stomachs. Occasionally bobcats take sick, weak or crippled deer, The bobcat — also known as the bay lynx, wildcat, but predation by bobcats has little or no effect on the red lynx and swamp tiger — is our state's only feline preda- size of Pennsylvania's deer herd. After feeding on a deer, tor. Its scientific name is , and it is closely re- Lynx rufus a bobcat may cover the rest of the carcass with leaves. lated to the Canada lynx, which is not found in Pennsyl- Bobcats also feed on whitetails which have starved dur- vania. ing winter or died of other causes. Bobcats are efficient, wary predators equipped with Breeding takes place from late February to early sharp senses of sight, smell and hearing. They have four March. Male bobcats don't become sexually mature un- large canine teeth to pierce deeply into prey; behind the til two years old. Females can breed in their first year, canines are sharp cutting teeth. Five retractable, hooked but often do not. During estrus, a male may travel up to claws on each front foot and four on the rear add to the 20 miles in a single night searching for a receptive fe- armament. male. Radio telemetry research indicates that the male Though it's a fierce fighter, a bobcat isn't a large ani- leaves the female after mating and plays no part in rear- mal. A mature bobcat averages 36 inches in length, in- ing young. cluding a stubby, 6-inch tail. This bobbed tail gives the Kittens are born following a 50- to 60-day gestation bobcat its name. Pennsylvania bobcats weigh 15 to 20 period. Litters range from one to four young, with about pounds, with large individuals as heavy as 35 pounds. two the average. Females guard their litters carefully, as Eight bobcat subspecies are found in the continental an adult male bobcat may try to kill and eat the young. United States, with slightly varying pelt coloration and Owls and perhaps foxes may take kittens. A mature bob- sizes. The bobcats in our state have gray-brown fur with cat has few enemies dark spots and bars, which are especially noticeable on other than man. the legs. Lips, chin, the underside of the neck and the Bobcats give belly are white. A ruff of fur extends out and downward birth in dens — from the ears. rock crevices, The bobcat's rangy, muscular back legs are longer than caves and hollow its front legs. This gives the animal a high-tailed, bob- logs insulated bing gait when it runs. The bobcat is a strong swimmer with dry leaves — although it usually jumps creeks or fords them on fallen and mosses. logs — and an excellent climber. Though fully Bobcats are mainly nocturnal, but they sometimes furred, kittens venture out in the daytime. They have large eyes, well- are blind and adapted to see in the dark; bobcat pupils are slit-shaped helpless at birth; rather than round and can open wide to admit light. Two their eyes open other eye adaptations that help night vision are abun- after eight or nine dant light-sensitive rods and a reflecting layer that makes days and they are an object stand out sharply from its background. Bob- weaned within two
19 ous areas. They are well established in northcentral and months. Kittens stay with their mothers for several more northeastern counties. Over the past 20 years, bobcats months, learning to hunt and kill prey, and reach 60 per- have increased in number statewide and have been con- cent of their adult weight by winter. tinually expanding their range. Most wild animals are bothered by parasites, and bob- cats are no exception. Fleas, mites and stomach and in- Population testinal worms afflict bobcats. There have been few re- ports of rabid bobcats. Population is in many ways a factor of habitat — poor Some individuals live up to 14 years in the wild. Re- habitat means low population. As Pennsylvania's second- searchers aged captured animals by examining their teeth; growth forests matured and the number of prey animals each year the outer cementum layer of a bobcat's canine decreased, the bobcat population fell, too. Fewer and teeth lays down a growth ring, much like a tree does, thus fewer bobcats were spotted, and even tracks became hard making age determination possible. Bobcats in captivity to find. In 1970, the Game Law was changed to give the usually live longer than those in the wild; one 30-pound bobcat complete protection, and bobcat numbers sub- captive male reached age 25. Research has shown a high sequently increased. mortality rate among bobcats during their first and sec- Tough, resilient predators, bobcats are, nevertheless, ond winters, before the young cats have completely mas- affected by development of once-remote land, more and tered hunting skills. more houses, woods roads that open previously un- During bad winter weather, a bobcat may shelter un- touched areas to noise, and disturbances from ATVs and der overhanging rocks or in rock crevices. As soon as other vehicles. These intrusions, coupled with habitat the storm subsides, though, the bobcat will be out hunt- change are threats to the bobcat's well-being in the more ing. If you can find its tracks in the snow, follow a bobcat developed areas of the state. on the prowl. Tracks will lead up and down mountains, Beginning in the 1980s, the Game Commission began cross streams (often on logs) and continue for miles. A various field research projects to better understand the hunting bobcat trots to a vantage point — a rock forma- factors affecting bobcat density and distribution tion, steep hillside, low-leaning tree — and surveys its throughout the state. Based on these studies and related surroundings. Rock crevices, stumps, brush piles and surveys, in 2000 Pennsylvania's bobcat population was thickets will be checked by a bobcat in search of a meal. estimated to be approximately 3,500, and a hunting and Individual bobcats have a definite territory, which is trapping season, very limited, was once again offered. marked with feces, urine and scrape marks, and which may overlap the territories of other bobcats. Size of the territory depends on availability of food. In areas where food is abundant, the range may be as small as five miles in diameter. In the Western states, a low density of prey forces bobcats to range wider. Habitat In Pennsylvania, bobcats usually inhabit mountains, deep forests, swamps and, occasionally, agricultural ar- eas. Obviously, bobcats will live in areas where they can find ample shelter and food. Bobcats seem to prosper in remote areas near clearcuts. Studies have shown that the number of small mammals — rats, mice, shrews, etc. — increases following clearcutting (due to better food and cover conditions), and apparently cats respond to this increased prey supply. Oak leaf roller and gypsy moth caterpillars, insect pests which kill timber, may also in- directly increase small mammal populations by opening up the forest canopy and thus stimulating low, brushy growth. A century ago, much of Pennsylvania was brushy, sec- ond-growth forest with an accompanying large popula- tion of grouse, rabbits, hares and small rodents. This ter- rific animal food supply and abundant uninhabited land Wildlife Notes are available from the allowed the bobcat to prosper. But when the forest ma- Pennsylvania Game Commission tured, when saplings and sprouts grew into mature tim- Bureau of Information and Education ber, when brush, thick laurel and blackberry tangles were Dept. MS, 2001 Elmerton Avenue replaced by a bare forest floor — and when man's cities Harrisburg, PA 17110-9797 and towns continued to expand — the amount of habi- www.pgc.state.pa.us tat suitable for bobcats shrank. Bobcats are generally found in the state's mountain- An Equal Opportunity Employer
20 Wildlife Note — 20 LDR0103 Canada Goose by Chuck Fergus The lines and vees of geese come south from the tun- Branta Our resident geese are giant Canada geese ( dra. The birds pass over Pennsylvania each fall, some trav- canadensis maxima ). Resident geese are largely non-mi- eling by day others winging across night skies. Their flight gratory; they nest and winter here. The growth of this can be high — so high that their incessant calls do not population has been phenomenal. Prior to 1935, no reach earth — or low enough that the honking carries Canada geese nested anywhere in Pennsylvania. But to- clear as church bells on a frosty morning. The lines and day they can be found nesting in every county. vees may be long and undulating, or tight, strong and Geese are large, plump birds with long necks, short symmetrical. They are following long established migra- wings, a broad, round-tipped bill and short legs. Their tory highways to their wintering grounds — an ancient legs are set farther forward than those of ducks or swans; rite of autumn that will be reversed in spring. this adaptation permits them to walk and graze on dry land. The feet are webbed between the three front toes. Biology race average 36 Adult males, or ganders, of the interior inches in length and weigh approximately nine pounds. The Canada goose ( Branta canadensis ) is a member of Females and immatures are a bit smaller and lighter. Order Anseriformes, Family Anatidae, a large group com- Both sexes of Canada geese look alike. The bill, head, prising all North American waterfowl. Waterfowl are fur- neck, legs, feet and tail are black. There is a broad white ther divided into seven subfamilies, one each for swans cheek-and-chin patch; the upper body is gray-brown. and geese, and five for ducks. Flanks and underwings are a lighter gray, as are the breast Canada geese belong to subfamily Anserinae. They and belly, which are also faintly barred. Geese have large are closely related to emperor, snow, blue, Ross's and amounts of down — fluffy feathers close to the body white-fronted geese, and brants. Canada geese occur in which create insulating dead air space — to keep them 11 different races or subspecies, which differ in size and warm in cold weather. color. Smallest is the cackling Canada goose (weight, Grazing birds, geese feed on wild and cultivated plants. about 3 pounds); largest, the giant Canada goose (11 to They eat rhizomes, roots, shoots, stems, blades and seeds. 13 pounds). As a group, Canada geese are of- Foods: widgeon grass, pondweed, eelgrass, ten referred to as "honkers." spike rush, American bulrush, cordgrass, Three distinct glasswort, algae, grass, clover, wheat, Canada goose subspe- millet, corn, barley and rye. They cies occur in Pennsyl- can damage cultivated crops, vania. Two are mi- particularly young shoots of grants that breed in fall-planted wheat. Animal Canada; the third matter isn't a major part breeds here. The mi- of their diet, although grants comprise geese from they sometimes eat in- the Southern James Bay popula- sects, crustaceans and ), Branta canadensis interior tion ( snails. which fly over westernmost Pennsyl- When feeding in vania, and the Atlantic population shallow water, geese tip ( Branta canadensis canadensis ), which their bodies, dip their migrate over eastern Pennsylvania. heads under and pull up
21 geese are gregarious from late summer through winter, vegetation. On land, they feed in groups — and at least nesting adults are more likely to be found by themselves. one member of the party always has its head up, looking Canada geese are highly successful in raising broods, for danger. Geese generally move in patterns to feed. Each but those nesting in northern Canada are highly suscep- day about dawn, they leave the water — river, pond, lake, tible to weather conditions. Late spring snow storms and impoundment, or whatever — fly to feeding areas, and cold weather can severely impact nesting and brood-rais- feed for two or three hours. Then they return to the wa- ing. Flooding and predation can also cause nest failure. ter, rest and fly out to feed again in the evening. On such Raccoons, opossums and skunks destroy eggs; foxes and forays they fly from a few hundred yards to over 20 miles, owls prey on goslings. depending on availability of food. Geese are intelligent and wary. Their vision is sharp Population and their hearing keen, and these senses are multiplied when the birds are in flocks. In regions where they are The range of the Canada goose blankets the United hunted, they quickly learn locations and boundaries of refuges where they're protected. States and most of Canada. There probably are more geese on the continent today than when the Pilgrims A honker usually runs along the surface of the water or ground to gain lift for takeoff, though when landed; like some other wildlife species — blackbirds, crows, woodchucks, and white-tailed deer — honkers surprised can jump into flight as puddle ducks have benefitted from increased agricultural produc- do. Once aloft, its flight may appear slow and tion. Geese feed abundantly on grains and cereal labored — perhaps because of the bird's crops on their migration and wintering grounds. slow, deep wingbeats and large size — but Geese on the Atlantic Flyway now rely more on actually it can reach 45 to 60 miles per crops than on aquatic plants. hour. In flight, geese sound their distinc- tive "honking" calls; when feeding, they A century ago, the Canada goose population had dropped dangerously because of unre- make a gabbling sound, and when angry, stricted market hunting on the they hiss. species' wintering grounds and In spring, honkers are among the first waterfowl to migration routes. Fortunately, strict law enforcement, wild- breed. Unmated life management practices males fight for fe- males; the males ap- and increased farming proach each other have reversed this trend. The resulting in- with necks lowered crease in the goose and extended, hissing loudly, pecking and population rivals the flailing with their powerful comebacks of the wild wings. Individuals of both turkey and white-tailed deer. sexes usually mate for the first time in their second or third year. Migratory birds, geese The pair stays together as long as both fall under the jurisdiction are alive and healthy; if either dies, the other of the federal government's U.S. Fish & Wildlife Service. This agency cooperatively usually looks for a new mate. Geese nest in a wide variety of habitats. They like sites manages all waterfowl with the states and Canadian prov- inces. This work includes monitoring populations and that afford an open view. These include islands in rivers and lakes, the tops of muskrat houses in large marshes, habitat, conducting research and setting annual seasons and bag limits. rocky cliffs, abandoned osprey and heron nests, artificial nesting structures and grassy fields near water. The fe- male usually selects the site and builds the nest. Nests Habitat are typically ground depressions lined with sticks, cat- tails, reeds and grasses. A central cup may be lined with Landowners interested in attracting migrating geese down, which the female plucks from her breast. Outside can leave portions of crops unharvested. Good foods are dimensions of nests vary from 17 to 48 inches, with 25 barley, wheat, rye, grasses and corn. In feeding studies, inches the average. Inside diameter of the central cup is fields of corn and small grains attracted most geese. Geese 9 to 11 inches, and the nest may be 3 to 6 inches deep. generally will not land close to fencerows, woodlots, The female lays 4 to 10 eggs (usually 5 or 6). Geese houses or barns. Strips of corn alternating with wide grass nesting for the first time generally lay fewer eggs than fields often will draw flights. Geese are quite mobile — willing and able to fly great older birds. The eggs are creamy white and unmarked at first, either smooth or with a slightly rough texture; as distances to find food and resting areas. Grazing birds, time passes, they become stained. Incubation averages they are generally more land-based than ducks, especially about 28 days. The gander does not sit on the eggs but is when goslings are growing. Breeding habitat is tremendously variable; they do always nearby, guarding and defending the nest and sur- rounding territory. To avoid detection on the nest, a goose well in open fields near water, on islands, rocky cliffs, will crouch, extend her neck, and remain still. Although etc. Artificial nesting structures — tubs secured to trees,
22 old tractor tires placed on islands, or platforms built over tion: during spring, altitudes average a bit lower). Geese water — may attract resident honkers. Geese raise fami- fly high over long distances, lower for short hops. lies in city parks, reservoirs and farm ponds, although the Geese of the Atlantic Flyway winter primarily in Chesa- peake Bay and Delmarva region. Smaller numbers winter vast majority breed in the far north. from as far north as New York and coastal New England Goslings are precocial. Their eyes are open, they are to southeastern Pennsylvania and New Jersey. covered with a fine, brown fuzz, and they're able to walk In spring, honkers retrace their routes to ancestral and swim soon after they hatch. They leave breeding grounds. Migrating flocks are composed of the nest from several to 24 several family units, parents and offspring of the pre- hours after hatching. Both parents stay with vious year, but the yearlings leave their parents the goslings, and the shortly after arrival. Adults usually nest in the female broods them same locale year after year, some even using the nightly for about a same nest foundation. In Pennsylvania, geese are common week, and then less of- spring migrants in late February, March and ten. When young are half- early April, with stragglers into May. In grown, their parents begin to molt. Adults summer, resident flocks breed here: lose their flight feathers and are grounded for strong concentrations exist in Game about three weeks; during this time, the goslings Commission waterfowl areas such as are growing their own flight feathers, so parents and Pymatuning and Middle Creek, as young are able to fly at about the same time. well as other suitable habitat in the As autumn approaches, geese prepare to migrate. state. In fall, honkers are common Family groups gather in small flocks, leave the breeding grounds and fly leisurely to staging areas along the route September-November migrants. If the winter is mild, some stop in the south. Migrating geese travel by day or night, flying un- til tired and then landing to feed and rest. southeastern portion of the state, although most go farther south. Honkers fly in vees or occasionally in single, diagonal Because they're big, strong lines. A trailing goose encounters less air resistance, thus and aggressive, geese are less sub- uses less energy, because of the turbulence set up by the bird flying just ahead. ject to predation than most other water- fowl. Hawks and owls prey on immatures and some adults, Flight altitudes vary with weather conditions, distance and snapping turtles, snakes and land-based predators take to be flown and time of year. In heavy overcast, honkers may fly only a few hundred feet off the ground; under fair goslings which stray from their parents' protection. Dis- skies, they tower up almost a mile. An average derived ease, parasites and accidents also take their toll, and an- from airplane pilots' reports is 2,000 feet, with 64 per- nual mortality ranges form 32 to 52 percent. Geese have cent between 750 and 3,500 feet (this was for fall migra- potential lifespans of 15 to 20 years. Wildlife Notes are available from the Pennsylvania Game Commission Bureau of Information and Education Dept. MS, 2001 Elmerton Avenue Harrisburg, PA 17110-9797 www.pgc.state.pa.us An Equal Opportunity Employer
24 Wildlife Note — 42 Chickadees, LDR0103 Nuthatches, Titmouse and Brown Creeper by Chuck Fergus These woodland birds are mainly year-round residents in (five inches long), spunky bird. Chickadees have short sharp their breeding areas. They become most apparent in fall and bills and strong legs that let them hop about in trees and winter when all four types may occasionally be seen together, cling to branches upside down while feeding. They fly in an along with downy woodpeckers and kinglets, in undulating manner, with rapid wingbeats, rarely going farther mixed-species foraging flocks. In these groupings, the greater than 50 feet at a time. The species ranges across northern number of eyes may improve foraging efficiency and detect North America, living in deciduous and mixed forests, forest potential predators. Our two chickadees and the tufted edges, thickets, swamps, and wooded areas in cities and titmouse belong to Family Paridae, omnivorous feeders that suburbs. Black-capped chickadees are common throughout cache excess seeds in holes or bark crevices, remember the Pennsylvania, except for the state's southwestern and locations, and return later to eat the food. The two southeastern corners, where they're replaced by the similar nuthatches are in Family Sittidae. They glean insect food Carolina chickadee. from the trunks of trees and also eat nuts; their common About two-thirds of a chickadee's diet consists of animal name derives from the way they "hack" nuts apart using their protein: moth and butterfly caterpillars (including early stout pointed bills. Taxonomists place the brown creeper in growth stages of gypsy moths and tent moths), other insects Family Certhiidae, a group that includes only six species, and their eggs and pupae, spiders, snails and other the other five of which inhabit Europe and Asia. invertebrates. In late summer and fall, chickadees eat wild berries and the seeds of ragweed, goldenrod and staghorn Black-Capped Chickadee ( Poecile atricapillus ) — A black sumac. In the fall chickadees begin storing food in bark cap and bib, buffy flanks, and a white belly mark this small crevices, curled leaves, clusters of pine needles, and knotholes. The birds rely on these hoards when other food becomes scarce. Chickadees also eat suet from feeding stations and fat from dead animals. In winter, chickadees live in flocks of six to 10 birds with one dominant pair. Listen for the calls that flock members use to keep chick-a-deedee-dee in contact while foraging around a territory of 20 or more acres. A flock will defend its territory against other chickadee flocks. At night chickadees roost individually in tree cavities or among dense boughs of conifers. A roosting bird tucks its head under a wing to conserve body heat. On cold nights, a chickadee's temperature drops from a normal o o F, causing the bird to enter a F to about 50 108 state of regulated hypothermia, which saves significant amounts of energy. Chickadees lose Black-Capped weight each night as their bodies slowly burn Chickadee fat to stay alive; they must replace those fat stores by feeding during the next day. Chickadees mate for life. In spring, the
25 winter flocks break up as pairs Tufted Titmouse ( Baeolophus bicolor ) — This trim Tufted Titmouse claim nesting bird has gray-and-white plumage, a prominent head crest, territories and black "shoebutton" eyes. The species ranges through ranging from 3 eastern North America into southern New York and New to 10 acres in England. It has extended its range northward over the last size. half-century, perhaps because of climatic warming and Chickadees an increase in bird feeding by humans. In the early l900s nest in May and the tufted titmouse was absent from northern June. The usual Pennsylvania; today it breeds statewide. site is a hole in Titmice eat insects (caterpillars, wasps, bees, sawfly a tree, dug out larvae, beetles and many others, as well as eggs and by both pupae), spiders, snails, seeds, nuts and berries. Like the sexes. Birch chickadee, the titmouse forages by hopping about in tree is a branches, and often hangs upside down while inspecting favorite, the underside of a limb. To open a nut or seed, the bird because holds the object with its feet and pounds with its bill. this tree's Titmice cache many seeds; with sunflower seeds, the birds tough usually remove the shell and hide the kernel within 120 outer bark feet of the feeding station, under loose bark, in cracks or stays intact furrows in bark, on the ground, or wedged into the end of after the inner a broken branch or twig. wood rots and Winter flocks are often made up of parents and their becomes soft enough young of the previous year. Titmice are early breeders: males for chickadees to start giving their Peter Peter territorial song in February. In excavate. Pennsylvania, pairs begin building nests in late March and Chickadees also clear out early April. Titmice are believed not cavities in aspen, alder, willow, to excavate their own nest cavities; and cherry trees, and use instead, they use natural cavities or abandoned woodpecker holes. The abandoned woodpecker holes. cavity is usually 4 to 10 feet above the Breeding territories average 10 ground. The female assembles the nest by acres. The female lays five or six laying down a base of moss, then adding softer eggs, which are white with dark material such as animal fur or plant fiber. House speckles, and incubates them for wrens compete for nest cavities and may destroy two weeks. The young fledge chickadee eggs and broods; raccoons, opossums and about 18 days after hatching. squirrels raid nests. Chickadees will renest if a first Sometimes yearling birds stay attempt fails. Only one brood is raised per year. on in their natal territory The five to nine eggs are white with reddish brown dots. and help their parents rear The female incubates them, and the male brings her food. the next year's brood. The eggs hatch after 12 days. Juveniles beg loudly and are fed by both parents. Young fledge about 16 days after White-Breasted hatching. Some three to four weeks after fledging, the young Sitta ( Nuthatch suddenly disperse, moving off in random directions. As carolinensis ) — The winter approaches, they join feeding flocks. Some become white-breasted "floaters," moving between three or more flocks, ready to nuthatch has a pair with an opposite-sex bird should its mate die. slate-gray back, a Chickadees are taken by many predators including sharp- shinned hawks, American kestrels, Eastern screech owls, saw whet owls, and domestic and feral cats. Sometimes zee-zee-zee chickadees mob these enemies while sounding alarm calls. The average life span for a chickadee is two and a half years, and the current longevity record is 12 years, nine months. Every few years long-distance movements take White-Breasted place within the population, "irruptions" that may be launched by failure of seed crops or high reproductive success. Nuthatch Poecile carolinensis ( Carolina Chickadee ) — Similar to the black-capped chickadee in appearance and life history, this species lives in milder climates across the southeastern United States. The Carolina chickadee breeds in southeastern and southwestern Pennsylvania.
26 produced in a single annual brood. In some autumns, large numbers of red-breasted nuthatches show up south of their normal range; biologists believe that poor cone production in northern forests drives these movements. Certhia americana ) — Brown creepers Brown Creeper ( are inconspicuous birds whose intricately patterned backs help blend them in with the tree bark that is their near-perpetual home. Brown creepers breed across a huge range extending from Alaska and Newfoundland south to Red-Breasted Nicaragua. They favor mature forests with many large trees. The species is found in much of Pennsylvania, although Nuthatch numbers are lower in the state's southeastern and southwestern corners. Braced by their long stiff tails, brown creepers white breast and face, and a cap that is black in the male climb slowly up tree and ashy gray in the female. Nuthatches inhabit deciduous Brown Creeper trunks, following a forests throughout Pennsylvania and the East. They climb spiral course. They around in trees, walking in a herky-jerky manner up and inspect bark furrows down and around the trunks, along branches and the and use their call. undersides of limbs. Both sexes sound a nasal ank ank decurved bills to Pairs live in home territories of 20 to 35 acres. tease out insects, White-breasted nuthatches feed on insects and spiders pupae and eggs. in summer and on nuts and seeds in winter. They relish suet They also eat spiders at feeding stations and carry away sunflower seeds for caching. and seeds. Sometimes they forage on the ground. Nuthatches wedge The call is a long, acorns and hickory nuts into tree bark and then hammer seeee thin ; the male the shells off with blows from their awl-like beaks. also voices a subtle During courtship, the male bows to the female, spreading breeding song. The his tail and drooping his wings while swaying back and forth; species nests under he also feeds her morsels. Before building the nest, the birds peeling bark, often in rub or sweep crushed insects back and forth over the inside a shagbark hickory or and outside of the nest cavity. Ornithologists speculate that a dead or dying tree, this sweeping behavior leaves chemical secretions behind less frequently in a that may repel predators or nest competitors. The female cavity. builds a nest inside the cavity (commonly a rotted-out branch A hammocklike stub or an abandoned squirrel or woodpecker hole) using twig nest is built to fit twigs, bark fibers, grasses and hair. She lays five to nine white, the available space. brown-spotted eggs and incubates them for 12 to 14 days The female lays four while her mate brings her food. Both parents feed insects to eight eggs, which and spiders to the young, which fledge after two or three are whitish and weeks, usually in June. dotted with reddish brown. Incubation Red-Breasted Nuthatch ( Sitta canadensis )—In takes 14 to 17 days, Pennsylvania, this species is found mainly in the northern and young leave the part of the state; it ranges through New England and across nest two weeks after Canada. Slightly smaller than the white-breasted nuthatch, hatching. Brown the red-breasted has a rusty tinge to its breast and a creepers from the Northeast may migrate south to Florida prominent black eye-stripe. The species lives in areas where and the Gulf Coast. In winter, brown creepers sometimes evergreens are plentiful and often nests in pine plantations. mix in with foraging flocks of chickadees; perhaps these Red-breasted nuthatches feed on insects and on seeds, are residents, or northern birds that have shifted particularly those of conifers. They nest in tree cavities 5 southward. to 40 feet above the ground. Five or six young are
27 Wildlife Notes Allegheny Woodrat Opossum Bats Otter Beaver Owls Black Bear Porcupine Blackbirds, Orioles, Cowbird and Starling Puddle Ducks Blue Jay Raccoon Bobcat Rails, Moorhen and Coot Bobwhite Quail Raptors Canada Goose Ring-necked Pheasant Chickadees, Nuthatches, Titmouse and Brown Ruby-throated Hummingbird Creeper Ruffed Grouse Chimney Swift, Purple Martin and Swallows Shrews Chipmunk Snowshoe Hare Common Nighthawk and Whip-Poor-Will Sparrows and Towhee Cottontail Rabbit Squirrels Coyote Striped Skunk Crows and Ravens Tanagers Diving Ducks Thrushes Doves Vireos Eagles and Ospreys Vultures Elk Weasels Finches and House Sparrow White-tailed Deer Fisher Wild Turkey Flycatchers Woodchuck Foxes (Red & Gray) Woodcock Gray Catbird, Northern Mockingbird and Wood Duck Brown Thrasher Woodpecker Herons Wood Warblers Kingfisher Wrens Mallard Mice and Voles Wildlife Notes are available from the Minks & Muskrats Pennsylvania Game Commission Bureau of Information and Education Northern Cardinal, Grosbeaks, Indigo Bunting Dept. MS, 2001 Elmerton Avenue and Dickcissel Harrisburg, PA 17110-9797 www.pgc.state.pa.us An Equal Opportunity Employer
28 Wildlife Note — 53 LDR0103 Chimney Swift, Purple Martin and Swallows Chimney Swift by Chuck Fergus Swifts, martins and swallows are built for life in the air. They have long tapering wings and light- ( Chimney Swift Chaetura pelagica ) — The common weight bodies. Their short, wide bills open to expose gap- name comes from the bird's favorite nesting habitat and ing mouths for scooping up insect prey. The chimney swift the speed of its flight. A chimney swift is sooty gray, about belongs to Family Apodidae, with 90 species worldwide. five inches long, and has a one-foot wingspan; the body The purple martin and the swallows are in Family looks stubby between the long, narrow wings. The bird Hirundinidae, also with about 90 species around the spends most of the daytime hours in the air; its flight is globe. The chimney swift has tiny, vestigial feet with four bat-like, with shallow wingbeats and erratic stalls and clawed toes facing forward, letting it cling to upright sur- turns as the bird singles out insects or sweeps through faces; the feet of the purple martin and the swallows have clouds of prey. A loud clicking call is uttered in flight. three toes forward and one to the rear, for perching on Chimney swifts eat flies, leafhoppers, flying ants, may- branches and wires. flies, stoneflies, beetles, leaf bugs and other flying insects. Many of these birds are social and breed in colonies. They take spiders, mainly small ones floating on strands Purple martins usually nest in artificial boxes with mul- of silk borne aloft by air currents. Chimney swifts drink tiple chambers, put up by people wanting to attract these on the wing, skimming low over ponds, and they even insect eaters; the other swallows build or occupy differ- gather materials for their nests while in flight, using their ent sorts of nests, depending on their species. Most swal- feet to break tips off dead branches and carry them back lows do not defend territories. The males sing mainly to to the nest site. attract and communicate with females. Both parents usu- Chimney swifts are thought to be monogamous and ally share in incubating eggs and feeding young. Swifts, to mate for life. Pairs sometimes glide in tandem with martins and swallows often forage in groups, soaring their wings raised in a V. In the past, chimney swifts nested above forests, farms and urban areas. During wet weather in hollow trees and caverns. Today they use manmade they hunt at lower altitudes, where insects fly under damp structures almost exclusively: factory and house chim- conditions. These birds undertake long migrations. The neys, silos, air shafts and old wells, where they are pro- seven species that breed in Pennsylvania winter in the tected from storms and predators. The nest is shaped like Gulf states, Central America and South America.
29 Tree Swallow ( Tachycineta bicolor ) — Tree swallows a half-saucer and cemented to a vertical surface, the twigs nest across Canada and most of the northern United held together by the adults' glutinous saliva, which so- States. They are five to six inches long, an iridescent lidifies and binds as it dries. Females lay three to six eggs green-black or blue-black above and bright white be- (four or five are usual), which are white and unmarked. low. They nest in tree cavities, woodpecker holes and Both sexes participate in the 18- to 21-day incubation. bluebird houses put up by humans. The The newly hatched young are altricial and are fed regur- earliest of our swallows to return gitated insects. Sometimes a third "parent," probably a Tree Swallow north, they arrive in late March yearling offspring of the adults, helps to feed and brood and April; unlike the other nestlings. The young fledge a month after hatching and species, tree swallows join feeding flocks. In late summer swifts gather in the switch to eating ber- evening before flying into large factory chimneys, where ries and seeds to they roost by the thousands. survive cold Chimney swifts are not common in the densely periods when wooded parts of Pennsylvania, where trees may not be insects become mature enough to offer cavities for nesting and roosting. torpid. They of- Swifts arrive in the Northeast in May, raise a single brood ten breed near in June and July, and head south in August and Septem- the still waters of ber. They winter mainly in the Amazon Basin. The aver- lakes, ponds and age lifespan is four years. marshes, compet- ing for nest cavi- Purple Martin ( Progne subis ) — At eight inches in ties with blue- length, the martin is the largest North American swal- birds, starlings, low. Adult males are a glistening blue-black; females and house sparrows and yearlings are grayish with pale bellies. Both sexes have a house wrens. Orni- notched tail. Martins, less maneuverable than other swal- thologists believe lows, glide in circles punctuated with short periods of that individuals flapping flight. Before Europeans came to the New World, choose new mates native Americans were hanging gourds around their vil- each year. Tree swal- lages to attract purple martins, which also nested in caves lows are more aggres- and hollow trees. In sive than other swal- Pennsylvania today, low species and defend the vast majority an area within a radius of martins nest of about 15 yards from the nest. colonially in The female lines the nest cavity with grass, weeds, rootlets and pine needles; after the four to seven pink- ish-white eggs are laid, she often adds feathers (usually white ones) from other birds. Incubation takes 14 to 15 days. The young fledge three weeks after hatching. Tree swallows migrate in flocks to wintering grounds in the Gulf states and Cen- tral America. Northern Rough-winged Swallow Stelgidopteryx ( ) — This small serripennis Purple Martin (body length, about five inches), nondescript brown and white swallow is named compartmented for small serra- boxes that people put up for them. Martins tions in its outer- inhabit open areas near water, meadows and farmland. most wing feath- They feed on winged ants, wasps, bees, flies, dragonflies, ers. The species beetles, moths and butterflies. Males arrive first in the breeds across the spring, followed by females. The call is a throaty, gur- United States and gling tchew-wew . One male may mate with more than one in Central female. The four or five eggs are white and unmarked, America. Rough-winged laid on a nest of grass, twigs and leaves inside the nest Northern swallows often forage in chamber. Flocks of martins gather by the thousands in Rough- flight above moving water. August and September prior to migration. The female winged trit The call is a short, harsh incubates them for 15 to 18 days. The species winters in . The birds nest in cavi- bit the Amazon Basin. Swallow
30 instance, 800 nests were clustered on the side of a barn. ties in rock faces, quarries and stream banks, frequently The adults line the inside of the nest with grass, hair and in abandoned kingfisher burrows, drainpipes and culverts; feathers. The three to six eggs are white spotted with sometimes they excavate their own burrows. At the end brown. Both sexes incubate for about 15 days. A female of a one- to six-foot tunnel, the birds heap up twigs, bark, cliff swallow will sometimes lay an egg in another swallow's roots and weeds, and line a central cup with fine grasses. nest, or carry an egg in her bill to a neighboring nest. Cliff The four to eight pure white eggs hatch after about 16 swallows winter in southern South America. The popula- days of incubation. Rough-winged swallows nest through- tion is thought to be increasing in North America. out Pennsylvania, rarely in colonies. They winter along the Gulf Coast and in Central America. ) — The flight of these ( Barn Swallow Hirundo rustica ) — About 5½ inches Bank Swallow ( sleek, long-tailed blue-and-buff swallows can look like Riparia riparia an aerial ballet, with the birds sideslipping, stalling, twist- long, this small brown-backed swallow has a dark band ing and turning low over water or fields in pursuit of their across its pale breast. Although they have small feet and prey: house flies, horse tiny bills, bank swallows usually dig their own burrows, flies, beetles, wasps, up to five feet deep in dirt banks, piles of gravel or sand bees, winged ants and and roadcuts. Nest entries of neighboring pairs may be Barn Swallow others. In bad only a foot apart. Colonies arise and die out as banks of suitable burrowing weather, barn swal- lows may land and materials be- eat spiders, snails, come available Bank Swallow berries or seeds. and then lose Pairs nest on qualities that their own, or near bank swallows a few other pairs. require, such Barn swallows as steepness are common, and height. abundant breed- Bank swallows forage over ing birds in Penn- sylvania and the fields and wet- lands and along Northeast. They rivers and ponds, build bowl- shaped nests out taking flies, of mud and beetles, wasps, straw, fixing them winged ants, drag- to walls, beams and onflies, stoneflies, eaves of barns and moths and other flying insects. They nest from May until other outbuildings; in July. The clutch averages four or five eggs. In late sum- mer bank swallows may gather in large flocks before de- culverts and under bridges; and rarely on the cliff faces and caves which were the species' original habitat before parting for wintering grounds in South America. The spe- Europeans settled North America. Barn swal- cies also breeds in Europe and Asia, where it is known as the sand martin. lows often line their nests with poultry feathers. The adults scold human intrud- ( Hirundo Cliff Swallow ers and dive at them, zipping past their pyrrhonota ) — Body length, five to heads. Most females lay four or five eggs, six inches; a pale rusty or buff-col- which are white spotted with brown. Dur- ored rump distinguishes this spe- ing the day both male and female take cies. From below, the tail looks turns incubating, switching about ev- squared-off. Cliff swallows eat fly- ery 15 minutes. Young leave the nest ing beetles, flies, winged ants, three weeks after hatching. Some bees, wasps, mayflies, lacewings pairs raise a second brood. and many other insects. They Barn swallows from eastern build gourd-shaped nests out of North America winter in pellets of mud, attached to Panama, Puerto Rico and cliffs, bridge supports, dams throughout South and walls of unpainted barns Hirundo rustica America. and derelict buildings under is the most widespread eaves that protect against swallow species in the rain. A typical nest takes world, breeding in North one to two weeks to build America, Europe and and requires more than Asia. 1,000 mud pellets. Colo- Cliff Swallow nies can be dense: in one
32 Wildlife Note — 55 LDR0103 Common Common Common Common Common Nighthawk and Nighthawk and Nighthawk and Nighthawk and Nighthawk and Nighthawk Whip-Poor-W Whip-Poor-W ill ill Whip-Poor-W ill ill Whip-Poor-W Whip-Poor-W ill By Chuck Fergus The common nighthawk and the whip-poor-will than 50 insect species have been reported as prey, in- belong to Family Caprimulgidae, a group of nocturnal cluding flying ants, June bugs, mosquitoes, moths, may- and crepuscular birds also known as the nightjars; 80 spe- flies, caddisflies, wasps and grasshoppers. Nighthawks cies are found around the world. Nightjars have large drink on the wing, skimming the surface of lakes and heads and eyes and exceedingly wide mouths, used as streams. They do not fly during heavy rain, strong winds scoops for catching insects in midair. Their long wings or cold weather. and large tails contribute to a buoyant, maneuverable The call is a loud, nasal Peent which, according to flight. Their legs are short, and their feet are small and one source, resembles the word "beard" whispered loudly. weak. Most spend the day resting on the ground or roost- As part of his breeding display, the male also makes a ing in trees, perched lengthwise on limbs. "Nightjar" booming sound, which is produced by air rushing through seemingly refers to the birds' nocturnal habits and the his primary wing feathers after a sudden downward flex- jarring or grating aspect of their vocalizing. The night- ing of the wings while diving. Years ago, while camping jars are also known as "goatsuckers," from an erroneous at a back-country site in the Badlands National Park in belief that the birds use their expansive maws to steal South Dakota, I sat enraptured by nighthawks "boom- milk from goats and other livestock. ing" above the prairie through the extended twilight of a June evening and on into moonlit night. Common Nighthawk ( Chordeiles minor ) — The Chordeiles minor has a large breeding range, from name "nighthawk" is a misnomer, as the bird is not re- the Yukon Territory to Labrador and south to Florida, lated to the hawks and it flies mainly at dawn and dusk Texas and Central America. The birds nest in open fields, rather than at night. A nighthawk is about nine inches gravel beaches, rock ledges, burned-over woods, grass- long, with a wingspread of almost two feet; individuals lands and flat graveled roofs of buildings such as schools weigh from two and a half to three and a half ounces. and grocery stores. The female nighthawk does not build The flight pattern is bouncy, erratic, full of twists and a nest; she lays her two eggs directly on the ground. The turns. Nighthawks spend the summer in many cities and laying period peaks around the first of June. Nighthawk small towns across the state. During late summer eve- eggs are creamy or pale gray, dotted with brown and gray. nings many people see flocks of nighthawks flying high The female does most of the incubating (the male may above towns and farmland, but few have gotten a close spell her at times), and the eggs hatch after about 18 look at the birds. The plumage is a mix of dark gray and days. Nestlings are "semi-precocial": their eyes are open brown. The long wings have a crook about halfway out and they are able to move from side to side after hatch- and then taper to a point. The tail has a white band; white ing. Females may feign injury to draw predators away brightens the chin and throat; and a white "bandage" on from the nest. Both parents feed the chicks by regurgi- each wing is clearly visible from below. tating insects to them. At around 18 days, young night- Unlike whip-poor-wills, which sit in wait and then hawks make their first flights. They can fly capably by 30 sally forth to catch individual insects, nighthawks remain days, and by 50 days they are fully developed. Night- on the wing for extended periods, flapping, gliding, stall- hawks raise only one brood per year. They are among the ing and swerving as they chase and catch prey. Their bat- earliest breeding birds to leave Pennsylvania, commenc- like flight has earned them the nickname "bullbat." More ing their southward migration in August.
33 or early May, when males arrive from the south; the call- The average life span of a common nighthawk is ing continues through June and dwindles in July. Whip- estimated at four to five years; banded birds as old as poor-wills call mainly at dawn and dusk, and they go on nine years have been recovered. Since the 1960s the and on. A friend of mine who lived on our road, upon number of breeding and migrating nighthawks has fallen hearing a whip-poor-will start up outside his house, noticeably. This decline may stem from indiscriminate counted for four consecutive minutes, recording 55, 56, use of pesticides, increased predation, or changes in habi- 56 and 57 repetitions. He noted the time, then sat read- tat, either in the northern breeding range or in the south- ing. The bird kept singing, without changing position or ern wintering area, which includes South America, about tempo, for 91 minutes. Figuring an average of 56 calls which little is known. In Pennsylvania most nesting takes per minute, he arrived at a total of more than 5,000 whip- place on building roofs in urban areas, with nighthawks poor-wills . seemingly abandoning traditional rural nesting sites. The calling attracts females. Whip-poor-will court- ship involves head-bobbing, bowing and sidling about Whip-Poor-Will ( Caprimulgus vociferus ) — The on the ground. The female lays two eggs on the ground whip-poor-will lives in moist woods across the eastern in dry open woods, often near the edge of a clearing. Most and southern United States. It is about the size of a com- egg-laying occurs between mid-May and mid-July. The mon nighthawk, but its wingspan is not as great and its eggs are off-white, speckled with tan, brown or lilac; they wings are broader and more rounded. On each side of blend in with the dead leaves, as does the adult that in- the bill, a vertical row of hair-like bristles flares toward cubates them. Several times I have almost stepped on the front: the bristles funnel insect prey into the gener- whip-poor-wills incubating or brooding. In one case the ous mouth. The plumage is a mix of camouflaging browns. incubating bird was a male. On another occasion the Both sexes have a white neck band, and the male has adult, a female, flew directly at my face, then fell to the white outer tailfeathers. ground and tried distracting me by feigning an injury. Whip-poor-wills perch on branches or sit on the The reproduction of whip-poor- ground or along roadsides, where the birds' eyes gleam wills may correlate with the lunar red or bright orange in the cycle: males sing longer on moonlit glare of automobile head- nights, and hatching may occur lights. This "eyeshine" is when the moon is waxing, on its way caused by a reflective layer at to being full, so that the increased the back of the retina called light makes foraging easier for the the tapetum. The tapetum adults, which must now feed nest- amplifies small amounts of light lings as well as themselves. The by passing them back through the eggs hatch after about three weeks retina a second time. Whip-poor-wills of incubation. Parent birds feed fly up to catch moths, mosquitoes, gnats, their young by regurgitating crushed June bugs and crane flies. The sit-and-wait Whip-Poor-Will insects. The fledglings first fly about foraging strategy is less energy-expensive 20 days after hatching. Whip-poor-wills than the common nighthawk's in-flight forag- begin leaving the Northeast in August and September, ing and may be what allows whip-poor-wills to arrive ear- with stragglers into October. The species winters in the lier on northern breeding grounds and to survive peri- southeastern states, in areas where the related chuck- ods of cold weather and low prey availability. Its soft will's-widow ( ) breeds in summer. Caprimulgus carolinensis feathering lets a whip-poor-will fly almost as quietly as (The chuck-will's-widow withdraws to Central and South an owl and helps the bird intercept moths, many of which America in winter.) Some whip-poor-wills migrate to can detect, through tympanic membranes, sounds of po- Central America and the West Indies. tential predators. Whip-poor-wills take sphinx moths, Whip-poor-wills reach their greatest numbers in noctuid moths and the big silk moths: cecropia, tuna and young brushy forests; abandoned farms, sometimes called polyphemus. "whip-poor-will farms"; and woodland edges, where rank The whip-poor-will is named for the male's repeti- plant growth promotes insect populations. The birds hunt tive nocturnal calling. The "whip" is sharp, the "poor" in forest clearings and around water, orchards and gar- falls away, and the "will" — the highest note in the se- dens. In Pennsylvania the population remains strongest quence — is a bullwhip snapping in the night. The call in the Ridge and Valley Province in the southcentral carries about half a mile. Listeners close to the calling counties. The whip-poor-will does not adapt well to ur- bird may hear a soft sound before each repetition. knock banization; the growth of suburbs In Pennsylvania whip-poor-wills start calling in late April and cities has eliminated this species from much of south- Wildlife Notes are available from the eastern Pennsylvania. Pennsylvania Game Commission Whip-poor-wills also cease Bureau of Information and Education to breed in areas where Dept. MS, 2001 Elmerton Avenue woods become too mature; Harrisburg, PA 17110-9797 they have declined over www.pgc.state.pa.us much of the East during the last three decades. An Equal Opportunity Employer
34 Wildlife Note — 4 LDR0103 Cottontail Rabbit by Chuck Fergus The cottontail rabbit, Sylvilagus floridanus , is prob- of speed and a zigzagging running pattern to evade preda- ably our most popular small game animal, and it's also tors, but they cannot run steadily for long distances. They the wild animal most often seen in towns and suburban can swim if they have to. areas. Because of its popularity and conspicuousness, the Cottontail litters are usually born from March through rabbit arouses interest both in those who hunt and those September, with about half the total litters being born in who simply enjoy nature. May and June. Litter size ranges from two to nine young, with five the average; the gestation period is about 28 Biology days. Each mature female bears an average of four litters per year. Juvenile females born in early spring are sexu- The cottontail rabbit is a long-eared, small- to me- ally mature — and often breed — by late summer of the dium-sized mammal of the family Leporidae. It hops when same year. running, because its hind legs are longer than its front A cup-shaped depression about five inches across and legs. A rabbit's soft fur is brownish above and white be- four to six inches deep serves as a nest. It's lined with low, it has a conspicuous 2-inch-diameter white tail, and dried grasses and fur, which the female plucks from her some individuals have a small white blaze on the fore- chest and belly. Young are born blind, naked and help- head. Cottontails are 15 - 18 inches long and weigh two less, but they develop rapidly and are weaned, fully furred to three pounds, with females slightly heavier than males. and on their own when 16 days old. The male takes no Preferred habitat includes swamps, thickets, briar part in raising the young. Predators, spring floods, heavy patches, weedy fields, brush piles, overgrown fencerows rains and farming operations are major causes of nest and brushy gullies. Feeding areas are rarely very far from mortality. good cover. Rabbits seldom dig dens, preferring to oc- Few cottontails live to be more than a year old in the cupy abandoned woodchuck burrows. Home range may wild, although their potential life span is three to four be a quarter-acre to 20 acres, depending on the avail- years. Rabbits are a major food source for many other ability of food and cover. An individual rarely leaves its types of wildlife. Like other heavily home territory, where it knows food sources, cover and preyed upon species, rabbits have an escape routes thoroughly. extremely high reproductive rate Summer foods include leaves, herbs, legumes, fallen which maintains adequate fruit, garden vegetables, low broad-leafed weeds, clover populations. and grass; captive wild rabbits have eaten grass equiva- lent to 42 percent of their weight daily during summer. Population In winter, cottontails eat blackberry and raspberry canes, bark, buds, tender twigs of bushy plants and poison ivy The rabbit vines. population to- A rabbit possesses sharp hearing and a keen sense of day is not as smell. Its eyes are set well back on the sides of its head, large as it was in providing a wide field of vision. Rabbits are basically the past. The pri- nocturnal, feeding in the evening, at night and in the mary reason for early morning. Individuals shelter in thick brush or aban- this decline is doned woodchuck burrows during the day, and they lead loss of good solitary lives on their home ranges. Rabbits rely on a burst habitat. Today's
35 Habitat modern equipment lets farmers clean up and cultivate fencerows, swamps and brushy slopes that once held many rabbits. Expanding cities and towns, new roads and dams Habitat has more impact on the rabbit population than also reduce habitat or degrade its quality. any other factor. Good rabbit habitat provides abundant Around the turn of the 20th century, many forest ar- food and protective cover. Heavily cultivated land pro- eas were logged off. As these areas grew into brush, new duces ample food, but often not enough protective cover. rabbit habitat was formed, resulting in tremendous cot- On abandoned farming land, the reverse of this often tontail populations. Later, low brush veg- holds true. etation — which supported the large Rocky field corners, gullies, poorly- rabbit populations — began to drained woodlands, outcrops and other ar- die as it was shaded out by eas not being farmed can be managed to growing trees. This loss of produce rabbits. These areas may be low vegetation is a result of planted with pines or shrubs. Cutting normal forest succession. along woodland edges stimulates the From year to year, rabbit growth of low vegetation; brushy plants populations fluctuate in a given that will grow in these cut-over areas area. Changes seem to follow a provide food and cover for several smooth curve, indicating gradual years. population increases and de- Individuals interested in creating creases. Hunters usually har- more summer food for rabbits can vest less than 30 percent plant areas of clover and grasses. of the available rabbits. These food plots may require four Studies show that even or more mowings each summer to if hunters take as many keep them in a "lawn" condition, as 40 percent of the rab- and they should also be located bits available in autumn, near good cover. the next year's rabbit Rabbits like to take shelter in population will not be brushpiles. Brushpiles are best made adversely affected be- by placing smaller brush over several cause of the species' tre- firm, large logs, which provide support. The mendous reproductive po- larger logs also keep the brush off the ground, prevent- tential. Young rabbits usually ing its rapid deterioration. comprise about 80 percent of the population, but few Many conifers also produce fine cover, including white, live to see their second winter. red, Scotch, Virginia, Australian and mugho pines, and In summer, when litters are being born and food is Norway spruce. Coniferous plantings require mainte- plentiful, four rabbits may inhabit a single acre. Then an nance to remain good cover areas. Information on the apparent change takes place in early fall. The summer's best methods of planting, spacing and maintaining plants surplus of young rabbits has been thinned by disease, pre- for food and cover is available from the Game Commis- dation, accidents and parasites. During the fall, one rab- sion. bit per acre is considered a good density. The popula- Most of Pennsylvania's small game is produced on pri- tion is at its ebb in late winter after hunters, predators vate land, and the key to a larger rabbit population is and weather have taken many rabbits. more habitat improvement by private landowners. Wildlife Notes are available from the Pennsylvania Game Commission Bureau of Information and Education Dept. MS, 2001 Elmerton Avenue Harrisburg, PA 17110-9797 www.pgc.state.pa.us An Equal Opportunity Employer
36 Wildlife Note — 12 LDR1105 Crows and Ravens by Chuck Fergus sight and hearing. They are wary and usually post sen- Crows and ravens belong to the large family Corvidae, tries while they feed. Sentry birds watch for danger, ready along with more than 200 other species that includes jays, caw . Once to alert the feeding birds with a sharp alarm nutcrackers and magpies. Their subfamily, the Corvinae, aloft, crows fly at 25 to 30 mph; with a strong tail wind, is represented in Pennsylvania by three species: Ameri- they can hit 60. These skillful fliers have a large reper- can crow, fish crow and common raven. These less-than- toire of moves designed to throw off airborne predators. melodious birds, you may be surprised to learn, are clas- Crows are relatively gregarious. Throughout most of sified as songbirds. the year, they flock in groups ranging from family units to several hundred birds. During winter, crows may gather ( ) — Crows American Crow Corvus brachyrhynchos by the tens of thousands in areas where food is plentiful. are some of the most conspicuous and best known of all Later, these flocks break up as mate selection takes place. birds. They're intelligent, wary and adapt well to human Males vie for mates through fighting and spectacular activity. As with most other wildlife species, crows are flight routines. Once paired, male and female search out considered to have "good" points and "bad" ones — value a secluded woodlot to raise their brood. Both sexes share judgements made strictly by humans. They're found in nest-building and egg-incubating chores. Some natural- all 50 states and parts of Canada and Mexico. ists believe crows mate for life. A nest site is usually chosen away from those of other Biology crows. Most often, nests are built in the crotch of a tree, 10 to 70 feet above ground, usually more than 25 feet. A Also known as the common crow, an adult American typical crow's nest is a large, substantial basket, 22 to 26 crow weighs about 20 ounces; its body length is 15 to 18 inches across, built of twigs, sticks, bark and vines. The inches and its wings span up to three feet. Both males deep central cup is lined with moss, shredded bark, grass, and females are black from their beaks to the tips of their deer hair, fur, feathers or similar material. tails. Their feathers are iridescent, flashing highlights of After mating, the female lays 3 to 8 eggs (usually 4 to blue, green and purple. Albinism occurs, producing pure 6) in April or partial white coloration. The scientific species name, and May. brachyrhynchos , means "short beak;" actually, the crow's beak is fairly large, 2½ inches long and quite sturdy, but short compared to that of the closely related raven. Crows are found in Pennsylvania year-round. This doesn't mean the same individual birds are here all the time: Crows that breed here migrate south, starting in late September or early October, and are replaced by birds from the north. Northern migrants remain in our state over winter while crows born in Pennsylvania fly as far south as the Gulf of Mexico. Flocks of crows range widely for food, up to 30 miles a day in winter. Foods include grasshop- pers, caterpillars, grubs, worms, most insects, grain, fruit, the eggs and young of other birds, organic garbage — just about any- thing that they can find or overpower. Crows also feed on the carcasses of winter- and road-killed animals. Crows have extremely keen senses of
37 is abundant. Here, they may group into flocks of thou- Eggs are oval, bluish-green, and blotched and spotted sands of birds that congregate nightly at roosts — spots with brown and gray. The young hatch following an 18- where crows have sometimes gathered together for de- day incubation period. cades. Each day, crows fly in different directions from Ten days after they hatch, the young crows are almost the roosts, feed and return at night. Most birds usually fully feathered, and their eyes are open. They leave the leave and return along the same route each day. nest at five weeks of age, and look like small adults. Young The crow is classified by the federal government as a birds follow, imitate and learn from their parents all sum- migratory nongame bird. It's the only bird in this classi- mer. Often the family group sticks together until the fol- fication that may be hunted. Except in Hawaii, where lowing spring. crows are protected, they may be hunted during estab- Crows are both predators and prey. As predators, they lished seasons which may not exceed 124 days per year. rob nests of songbirds and waterfowl, killing and eating States are prohibited from establishing seasons during newly hatched young, or cracking eggs. As prey, young the peak nesting period. Individual states set season dates crows and unhatched crow eggs are eaten by raccoons, and regulate hunting methods, bag limits, etc., under opossums and tree-climbing snakes. Hawks and owls kill regulations set by the U.S. Fish and Wildlife Service. fledgling and adult crows. Crows are especially vulner- able to night attacks by great horned owls. Habitat If crows locate an owl during the day, they will mob it — swooping low, calling excitedly and Crows get along in extremely varied habitat. They attracting other crows, and generally thrive everywhere, from the semi-arid regions of the west harassing the bigger, less maneu- Raven to the big timber land of the north. They probably pre- verable bird. They also mob fer farmland, but are also found in parks, on hawks. In turn, crows are wooded islands, in wooded areas on the fringes mobbed by smaller birds, of towns and, increasingly, even in our especially kingbirds largest cities. and red-winged Generally, crows are blackbirds. most numerous in agricul- Crows are curi- tural districts with a great ous. Shiny objects variety and plentiful supply fascinate them, and of food. One habitat neces- they have been sity is an adequate number known to fly off with bits of trees for cover and nest- of glass, rings, keys, etc. Crow ing sites. Farm woodlots are Crows exhibit their intelli- ideal for this. Nests built gence by imitating a large num- and abandoned by crows ber of sounds, including whistles, sometimes provide habitat for birds that, ironically, are cats, machines and the human voice. Crows have a good one of the crow's age-old enemies: the great horned owl. coos , crowing noises, caws vocabulary — a wide range of , There's plenty of suitable habitat for crows across the and other soft, melodious sounds they use to communi- country today. Undoubtedly, the species will be with us cate with each other. indefinitely — especially since more and more people have a better understanding of crows and the beneficial Population services they provide. Crows not only live alongside man, they've survived ( Corvus ossifragus) Fish Crow — which means "bone in spite of him. Because of their habits of pulling up corn breaker," never strays too far from the Atlantic and Gulf shoots and occasionally robbing game bird nests, crows coasts and tributary rivers. Its Pennsylvania distribution have been persecuted. Today, however, humans also rec- centers in the southeast and along the Susquehanna River, ognize the crow's beneficial side — in helping control including the West Branch to Lock Haven and Centre harmful insects such as tent caterpillars, locusts and white County's Bald Eagle Creek (a tributary), and up the grubs, in cleaning up dead road-killed birds and animals, Susquehanna's North Branch to Scranton. Where it oc- and even our improperly disposed garbage. curs, it's fairly common, but it's probably often confused Some estimates put the crow population at more than with the common crow. If the two are seen together, the three billion in North America. Their numbers may be fish crow can be distinguished by its smaller size. Other- affected by man-made substances such as aldrin, dield- or car wise, the best identifier is its call, a short, nasal rin, heptachlor and DDT that have been introduced into caw cah-cuh , as opposed to the distinct of the common the environment (All are now banned). These insecti- crow. (A young common crow, however, may sound like cides accumulated and are still found in natural food a fish crow, so it's difficult to distinguish the two species chains and in some bird species caused local reproduc- in late spring and summer.) tive failure or thin eggshells that break during incuba- As its name implies, this bird feeds on fish; however, tion. However, it's speculative whether this is the case it also eats a variety of other foods. Along the shore, it with crows. captures fish and small crabs, sometimes steals food from Each year, many crows winter in southern Pennsylva- the smaller gulls and terns, and scavenges for whatever nia, where weather conditions are relatively mild and food
38 ance with a longer, wedge-shaped tail, proportionally longer it can find. Inland, the fish and common crows often feed wings, and a long head and bill. Their longer wings are even together, frequently in agricultural fields. Other songbirds' evident when ravens are standing or walking. They can be eggs and nestlings occasionally fall prey to the fish crow. recognized by their distinctive head profile or flight silhou- Nest and eggs are very similar to, though a bit smaller ette alone. By contrast, crows seem to have broader wings and than, those of the common crow. Like their cousins, fish shorter, squared-off tails. Side by side, crows are much sleeker crows build their nest in trees. than the more robust ravens. Ravens are better equipped and more likely to soar than are crows, using their wedge-shaped Common Raven Corvus corax ) — is an uncommon ( tail to catch the wind. Ravens engage in spectacular aerial Pennsylvania resident found mainly in the mountainous acrobatics, including flips, loops, rolls, and dives. Males will northcentral region. Once more common, by the late 19th carry large sticks in flight while in courtship and nest-build- century it was so rare some considered it to be possibly ing. extinct in this state. Today, the raven population is re- Ravens eat rodents, insects, grain, fruit, bird eggs and refuse. covering and expanding into the Poconos and our south- They consume much carrion, especially in winter. In north- central and southeastern counties. Ravens are abundant ern Pennsylvania, they are often seen along Interstate 80, in Canada and the Rocky Mountains. Favored habitat is where they feed on road-killed deer, raccoons, opossums, etc. remote, heavily forested wilderness, seacoasts and wooded Ravens also prey upon sick and injured animals. islands. A raven is every bit as alert as a crow and possesses sharp Ravens are 20 to 25 inches in length, with a wingspread eyesight and hearing. Ravens are considered among the most of about four feet. Their plumage is entirely black, with intelligent of all birds; like crows, they can learn to imitate a green and purple iridescence. Both sexes are colored alike; variety of sounds, including the human voice. In nature, their males are generally larger than females. calls include guttural croaks, gurgling noises, and a sharp, The raven is often confused with its close relative, the tock metallic " ." crow, but there are major differences between the two species Ravens are skillful fliers; their courtship display flight that are especially apparent when crows and ravens are seen is especially spectacular. After mating, a pair will seek together. Ravens are much bulkier than crows, being over out an isolated nesting spot, usually at least a mile away twice their weight, and more hawk-like in appearance and from any other ravens. Nests are built on cliffs or near the tops habit. Ravens have a massive bill that equips them better for of large trees. Of 17 raven nests found in Pennsylvania, 13 predation and scavenging. The raven's head profile with a were on cliffs, three were in hemlocks (45 to 80 feet up), and large, bulky bill and shaggy throat are characteristic field one was 85 feet up in a white pine. marks. In flight, ravens also have a more elongated appear- Ravens often build a new nest on top of the previous year's nest. Nests are constructed of large sticks, twigs and grapevines. Outside diameter is 2 to 4 feet; inside diameter, one foot; depth of central hollow, six inches. The central hollow is lined with deer hair, moss, shredded bark and grass. Family Tree The female lays 3 to 6 (usually 4 to 5) oval eggs, which are greenish and covered with brown or olive markings. Eggshells are rough and dull-looking. Incubation, which is mainly by the fe- male, lasts about three weeks. Young are altri- cial. They leave the nest about one month after hatching. Ravens seem to need seclusion for successful reproduction, but they are becoming more tol- erant of people. Each year, more seem to be nesting in closer prox- imity to civilization and entering towns in winter to feed on litter and garbage. Ravens may live as long as 35 years in the wild, but much less is normal.
39 Wildlife Note — 34 LDR0603 Diving Ducks by Chuck Fergus Pennsylvania ducks may be grouped into two types: ducks must run across the water to build up speed before diving ducks and puddle ducks. Diving ducks spend much taking off. more of their time farther out from shore than puddle Diving ducks, puddle ducks, geese and swans begin ducks. Both groups can be found on streams, rivers, lakes migrating north through Pennsylvania in late February. and marshes. This note covers 15 species commonly Each year there is a peak in migration, when ponds across called diving ducks. the state are crowded with waterfowl. While this period Diving ducks eat seeds and other parts of aquatic varies from year to year, it often follows heavy nighttime plants, fish, insects, mollusks, crustaceans and other in- rains in late March or early April. vertebrates. They dive underwater to obtain much of Diving ducks nest in New England, Canada, Midwest- their food. They have large broad feet, fully webbed and ern and prairie states, the Pacific Northwest and Alaska. with strongly lobed hind toes, that act as paddles. Their Several species inhabit both the Eastern and Western legs are spaced widely apart and located well back on hemispheres. Three species of mergansers (which, though the body, improving diving efficiency but limiting agil- not actually diving ducks, are usually grouped with them) ity on land. Their bodies are compact, and their wings breed in Pennsylvania's northern tier. have relatively small surface areas. While this arrange- Beginning in winter and before heading north, and into ment helps their diving and swimming, it hinders their spring, males in their brightly colored breeding plumage ability to become airborne. Instead of springing straight vie for females. Courtship may include ritualized drink- out of the water into flight, as puddle ducks do, diving ing and preening movements, posturing and calling. Copulation takes place in the water. Males and females form monogamous pairs that last until the female begins incubating eggs; then, the male leaves the area and usu- ally joins a band of other males. Nesting habits and habitats vary from species to spe- cies. Generally, female diving ducks lay 5 to 15 eggs in Ring-Necked Duck vegetation, tree cavities, or rock crevices over or near the water. Because females do not start incubating a clutch until they lay their last egg, young develop simul- taneously and all hatch at about the same time. Ducklings are covered with down, patterned with shades of yellow or brown to break up their body out- lines. Their eyes are open, and they can swim and feed themselves soon after hatching. The group, called a brood, remains together until the ducklings can fly, usu- ally 8 to 10 weeks after hatching. Adults undergo a post-breeding molt, growing a new set of feathers. Males molt first; in all species, the male's bright nuptial plumage is replaced by drabber, less-con- spicuous feathering. While their flight feathers are grow- ing, ducks cannot fly; they keep quiet and stay hidden during this period of vulnerability. Ducks are preyed upon by raccoons, foxes, mink,
40 1 - Canvasback, 2 - Redhead, 3 - Ring-Necked, 4 - Greater Scaup, 5 - Lesser Scaup, 6 - Today, waterfowl populations in the region are stable, Oldsquaw, 7 - Bufflehead, 8 - Hooded thanks to law enforcement and modern habitat manage- Merganser, 9 - Common Merganser, 10 - Red- ment and preservation. The U.S. Fish and Wildlife Ser- Breasted Merganser, 11 - Common Goldeneye, 12 - vice monitors waterfowl numbers. The service divides the United States into four administrative units called Black Scoter, 13 - Surf Scoter, 14 - White-Winged flyways (they correspond to four major migration corri- Scoter, 15 - Ruddy dors for waterfowl) and gives states within the flyways guidelines for setting hunting seasons and bag limits. Duck hunting is a challenging, rewarding sport. To hawks and owls; young are also taken by snapping turtles. pursue waterfowl, today's hunter is required to buy a fed- Crows, raccoons and skunks eat the eggs. eral duck stamp and a Pennsylvania migratory game bird In Pennsylvania, the fall migration of waterfowl be- license; revenues are used to monitor waterfowl popula- gins in late August, peaks in October, and ends in De- tions through surveys and to acquire wetland habitat. cember. Some ducks winter in our state, but most go far- Many people other than hunters also enjoy waterfowl, ther south. Diving ducks winter along the Atlantic and observing and photographing these colorful, diverse birds. Pacific coasts, across the southern states and in Mexico and Central America. Canvasback — Length, 20 to 21 inches; weight, 2½ Habitat is of prime importance to ducks. Wetlands to 2¾ pounds. Also called a "can." Plumage is black and originally covered some 127 million acres in the U.S., white; male has a red head, female, brown. Flight is swift but today more than half of those acres have been drained (up to 70 mph in calm skies, faster with a tail wind), with and converted to farmland, or developed for housing and little dipping and weaving; flocks number 5 to 30. industry. Drought periodically dries up parts of remain- Canvasbacks eat seeds and other parts of pondweeds, ing wetlands, affecting duck reproduction. Ducks are wild celery, eelgrass, widgeongrass, other aquatic plants, vulnerable to oil spills on coastlines where they winter mollusks and crustaceans. In Pennsylvania, the canvas- or breed. Pesticides, heavy metals and industrial pollu- back is an uncommon spring and fall migrant. It breeds tion also harm them, either directly or by killing food in the prairie states, Rocky Mountains, Canada and plants or animals. Alaska. In the Atlantic Flyway, wintering canvasbacks The Canadian prairie provinces — Manitoba, concentrating on the Chesapeake Bay comprise almost Saskatchewan and Alberta — form the single largest half of the entire North American population. Hazards breeding habitat for many duck species. Alaskan and on the breeding range include drought (the canvasback Canadian arctic wetlands are crucial to geese, swans and does not adapt as readily to drought-related habitat ducks. Our southern coastal states form an important changes as do other ducks); and loss of nesting habitat. wintering ground. The canvasback population, once greatly reduced by By the early 1900s, unregulated market killing had earlier market killing and consequently given periodic decimated duck populations along the Atlantic seaboard. closed-season protection, has rebounded and is hunted.
41 — Length, 19 to 20 inches; weight, 2 to 2½ Redhead the Great Lakes. The lesser scaup is the one normally seen pounds. Plumage is black and gray; male has a red head, in Pennsylvania. It frequents the larger bodies of inland female, brown. Flies in singles, pairs and in flocks of 5 to waters. Scaup eat mollusks, insects, crustaceans and 15. Redheads feed in shallower water than do other div- aquatic plants. Common spring and fall migrants through ing ducks, eating the seeds, tubers and leaves of plants, Pennsylvania, they breed across Canada into Alaska. They along with insect larvae and snails. In Pennsylvania, red- winter along the coasts. heads are uncommon migrants in spring and fall. They breed mainly in the northern United States and south- — Length, 16 to 20 inches; weight, 1¾ to 2 Oldsquaw western Canada, and winter across the southern United pounds. Also called a "long-tailed duck." Plumage, a strik- States and in Mexico. Females often lay eggs in the nests ing mix of black and white, shows much seasonal varia- of other ducks, and leave them to be incubated by the tion when found in the state. Food: crustaceans, mollusks, nest owners; they also desert their nests more readily than insects and fish. Oldsquaws may dive to 100 feet when do hens of other species. foraging. They are uncommon spring and fall migrants. Occasionally they winter in the state, but more often — Length 16 to 17 inches; weight, Ring-Necked Duck along the coasts and on the Great Lakes. They breed in 1¼ to 2 pounds. Also called a ''ring-bill." Plumage is black Canada, the Pacific Northwest and Alaska. and white for the male, brown and white for the female. The male has a faint brown ring around the neck (not — Length, 13 to 15 inches; weight, about Bufflehead easily seen in the field), and both sexes have a pale ring 1 pound. Also called a "butterball." Plumage is mostly near the tip of the bill. They fly swiftly in flocks of up to black and white on the male, and brown and white on the 20. They feed in shallow waters on seeds and vegetative female; the male has a large white patch on its head. Buffle- parts of pondweeds and other water plants, and on in- heads are fast fliers with rapid wing-beats. They eat sects, mollusks and other aquatic animals. Common mi- aquatic insects, snails, fish and other animal foods. Buffle- grants through Pennsylvania during spring and fall, ring- heads are common spring and fall migrants, breeding in necked ducks breed across southern Canada and the northern Canada and Alaska, and wintering along the northern United States. Some occasionally winter in Penn- coasts and in the southern states. sylvania, but most go to the coasts, the southern states and Mexico. Common Goldeneye — Length, 17 to 19 inches; weight, about 2 pounds. Also called a "whistler'' for the — These two nearly iden- Greater and Lesser Scaup sound of its wing-beats. Plumage is black and white on tical species are 16½ to 18 inches in length, and weigh the male, brown and white on the female. Goldeneyes dive 1½ to 2½ pounds. They are also called "broadbills" and for crustaceans, insects, mollusks and fish. Common spring "bluebills." Males are black and white, females, brownish and fall migrants, they breed across Canada and in Alaska, and white. The bill is blue for both species. Greater scaup and winter in Pennsylvania and across the continental inhabit large bays, sounds and inlets of both coasts, and United States.
42 range is farther north. Breeding habitat is heavy timber Ruddy Duck — Length, about 15 inches; weight, about around lakes, ponds, rivers and streams. Hooded and com- 1 pound. Small and stubby, the ruddy duck has a short, mon mergansers usually nest in tree cavities, while the thick neck, an upturned tail, and white cheek patches red-breasted nests on the ground, usually in thick cover. under a dark cap. It prefers to dive — rather than fly away Eggs: 6 to 17. Incubation is by the female and takes about — from danger. In flight, ruddy ducks skim low over the four weeks. Hooded and red-breasted mergansers winter water in compact flocks. Food is primarily vegetation along the coasts and in the southern United States: the (widgeon grass, pondweeds, bulrush seeds), midge larvae common merganser winters in Pennsylvania, on the Great and mollusks. Juveniles eat a larger proportion of energy- Lakes, and across the continent where the water remains rich animal food than do adults. Ruddy ducks are com- open. mon spring and fall migrants across Pennsylvania. They breed mainly in southwestern Canada, and winter along — Length, Black, Surf and White-Winged Scoters the United States coasts and in Mexico. 18½ to 22 inches; weight, 2 to 3½ pounds. All three sco- ter species are basically black, with varying amounts of — Hooded, Red-Breasted and Common Mergansers white in the plumage. These sea ducks fly in Hooded and red-breasted mergansers average 16 to 18 long, undulating lines, in irregular groups, inches in length, while the common merganser is 23 to 25 or in V-shaped flocks. They eat mollusks, inches. Weight, about 1½ pounds for the hooded and crustaceans, aquatic insects and plants. red-breasted, 2½ to 4 for the common. Mergansers They are rare to uncommon migrants over are known as "sawbills'' and "fish ducks." The Pennsylvania, passing through the state species have distinctive, colorful plumage. in March and April, and again in Octo- They fly fast and low over the water. ber and November. Scoters breed in Food: fish and their eggs and other Canada and Alaska. They winter on the aquatic animals. All three mergan- Great Lakes and along the Atlantic and ser species breed in Pennsylva- Pacific coasts. nia, although their principal Wildlife Notes are available from the Pennsylvania Game Commission Bureau of Information and Education Dept. MS, 2001 Elmerton Avenue Harrisburg, PA 17110-9797 www.pgc.state.pa.us An Equal Opportunity Employer
43 Wildlife Note — 18 LDR0103 Dove by Chuck Fergus In August, mourning doves seem to be everywhere: bond the pair and ward off other males. While females we see their slim, gray-brown forms on telephone lines, may coo in response, their calls are weak and scarcely in back yards, farm fields and weedy flats along highways. audible. Another distinctive sound identifies the mourn- By late September, their swift, direct flight takes them ing dove: a whistling produced by the wings of a bird in overhead on whistling wings. They flash south in bands flight. of 10 and 20, belly plumage catching the fading gold of Doves are beneficial to man; they eat seeds of pest late summer sunlight, and when the great masses of doves plants and generally do not damage crops. Foods are weed begin to depart, autumn is on its way. seeds and waste grains (these two items together may The mourning dove is a member of the family make up 98 percent of a dove's diet), a few insects, snails Columbidae and is closely related to the rock dove (do- and slugs. Doves don't cling to stalks or scratch for food; mestic pigeon). It breeds across all of the lower 48 states, they pick seeds off the ground. Favored weeds are cro- much of Mexico, the southern and western edges of ton, foxtail, smartweed, ragweed and seeds of various Canada, and into Alaska; it winters from Massachusetts, grasses and sedges. Grains eaten include corn, wheat, oats, southern Michigan, Nebraska and California south to barley, rye and buckwheat left on the ground by mechani- Panama. Colloquial names are turtle dove, wild pigeon cal harvesting methods. and wild dove. Seeds of plants such as croton and foxtail grass are very small, and single doves have been found with liter- Biology ally thousands (7,500 croton; 6,400 foxtail grass) in their crops. Grit aids in grinding up food, and it may be taken , weighs Zenaida macroura An adult mourning dove, in the form of gravel, cinders, glass or any other small, 3½ to 5 ounces and is 10 to 13 inches in length from hard material. Doves seen along roadsides are often pick- beak to tail tip. A dove is smaller and more streamlined ing up grit. In addition to food and grit, doves need wa- than a pigeon, with a long, pointed tail and tapering wings ter every day. Ordinarily they fly to a stream, creek or that spread 17 to 19 inches. The neck is long, the head pond early in the morning and again in the evening. small, and the bill slender, short and black. Small bands of doves begin to return to Pennsylvania A dove's wings are gray, and its back, rump and middle in early March, with arrivals peaking from mid-March tailfeathers are grayish olive-brown. The lateral through April. Some doves also winter in Pennsylvania. tailfeathers are bluish-gray, with black crossbars and Studies indicate that most birds returning to Pennsylva- white tips which flash when the bird is flying. The under- nia to breed have wintered along the southeastern coast sides of the body are pale buff; the head is buffy-brown — in North and South Carolina, Georgia and Florida. with a black spot behind the eye and pale, blue skin vis- The male selects a nesting territory and defends it by ible around the eye. Legs and feet are reddish. Both sexes flying at and pecking other males. He coos to attract a have similar plumage, although the male's colors are female and performs a nuptial flight in a large oval pat- somewhat brighter and more iridescent, especially the tern. The pair mate and select a nest site; together they head and breast. build a nest over the next 4 to 6 days, sometimes using a The species' call is distinctive, and earns the "mourn- vacant catbird, robin or grackle nest as a platform. Dove ing" half of this bird's name. The call is a hollow, plain- nests are built of sticks, with little if any lining material. ooah, cooo, coo, coo tive . Depending on distance, only Eggs may be visible from the ground through the loosely the last three notes may be audible. This call is made by woven twigs, but the nests are surprisingly strong for their males trying to attract females. After mating, it serves to frail appearance. They're built as high up as 50 feet (usu-
44 nesting habitat. Other ally 10 to 25 feet) in the crotch of a branch, typically in practices which de- conifers; or they may be constructed in tangles of shrubs crease the amount or or vines, or even on the ground. diversity of shrubs Two or three days after the nest is finished, the female and trees, how- lays her first egg. A second egg comes two days later, and ever, may affect incubation begins at once. (On rare occasions, a third doves ad- egg is laid.) Eggs are oval to elliptical, glossy, white and versely. To- unmarked. Incubation and brooding are shared; the male day, the dove sits on the eggs during the day, the female at night. After has the largest 14 to 15 days, eggs hatch. The nestlings, also called range of any squabs, are altricial: naked, blind and completely depen- game bird, al- dent on their parents. though breeding For the first few days, squabs are fed a mixture of small populations are appar- seeds and a nutritious liquid called "pigeon's milk," which ently decreasing slightly. is secreted by the dining of the adult's crop (the crop is The US Fish & Wildlife Service monitors dove breed- the upper portion of the digestive tract). This milk is a ing populations by conducting coo-count surveys. In chalky mixture of cells and fluid; both parents feed it to Pennsylvania, the dove population peaks in August and the young by regurgitation. Gradually, seeds begin to September when adults and locally produced young are compose the bulk of the developing squabs' diet. At 14 joined by migrants from farther north. They migrate lei- days, squabs are fully feathered, fledged and on their own surely, averaging about 15 miles per day. — and the adults are ready to produce another brood. As with any heavily preyed-upon species, the mourn- The nesting cycle — egg-laying, incubation and care ing dove has an extremely high reproductive rate (small, of squabs until they leave the nest — takes just more but multiple broods); in essence, parent doves don't put than a month. Adults make up to five nesting attempts all their eggs in the same basket. While dove numbers over the summer, finishing in August; about half of the fluctuate from year to year, there's no evidence that the nestings succeed, resulting in an average of 4 to 6 young population is cyclical. produced by each adult pair. Weather can be an important mortality factor. Spring Habitat and summer storms with high winds blow nests, eggs and young out of trees; heavy rains and hail may kill adults The mourning dove is a bird of open woodland edges. as well as nestlings. Nest predators include blue jays, star- Favored habitat includes farmland with scattered trees lings, crows, squirrels, snakes, house cats and others. and shrubs, open woods, evergreen stands, orchards, road- Adults are preyed on by hawks and owls. Disease, acci- side trees and suburban gardens. Doves usually avoid dents and hunting cut dove numbers further. dense forests. Life expectancy: 70 to 80 percent of all newly hatched Food isn't normally a limiting factor, because doves doves do not live one year (i.e., for every 100 hatched in can subsist on a tremendous variety of seeds and can fly a summer, only 20 to 30 will live to breed the following to places where food is adequate. Because they're so summer). If a juvenile survives its first year, the attrition mobile and adaptable, there's little need to manage habi- slows: adults have a 50 percent mortality rate. Average tat specifically for them. Shelterbelts can be planted for annual mortality for a stable population is estimated at nesting cover (red pine, long-leaf pine, Norway spruce 60 percent. and locust trees are suitable), benefiting doves and other Juveniles grow for and complete their feather devel- wildlife such as songbirds, pheasants, rabbits, etc. Also, opment in about two weeks after leaving the nest; then millet overseeded in corn provides extra food. they gather into small flocks to feed and roost. Migra- In general, doves concentrate in areas with plentiful tion of all ages is in full swing by mid-September or early weed seeds or waste grain, near trees for roosting and October. Flocks of a few to 20 or more birds travel to- nesting, and within easy flight of a water source. As long gether, flying in the morning, resting and feeding at noon, as such habitat exists — and right now it is abundant — flying in the afternoon, feeding in the evening, and roost- the mourning dove will continue to be one of our most ing at night. If the winter weather is not too severe, some plentiful and conspicuous wild animals. birds spend the entire year in Pennsylvania. Because the mourning dove is a migratory bird, it falls under federal regulations. As with waterfowl, the states set hunting seasons and bag limits within a framework determined by the US Fish and Wildlife Service. Doves have been hunted in Pennsylvania since 1945. Wildlife Notes are available from the Pennsylvania Game Commission Population Bureau of Information and Education Dept. MS, 2001 Elmerton Avenue Mourning doves adapt well to man and his activities. Harrisburg, PA 17110-9797 In the last 200 years, the dove population has increased www.pgc.state.pa.us greatly — probably as a result of intensified agriculture and expanding suburbs which provide much shrubby An Equal Opportunity Employer
45 Wildlife Note — 32 LDR0603 Eagles and Osprey by Chuck Fergus Large, striking birds of prey, the bald eagle, golden Eagles feed mainly on fish (60 to 90 percent of their eagle and osprey seem to embody power and majesty. All diet) either living or as carrion. They also eat birds and three occur in Pennsylvania, although none are common small mammals. Eagles soar above the water or sit on a here. On a continental scale, human encroachment on convenient perch; when they spot a fish near the water's habitat and environmental contamination reduced the surface, they swoop down and snatch it in their talons. birds' numbers and lowered their breeding success. The They use their talons for killing, and their heavy bills for Pennsylvania Game Commission, along with many other tearing apart prey for eating. Sometimes an eagle will go states, has been working to reverse that trend since the after an osprey, forcing it to drop a captured fish, which 1980s, and as a result, the birds are much more common the eagle grabs in midair. now than they were in the 1960s, '70s and '80s. Eagles mate for life, although when one partner dies, Taxonomists place bald and golden eagles with the the other readily finds a new mate. Nesting is preceded buteos — hawks with broad wings and broad, rounded by a spectacular aerial courtship, with the birds locking tails. Other Pennsylvania buteos are the broad-winged, talons, diving and somersaulting in the sky. red-tailed, rough-legged and red-shouldered hawks. The An eagle's nest is called an eyrie. The big raptors osprey is the only species that's a member of the family choose large, sturdy trees. Nest sites are near lakes, riv- Pandionidae. ers, reservoirs and seashores. ( Haliaeetus leucocephalus) — The bald Bald Eagle eagle's taxonomic name means "white-headed sea eagle." The word "bald" is a misnomer. The mature eagle's head is covered with gleaming white feathers. Its body is dark brown, its tail white. Immatures are brown, mottled with white on their wings and body. Full adult plumage is at- tained in the fifth year. Both adults and immatures have yellow bills and feet; legs are feathered halfway down. Eagles were listed as a federally endangered species until 1995, when their status was upgraded to "threat- ened." In Pennsylvania, they remain a state endangered species. Adults are 30 to 40 inches in length and weigh 8 to 14 pounds. Wingspan is 6 to 8 feet; standing height, about two feet. As with other birds of prey, the female is larger than the male. Bald eagles fly with strong, deep strokes, or soar on flattened wings. Their eyesight is among the keenest in the animal world, five or six times sharper than a human's. An eagle's call is a rapid, harsh cackle, kweek-kik-ik-ik- Bald Eagle kak-kokkak ik-ik , or a lower .
46 Adult Immature Osprey Bald Eagle A new nest is about five feet wide and two feet high, 1990, new bald eagle nests have been found. By 1996, with an inside depression 4 to 5 inches deep and 20 inches the state's nesting eagle population had climbed to 20 in diameter. Often a pair returns to the same nest year pairs. Six years later, eagles were nesting in at least 22 of after year, adding a new layer of sticks, branches and corn- Pennsylvania's 67 counties. stalks, plus a lining of grass, moss, twigs and weeds. En- In winter, an occasional eagle may turn up almost any- larged annually, some nests grow so big and heavy that where in Pennsylvania. Three popular wintering areas are they break the branches supporting them. Pymatuning; the upper Delaware River (primarily in the The female lays two eggs (sometimes only one and Pike County area); and the lower Susquehanna, between occasionally three) in March or April. Eggs are about Lancaster and York counties. Wintering birds may form 2¾ by 2½ inches, dull white and unmarked. Both par- loose groups, or wander as individuals. Younger birds are ents incubate. If all goes well, the eggs hatch after about more inclined to wander. 35 days. Young birds (eaglets) are fed by their parents. A Bald eagles can live 30 years or longer in the wild. large, healthy hatchling may kill a smaller, weaker one. They have few natural enemies. Some are killed by Eaglets develop most of their feathers by 3 to 4 weeks, thoughtless humans, and others are electrocuted when walk in the nest at 6 to 7 weeks, and begin to fly at about they land on power lines. three months. Young separate from their parents in au- An estimated 50 percent of eaglets survive their first tumn. year. Factors depressing reproduction are many. If hu- Eagles are uncommon in Pennsylvania, although they mans intrude on the nest area, eagles may abandon eggs may show up here in all seasons. In spring, they migrate or leave young vulnerable to severe weather or preda- north to nest in April, with stragglers into May. August tors. Eagles do not breed until 4 or 5 years of age. Their and September find eagles returning south, with most natural reproduction rate is slow. Breeding habitat — heading for Florida to winter. Pennsylvania's eagles seem tall, sturdy trees near bodies of water in remote areas — to spend much of the winter near their nesting areas; ap- is dwindling. Toxic chemicals introduced into the envi- parently they do not migrate. ronment cause repeated nest failures (see "Raptor Re- There were only three known bald eagle nests in Penn- production" section at the end of this Note). sylvania from 1963 through 1980, all in the Pymatuning/ The bald eagle was chosen the United States' national Conneaut Marsh region in the northwestern part of the symbol in 1782. At that time, an estimated 25,000 lived state. From 1983-89, the Game Commission removed 88 in what is now the lower 48 states. Today the same area eaglets from nests in Saskatchewan, and raised and re- probably supports 4,000 breeding pairs, mostly in the leased them through hacking. Hacking is a falconer's term South, the West and the Pacific Northwest. Fairly large for maintaining a young bird in a semi-wild condition, populations still inhabit northwestern Canada and providing food until it can fend for itself. Every year since Alaska.
47 October; some also pass through in April and May. They do not breed in our state, although individuals Adult are sometimes sighted in summer. Some occasionally winter here in rugged, remote terrain. Most goldens breed across cen- tral Canada, in the western United States, Alaska and Mexico. In the Northeast, active nest sites have been reported in New York, New England and Quebec. Breeding habits are similar to those of bald eagles, except goldens often locate their nests on cliffs. After fledging, young remain in the nest area during summer, then wan- der away from the site with their Immature parents. They do not breed until five years of age. Estimates place the North American population at anywhere from 8,000 to 50,000. The golden eagle is not on the federal threat- ened or endangered list, but has dis- appeared from most of the northeast- Golden Eagle ern states. The osprey is a Pandion haliaetus) — ( Osprey large, eagle-like hawk found throughout North America and in the Eastern Hemisphere. It inhabits seacoasts and (Note: Persons wanting to see an eagle nest may do so the areas near large rivers and lakes. In Pennsylvania, it from the Pennsylvania Game Commission's Pymatuning shows up along the Susquehanna and Delaware rivers, and Waterfowl Museum, just south of Linesville. Eagles have near creeks, ponds, lakes and reservoirs throughout the been maintaining a nest on Pymatuning Lake's Ford Is- state, depending on the season. land for some time. The best time to watch is from early Plumage is dark above, white below. Adults and juve- March to mid-May, before trees leaf out. Spotting scopes niles are colored alike. The head is largely white, with a or binoculars are necessary.) black patch across each cheek. A conspicuous crook to the wings and black "wrist" marks are good field identifi- Golden Eagle — The golden eagle Aquila chrysoetos) ( ers. is a magnificent predator of remote, mountainous areas. Except when migrating, ospreys flap more than they The species occurs in Eurasia, North Africa and North sail. Wingbeats are slow and deep. Ospreys hover 50 to America, where it's most common in the western United 150 feet up and then plunge to the water for their fish States, Canada and Alaska. The golden eagle is rare in prey, sometimes going all the way under. the Northeast. Ospreys are 21 to 24 inches from bill to tail. Their Adults and immatures have rich, dark-brown body wings span 4½ to 6 feet. Standing height is about 1½ feet. plumage, with gold-tipped feathers on the head and neck. , etc. cheep, cheep Their call is a series of loud whistles, The legs are feathered to the toes. Adults resemble im- In spring, ospreys migrate through Pennsylvania in mature bald eagles, but the goldens are darker. Immature April and May. Several hundred individuals summer here. goldens have white wing patches and, for their first sev- Fall finds these so-called fish-hawks heading south along eral years, a broad, white band at the base of the tail. the mountain ridges in August, September and October. Golden eagles are classic buteos, with long, rounded Most winter in South America's Amazon River region. wings. They flap less and soar more than bald eagles. Body Like eagles, ospreys build bulky nests of sticks and length is 30 to 40 inches; wingspan, 6½ to 7½ feet; stand- twigs, lined with inner bark, sod or grasses. Sometimes ing height, about two feet. Their call is a series of rapid, they add debris (rope, fish net fragments, cans, seashells, sharp chirps. etc.). Nests are in living or dead trees, on the ground, or Prey includes small rodents, hares, rabbits, birds, rep- on man-made structures — utility poles, fishing shacks, tiles and fish. Goldens crush prey in their sharp talons, billboards, channel buoys, chimneys and the like. Often and use their large, hooked beaks to rip it apart for eat- added to and used year after year, the nests can become ing. In the West, these fierce, powerful predators have huge. been known to knock young mountain sheep and goats Eggs: three, sometimes two, and rarely four; 2¼ by 1¾ off high ledges, then feast on the remains below. inches; white or pinkish-white with brown spots and In Pennsylvania, golden eagles are regular migrants in
48 cals remain in our natural food chains because they do blotches. The female incubates 32 to 33 days, and young not break down rapidly. Still, it appears the alarming de- leave the nest when 51 to 59 days old. Dr. Larry Rymon of East Stroudsburg University in 1980 cline in raptor reproduction in the 1960s and '70s has began reintroducing ospreys to the state's northeastern leveled off, perhaps indicating some progress toward cleaning up the environment, or at least stabilizing present counties. The first Pennsylvania-hacked osprey returned in 1983, and two years later the state documented its first pollution levels, has been made. nesting pair since 1910. By 1996 more than 260 ospreys had been hacked in the state. In 1996, Pennsylvania had How You Can Help 26 nesting pairs. An osprey has strong ties to the area where it was born, and usually returns there to breed. Wildlife biologists are always looking for information about eagles and ospreys. If you find a bald eagle or osprey Raptor Reproduction nest, report it to your local Wildlife Conservation Of- ficer or Game Commission region office. Be careful not to disturb the birds. Reproductive failure is a problem for bald eagles and ospreys. Much of the problem stems from man's use of If you find an injured eagle or osprey or hear of one, call the Game Commission. Injured birds can often be now-banned toxic chemicals. DDT, dieldrin, and other treated and rehabilitated. chlorinated hydrocarbons sprayed to kill in- Eagles, ospreys and other birds of prey sects, drain into rivers and get into fish. Bald are protected by federal and state laws. eagles and ospreys eat a lot of fish, and ac- Report any violations. cumulate the chemicals in their bodies. Educate others about eagles and Other pollutants such as PCBs and heavy metals may also affect their ospreys. Some people still believe reproduction. these priceless natural treasures The chemicals cause birds to are detrimental to game and fish lay infertile or thin-shelled populations. They are not. eggs, which break under the Contribute to the Game Commission's "Working To- weight of an incubating bird. Although environmental regu- gether for Wildlife" fund, and to private wildlife organizations lations have banned the use of "hard" pesticides, the chemi- and raptor rehabilitation cen- Osprey ters. Foot Wildlife Notes are available from the Pennsylvania Game Commission Bureau of Information and Education Dept. MS, 2001 Elmerton Avenue Harrisburg, PA 17110-9797 www.pgc.state.pa.us An Equal Opportunity Employer
49 Wildlife Note — 39 LDR0603 Coyote by Arnold Hayden The eastern coyote has stirred as much interest and lently turned in as wolves here during the late 1800s. emotion as any other animal in Pennsylvania. Seeing a Little is known of the wolf in Pennsylvania, or if in- coyote or hearing the howl of this wild, wily animal is a deed the same animal now called the "eastern coyote" great reward of nature to many people. Others fear this may in fact have been similar to the wolf of the past. animal just knowing it is in the wild. Some sportsmen Pictures dating to the 1930s have appeared in Game News hate coyotes because they think the predators kill too the years. These animals look like the same coyotes over many game animals. Trappers and hunters find coyotes being killed today. The first coyote identified as an ani- to be especially challenging. Some farmers lose livestock mal similar to what we today call the "Eastern coyote" due to coyote predation. The coyote has been referred was killed in Tioga County in 1940. to as the brush wolf, prairie wolf, coy-dog and eastern In the late 1960s, it appears an influx of coyotes en- coyote. tered northern Pennsylvania from the Catskill Mountains (Canis latrans) is found through- The eastern coyote in New York, and from there they spread south and west out northeastern United States and southeastern Canada. across the state. In the 1970s, the highest population was Recent research shows the eastern coyote is an immi- in the Pocono Mountains of the state. The coyote con- grant whose origin may have involved interbreeding be- tinued to expand its range during the late 1970s and oc- tween coyotes and gray wolves. Analysis of DNA sug- cupied the entire state by 1990, with the highest popu- gests coyote/wolf hybridization has occurred. Other stud- lations across the northern half of the state. ies indicate that the eastern coyote is intermediate in size and shape between gray wolves and western coyotes. Biology As a result, the eastern coyote exhibits different behav- ior, habitat use, pelt coloration, prey preferences and The eastern coyote is much larger than its western home range sizes from its western cousin. The eastern counterpart. Adult males in Pennsylvania weigh 45 to coyote is the largest canine found in Pennsylvania. The 55 pounds. The heaviest known male caught here following information pertains to the coyote in Pennsyl- weighed 62 pounds. Females are smaller, 35 to 40 pounds. vania and throughout northeastern United States. The heaviest known female in Pennsylvania weighed 42 pounds. Total body length of eastern coyotes ranges from History 48 to 60 inches. Their pelage colors range from light blond, reddish blond, gray to dark brown washed with Fossil records indicate coyotes have existed in what black, and black. Generally, coyotes are gray to a Ger- is today eastern North America since the Pleistocene pe- man shepherd coloration. Their legs are gray, tan and riod, a million years ago. Occurrence has been intermit- reddish with black markings or lines down the front of tent over that time, and only in the front legs. The cheeks and behind the ears the past 75 to 100 years has are reddish or chestnut colored. Blond, the animal appeared to be- reddish and black coyotes may not come common. The coy- have any noticeable black ote status in Pennsylvania stripes on their front legs. during the 1700s and Their ears are erect and 1800s is clouded with their bottle brush tail is that of the wolf. Old usually held in a down- bounty records indicate ward position. Normally, both coyotes and wolves their eyes are yellow, but from other sections of some with brown eyes the country were fraudu- have been found.
50 populated areas of Philadelphia, Harrisburg, Pittsburgh Coyotes are monogamous; they maintain pair bonds and Erie. Coyotes prefer heavy brushy cover, such as for several years. The social unit evolves around the clearcuts, and often live along edges between forest and mated pair and its offspring. However, the delayed dis- agricultural areas where prey is abundant. persal of some offspring may result in extended family relationships beyond a year. A social group occupying a Food Habits territory may include a pair of adults (generally more than a year old), transients (aged 6 to 18 months), pre- The coyote is a generalist. An analysis of 300 coyote dispersing sub-adults (usually less than a year old) and scats collected in Pennsylvania indicate a wide array of non-breeding associates that are more than one year old. food items in their diet. Mammals from at least 13 gen- Observations indicate other coyotes living in a territory may help provide food to a growing litter. era were found, ranging from small mice and voles to deer. Normally, females do not breed — or implant em- Overall, deer was the dominant food, occurring in 57 bryos — until their second winter, but there are percent of the scats. That deer were a dominant cases of some yearling females breeding and pro- food item was not surprising given the high deer ducing litters. They have one heat period that density in many areas, the large number of deer killed on the highways, starvation lasts 4 to 5 days, usually in February. The litters are born from mid-April to early May, losses, and deer that have died for any num- and litter sizes average 5 to 7 pups. Coy- ber of other reasons. otes compensate for unusually high mor- Rabbits and woodchucks ranked behind small mammals and deer as important food tality by having larger litters. Known den- items. Birds were found in 10 percent of the ning sites range from beneath over- turned trees, piles of tree stumps, rock scats and insects in 18 percent. Plant ma- dens, and dug out red fox dens. Dens are terial occurred in 50 percent of the scats. Various kinds of fruits were important dur- usually located on southerly exposures. The pups are moved frequently to new ing the late summer and fall, but plant ma- dens to avoid detection. terial appeared important on a year-round basis. While no livestock was found in the Young coyotes begin to disperse from analysis, predation on sheep, chickens, the family group during October, when they're six months old. Studies in Penn- ducks, goats and domestic rabbits does oc- sylvania indicate some juvenile coyotes cur, but at a low rate. However, depredation can be significant in localized areas or at cer- dispersed up to 100 miles, but 30 to 50 tain farms. miles is more common. Coyotes use a variety of yips, barks Population and howls to communicate and periodically assemble into larger packs. Coyotes at times will Coyotes are found throughout Pennsylvania, but are "pack" and at other times will hunt alone or in the com- most common in the northern half. The total population pany of another coyote or two. They are primarily noc- in 1995 was probably between 15,000 to 20,000. The turnal, but often hunt during daylight hours, especially harvest in the early '90s exceeded 6,000; incidental to in the morning. Howling may occur at any time of day, turkey, bear and deer hunting. Coyote hunters and trap- but the highest activity is usually at night. A coyote's pers accounted for the other half. Mortality from hunt- sense of smell, hearing and alertness are especially keen. ing and trapping approaches 60 percent for young coy- otes, but only 15 percent for adults. Habitat Coyote populations throughout North America have continued to expand, despite man's attempt to control The coyote has adapted to a wide variety of habitats them. If there's one thing we have learned about this in- in Pennsylvania. The animals can be found in the heavily triguing animal, it's that the coyote controls its own des- forested northeast and northcentral regions of the state, tiny, not man. in dairy and cropland areas, and even around the heavily Wildlife Notes are available from the Pennsylvania Game Commission Bureau of Information and Education Dept. MS, 2001 Elmerton Avenue Harrisburg, PA 17110-9797 www.pgc.state.pa.us An Equal Opportunity Employer
51 Wildlife Note — 33 LDR0103 Elk by Chuck Fergus Before white settlers arrived in Pennsylvania, the East- Elk have a summer and a winter coat. The summer lived throughout the state, with ern elk (Cervus elaphus) pelage is short, thin and reddish brown. In winter, long, concentrations in the northcentral and Pocono moun- coarse guard hairs overlay wooly underfur. At this time, tains. By 1867 the species had been extirpated; ultimately an elk's body is tawny brown or brownish gray, with the it became extinct throughout its range, which included neck, chest and legs dark brown, and the underparts New York and New England. darker than the back. Buffy or whitish fur covers the rump Today, elk inhabit portions of Elk and Cameron coun- and the 4-5 inch tail. Sexes are colored essentially alike. ties, and are being seen more and more in Clinton and Young elk, called calves, are dappled with spots. Clearfield counties. The animals are descendants of Strong muscular animals, elk can run 30 miles per hour (Cervus elaphus nelsoni, a closely Rocky Mountain elk for short distances, and can trot for miles. They jump related subspecies) released by the Pennsylvania Game well and swim readily. Their senses of smell and hearing Commission between 1913 and 1926. are keen. The word "elk"comes from the German "elch," the Cow elk often bark and grunt to communicate with name for the European moose. The elk is also called their calves, and calves make a sharp squealing sound. "wapiti," an Indian word meaning "white deer,'' probably The best known elk call, however, is the bull's bugling. referring to the animal's sun-bleached spring coat or its Bugling occurs primarily during the mating season. It light-colored rump. consists of a low bellow that ascends to a high note, which The elk is the second largest member of the deer fam- is held until the animal runs out of breath, followed by ily in North America; only the moose is larger. Many guttural grunts. Cows also bugle at times. Western states and several Canadian provinces support Each year, a bull grows large branching antlers that thriving elk populations, and in those places the elk is a sweep up and back from the head. In May, two bumps popular big game animal. start to swell on the animal's skull, pushing up about half an inch per day. The growing antlers are covered with a Biology soft skin called velvet. This covering contains blood ves- sels which supply growth materials to the enlarging ant- Elk are much larger and heavier than white-tailed deer. lers. A mature male elk, called a bull, stands 50-60 inches at Yearlings usually grow single spikes 10-24 inches in the shoulder and weighs 600-1000 pounds. Females, or length, while older bulls may produce racks with main cows, weigh 500-600 pounds. beams 4-5 feet in length and having 5, 6 or, rarely, 7 tines to a side. An elk with a total of 12 antler points is called a ''royal" bull; one with 14 points is an "imperial." Be- fore the autumn rutting season, the velvet dries and is shed or rubbed off. Bulls carry their antlers into late win- ter or early spring. Elk are primarily grazers, eating a variety of grasses and forbes. In winter, they paw through snow to reach grass, or turn to twigs, buds and the bark of trees. Among trees and shrubs, Pennsylvania elk seem to prefer aspen, red maple, fire cherry and blackberry. They also browse
52 host — which they inadvertently consume while grazing. The worm eventually reaches the brain and spinal col- umn, causing death. Habitat Elk are attracted to forest clearcuts, revegetated strip mines, grassy meadows, open stream bottoms and agri- cultural lands. Shy animals, they tend to avoid contact with humans, although they will venture into settled ar- eas to reach favored food sources. Pennsylvania's elk live in Cameron, Clearfield, Clinton, Elk and Potter counties, in the state's northcentral region. The elk range covers about 835 square miles. The Game Commission and state Department of Con- servation and Natural Resources (DCNR) are managing public lands to make them more attractive to elk. The agencies create and maintain high quality foraging areas and limit disturbance by humans. Elk habitat enhance- oak, striped maple, black cherry, Juneberry and witch ment projects also benefit deer, wild turkeys, grouse and hazel. They drink from streams and springs and, if neces- other wildlife. sary, during the winter they get water by eating snow. Population The mating season is September and October. Bulls bugle invitations to cows and challenges to other bulls. From 1913 to 1926 the Game Commission released a The bulls fight with each other, joining antlers and push- total of 177 elk in Blair, Cameron, Carbon, Centre, ing and shoving. Battles rarely end in serious injury; the Clearfield, Clinton, Elk, Forest, Monroe and Potter coun- weaker bull usually breaks off the confrontation and trots ties. From 1923 to 1931, the Commission opened a hunt- away. ing season on antlered bulls, and hunters took 98. Like their western counterparts, Pennsylvania bull elk By 1940, the released elk and their offspring died or amass harems of 15-20 cows. Most harems are controlled were killed everywhere in the state except for those in by large mature bulls, although younger males, which Elk and Cameron counties, which was, interestingly, the hang around on the fringes of the groups, may also share area where last native elk was killed. In 1971, when the in the breeding. Game Commission and DCNR began what became an- About 8½ months after she is bred, a cow gives birth nual elk surveys, 65 were counted by ground and aerial to a single calf — rarely twins — in May and June. A calf spotters. By 1980, the number of elk counted rose to 114. weighs about 30 pounds and can stand when only 20 min- In 1992, the ground spotters were eliminated from the utes old. Within an hour it starts to nurse, and it begins survey and the herd was estimated to number 183. In feeding on vegetation when less than a month old. 2001, survey work indicated the herd contained more In spring and summer, bulls go off by themselves, liv- than 700 elk. That same year, the Game Commission, ing alone or in small groups. Cows and calves tend to once again, had an open, but closely regulated hunting remain in family units composed of a mature cow, her season. calf and immature offspring from the year before. Some- The Game Commission and DCNR continue to con- times several families band together. An old cow will lead duct annual population surveys and perform habitat im- the group, barking out alarm calls and guiding the band provement projects on state lands. The Rocky Moun- away from intruders. In hot weather, elk bed down in the tain Elk Foundation has also played a major role in help- shade of dense timber. They prefer not to move about in ing to improve Pennsylvania's elk management program heavy wind. by making large monetary contributions. These funds Potential lifespan for an elk is 20 years. Pennsylvania have been used to help buy important land on the pri- elk die from old age, disease, vehicle collisions and poach- mary elk range, erect deterrent fencing, improve habitat ing. and construct an elk viewing area on SGL 311 near Parelapho- Brainworm is a parasitic nematode ( Benezette. Other organiza- ) that some- strongylus tenuis tions contributing to the elk times kills Pennsylvania elk. management program in- The nematode is common Wildlife Notes are available from the clude the National Wild in the eastern United States Pennsylvania Game Commission Turkey Federation, Safari and Canada. Its primary Bureau of Information and Education Club International, Con- host is the white-tailed Dept. MS, 2001 Elmerton Avenue solidated Natural Gas deer, which it does not nor- Harrisburg, PA 17110-9797 Transmission and Pennsyl- mally harm. Elk pick up the www.pgc.state.pa.us vania Wildlife Habitat Un- parasite from snails — an limited. intermediate brainworm An Equal Opportunity Employer
53 Wildlife Note — 60 LDR0103 Finches in Undulating Flight Finches and House Sparrow by Chuck Fergus Finches are small to medium-size songbirds with mixed and open woods. In winter they eat weed, grass sturdy bills that let them crack open the tough hulls of and tree seeds (elm, ash, sycamore and tulip tree); in early seeds, their main food. Five species breed in Pennsylva- spring they consume buds and flowers of trees and shrubs; nia; one, the house finch, is a western species liberated they take some insects in late spring; and they feed on in the Northeast that has become quite common. Finches fruits in summer. are sociable birds, and outside of the breeding season The male has a melodious warbling song. The female they gather in flocks. They feed on the ground and in tall builds a nest 15 to 20 feet above the ground, on a hori- weeds, shrubs and trees. Even during summer, when in- zontal branch, usually in a conifer; she weaves a com- sect populations burgeon, many finches continue to eat pact open cup out of twigs, weeds, rootlets and strips of seeds and even nourish their young with a pulp composed bark, and lines it with fine grasses or animal hair. The of regurgitated seeds. In winter, many of the birds in this three to five eggs are a pale greenish blue, dotted with group frequent our bird feeders. black and brown. The female incubates them for around Male finches sing to attract females and to maintain 13 days. Both parents feed the nestlings, mainly with seeds, pair bonds. In most species the female builds a cup-shape and they fledge about two weeks after hatching. In the nest hidden in the thick foliage of a tree or shrub. Fe- East, only one brood is raised per year. In winter, purple male finches do most or all of the incubating, and males finches may join foraging flocks and females team up to feed the young. with American goldfinches, pine House siskins and other species. At Finch Carpodacus purpureus Purple Finch ) — Don't look ( feeding stations, house finches for a purple bird when trying to pick out this species: and house sparrows dominate The male purple finch is maroon-red, while the female is purple finches and often drive brown with darker streaks. The spe- them away. Purple finches winter cies breeds across Canada and in as far south as Florida. the Northeast south to West Virginia. In Pennsylvania, House Finch ( Carpodacus purple finches nest mainly mexicanus ) — House finches in the northern tier, and in the eastern United States in winter, individuals are descendents of birds re- from farther north over- leased in New York City in spread the state. 1940. The species is native to Purple finches inhabit the US Southwest; today conifer plantations Carpodacus mexicanus breeds Purple Finch (including Christ- from coast to coast. Females mas tree farms), are sparrowlike, and males spruce bogs, hill- are similar to male purple side pastures, finches, except that house finches woods edges and show more streaking on the breast, are
54 hatched, although not quite as robust, and are a more bright red. The red they remain in pigment in both species comes from beta-carotene found flocks and do not set in many plants, particularly in red fruits; the red blush to up territories until the plumage intensifies as males age. House finches live late June or early in cities, suburbs and farms. They feed on seeds, flowers, July. In the buds, berries, small fruits and a few insects. spring, gold- Pairs often form within flocks during winter. Males do finches eat not stake out territories but, instead, defend areas around American seeds, in- their mates. House finches begin nesting as early as March sects and in- and produce two or more broods per year, each with four Goldfinch sect eggs. In or five young. Females nest in a variety of sites including summer they turn conifers, ivy on building walls, abandoned nests of other mainly to the seeds of thistles, dandelions, ragweeds, sun- birds, above porch lamps and in hanging flower baskets. flowers and grasses. They eat elm seeds, birch and alder The population of this western species "exploded" until catkins, flower buds and berries. They clamber around around the mid-1990s, when an eye disease seemed to in weeds and shrubs, picking out seeds. In winter, flocks have curbed the growth in the East. may seem to roll across a field, as birds in the rear leap- frog over other flock members on the group's leading Pine Siskin ( Carduelis pinus ) — With their brown col- edge: this strategy gives each individual access to fresh ors and streaked breasts, pine siskins look like sparrows; foraging areas while requiring only short flights to get patches of yellow in the wings and tails are good field there. identifiers. Pine siskins nest in New England and Canada Goldfinches start nesting later in the season than any and in scattered sites southward in the Allegheny Moun- other bird in the Northeast; perhaps breeding occurs late tains. In Pennsylvania they breed mainly in the northern so that young hatch when seeds mature on favored tier, nesting in stands of hemlocks, pines, food plants, particularly thistles. Flocks break up spruces and larches, and in ornamental as males claim territories, in loose colonies, up conifers in backyards. These tame birds to a quarter-acre in size. The male sings become much more visible when they from a perch, voicing a clear canary- flock to feeding stations in winter. like song, and makes high, circling As well as eating seeds put out by flights. The female builds a neat cup people, siskins consume the lined with thistle or cattail down, 4 seeds of trees (alder, to 14 feet up in a horizontal or up- birch, spruce and right fork of a small tree or shrub. others), weeds and Goldfinches often nest in grasses. They also thornapples, shrub willows and eat buds, flower gray dogwood clumps. The nest is parts and some in- woven so tightly that it will hold water; sects. They usually for- flexible, it expands as the young increase in age in flocks, even dur- size. The female lays four to six pale bluish ing the nesting season; in eggs. She incubates the clutch, with the male winter they're often seen bringing her food. The young hatch after 12 to in the company of gold- Pine Siskin 14 days, are fed mainly on seeds by their par- finches. In some years ents, and leave the nest after another 11 to 17 days. many siskins winter in the Some pairs raise a second brood, and fledglings have Keystone State, and in other been found as late as September. Cowbirds sometimes years few show up. parasitize goldfinches, but the young cowbirds often die because they don't get enough protein from the regurgi- American Goldfinch ( Carduelis tristis ) — The male tated seeds that goldfinch parents feed to nestlings. goldfinch in summer is one of our most conspicuous birds: bright yellow, with black wings and a black forehead. The Passer domesticus ) — Although ( House Sparrow female is a dull olive-gray. In winter both sexes look like named a "sparrow," this ubiquitous bird is actually a the summer female. Goldfinches are gregarious and are member of the weaver family, a large group of Old World often seen flying in groups, in a characteristic bouncing birds. House sparrows have spread from Eurasia, and can or undulating flight pattern: bursts of wingbeats followed now be found living with humankind around the globe. by short glides when the birds lose a few feet of height. People introduced them in North America between 1850 perchickory While airborne, flock members sound a call. and 1886 in an attempt to control insect pests, particu- American goldfinches nest across North America and larly the elm spanworm caterpillar. At first the bird was statewide in Pennsylvania. They forage in a variety of called the "English sparrow," because most imports were habitats including brushy areas, roadsides, open woods, brought from England. Male house sparrows have black woods edges and suburbs. chin and breast patches (the amount of black varies American goldfinches are with us year-round. Some among individuals), white cheeks and a chestnut nape. winter in Pennsylvania; others move in from the south in Females are a dingy brown. April and May, returning to breed in areas where they
55 House sparrows live year- Loxia Red crossbills ( round on most of the species' curvirostra ) and continent-wide range. Never white-winged far from humanity, they in- crossbills ( Loxia habit cities, suburbs, towns ) have leucoptera and farms. They eat weed oddly shaped bills, and grass seeds, waste the tips of whose grains, chicken feed, in- mandibles cross. A sects and spiders (about bird will stick its bill ten percent of the diet), between the scales of fruit tree buds, flow- a spruce cone, then ers, crumbs and gar- open the mandibles, pry- bage. They nest in ing apart the scales; the bird protected places, lifts out the exposed seed with including holes its tongue. The male red cross- in trees and bill is brick red in color, and buildings, the female is a mix of olive-gray Red Poll porch and and yellow. The white-winged crossbill has white wingbars in both sexes; the male is a rosy pink, and the female is colored much like the red crossbill female. Both types of crossbills eat the seeds of various conifers, and they also feed on buds and weed seeds. In House the years when they winter in Pennsylvania, they may Sparrows arrive with cold fronts in late October and November. ) has a red The common redpoll ( Carduelis flammea barn rafters, behind shutters and awnings, in bluebird forehead and a black chin. It is the size of a goldfinch. houses, and in thick growth of ivy on the sides of build- Redpolls feed actively in brushy and weedy fields and ings. Often they destroy the eggs and young of native cav- along woods edges, picking up seeds of trees, weeds and ity nesters. House sparrows use their nests for shelter dur- grasses. Often they forage in mixed flocks with pine siskins ing most of the year. Both sexes work at lining the cavity and goldfinches. with grass, weeds, feathers and trash. Pairs are monoga- ) is a Coccothraustes vespertinus The evening grosbeak ( mous; prolific breeders, they produce two or three broods big, husky bird. The male is dull yellow with prominent of three to seven young annually. Recently-fledged juve- white wing patches, and the female is yellowish gray; the niles form flocks in summer and are joined by adults after massive bill is white in both sexes. Wintering flocks wan- the breeding season ends in August and September. In der widely in search of food, although a feeding station late fall, pairs return to their nest cavities. frequently restocked with sunflower seeds will hold them When house sparrows overran the United States in the in one area. Evening grosbeaks forage in mixed wood- th early 20 lands, coniferous forests, towns and suburbs. At bird feed- century — ousting native breeders, fouling ers, they often displace one another, as well as the local buildings with their droppings, and offending people with birds, giving strident chirping calls and putting on ag- their aggressive, noisy habits — those who had champi- gressive displays while competing for food. oned the species' introduction were roundly castigated. th century. Since The population peaked in the early 20 then, it has fallen. Several factors may be involved. Trac- tors and automobiles have replaced horses, and farming operations have been sanitized, so that grain is no longer widely available in winter. Winter Finches — In addition to our five breeding species, four Red Crossbill other finches breed in the far north and visit the Northeast in winter, when they may descend on feeding sta- tions in peoples' yards. In some years many finches in- vade our area; in other years they stay in the north. Ornithologists believe that finches come south when key food sources, particularly the seeds of conifers, fail in their bo- real habitat. Evening Grosbeaks
57 Wildlife Note — 40 LDR0103 Fisher by Tom Serfass & Denise Mitcheltree , are swift and elegant tree- Fishers, Martes pennanti achieve sexual maturity until their second year. Breed- climbing furbearers. Like the river otter, mink, skunk and ing occurs in the spring and the overall gestation period pine marten, fishers are members of the Mustelid or wea- lasts almost a year. Fishers have relatively low reproduc- sel family. As with most mustelids, the fisher possesses tive rates, producing one litter a year that averages an elongated body and has relatively short legs. About around two or three cubs, which are born and raised in a the size of house cats, adult fishers typically weigh be- tree cavity. Young fishers develop rapidly and are weaned tween four and 12 pounds and measure between 30 and at five to eight weeks, but do not disperse from the natal 47 inches from the nose to the tip of the tail. In most area and venture out on their own until about six months cases, male fishers are larger than females. In fact, males of age. usually weigh twice as much as females. The heaviest Fishers are solitary, opportunistic predators. The name fisher on record was a male trapped in Maine weighing is a misnomer; it does not reflect the animal's food hab- 20 pounds, 2 ounces. its. In fact, fishers seldom if ever hunt for fish. When hunt- At a distance, the fisher's long fur appears to be a solid ing, fishers do not seek out a specific prey item. Instead, glossy black. However, upon close inspection, the tri- they select prey based on abundance and catching ease. colored guard hairs surrounding the face and shoulders Consequently, the diet varies considerably by geographic give this area of the fisher's body a golden silvery sheen. region. In most parts of the fisher's range, mice, shrews, There is considerable individual variation in the color squirrels, chipmunks and porcupines are important prey of a fisher's fur as well as in the shape of white or cream items. In northern areas such as Wisconsin and Minne- patches of fur that occur on the under-side of the neck, sota, fishers often prey on snowshoe hares and grouse. chest and abdomen. Food acquired by scavenging also constitutes a signifi- Fishers need continuous forested areas for their sur- cant portion of the fisher's diet. For example, in many vival; they are unlikely to venture into unforested areas. areas, gut piles and deer carcasses provide fishers with Although conifers have often been described as an es- an abundant late-fall and winter source of food. When sential habitat component, fishers occur in both conifer available, apples, nuts and other fruits are readily eaten and mixed forests. by fishers. Most people familiar with fishers are aware of their Because of their varied diet and low densities, fishers extraordinary ability to climb trees. High above the for- do not appear to affect most prey populations. Fishers est floor, the agile animals locate cavities for denning, are among the few animals that regularly prey on porcu- rest in abandoned owl and hawk nests, or pursue squir- pines, though, and are known to control porcupine popu- rels, porcupines and other prey. Fishers do travel exten- lations. In fact, some states have reintroduced fishers for sive distances over land, though, and most foraging oc- the purpose of reducing porcupine numbers. curs on the forest floor. Like many solitary predators, fishers maintain low Fishers in Pennsylvania population densities and a large home range. Home ranges may approach 30 square miles for males and about When pioneers began settling here, fishers were widely 12 square miles for females. Female fishers are sexually distributed throughout our forested regions. Unfortu- mature when one year old, while males don't normally nately, the animals were unable to cope with the com-
58 bined forces of unregulated trapping and timber cutting this handsome, native component of the state's wildlife community to northcentral Pennsylvania. during the 1800s and, as a result, fishers were essentially Based on examination of potential fisher habitats, the eliminated from the commonwealth by the early 1900s. Declines in fisher populations were not unique to expansive forested landscape of northcentral Pennsyl- Pennsylvania. Historical records indicate that fishers vania — areas from the Allegheny National Forest to eastern Sullivan County — were identified as potential occurred throughout forested regions of Canada and the northern United States. In the eastern United States, fish- fisher habitat. In December 1994, the first fishers were released, into the Sproul State Forest in Clinton County. ers ranged from Maine to North Carolina. Many of these populations also suffered severe declines because of over Since that time, and including those in the initial release, trapping and destruction of forested habitats. about 160 fishers have been reintroduced in the com- Because of improved timber and furbearer manage- monwealth. All were obtained from New York and New ment, fishers have recovered in other portions of their Hampshire. To assure that adequate forested habitats persist for long-term sustainability of fisher popula- historic range. In fact, reintroduction projects tions, all reintroductions occurred on large tracts have restored fisher populations to West of public lands managed by the Pennsylvania Virginia and the Catskill Mountains in Bureau of Forestry, Game Commission southeastern New York. Fishers rein- or Allegheny National Forest. troduced into West Virginia have ex- The foremost purpose of the rein- panded their range to include for- troduction project is to restore a com- ested habitats in western Mary- land. Fishers in Maryland have ponent of Pennsylvania's wildlife heri- been gradually expanding tage. Reintroduction of the fisher will their range towards Pennsyl- provide outdoor enthusiasts the po- tential to view one of North vania, and during the 1994 America's rarest and most interesting trapping season a fisher that pre- furbearers. Fishers may also serve as sumably dispersed from Maryland an important natural predator of por- was accidentally caught by a trapper in cupines. Although reintroduced fish- Somerset County in southwestern Pennsylvania. ers will initially be protected from To date, several fishers have been caught in Somerset County. Fishers from the Catskills also may eventually harvest, fisher fur is highly esteemed by the fashion in- expand their range to include portions of northeastern dustry, and the reintroduction may eventually result in Pennsylvania. an additional fur resource for Pennsylvania trappers. Return of large tracts of forested habitat in many ar- Because forested habitats are once again plentiful eas of Pennsylvania, regulated trapping seasons, and evi- throughout northcentral Pennsylvania, there is a high dence of success in reestablishing fishers in surrounding probability that a fisher reintroduction project can suc- states suggest that fisher populations can be restored to ceed. We hope, with continued wise forest and wildlife management practices, reintroduced fishers will form the portions of Pennsylvania. To accomplish this, the Penn- sylvania Fisher Reintroduction Project was initiated in nucleus of a population that expands throughout 1994 as a cooperative venture between Pennsylvania northcentral Pennsylvania and persists for the enjoyment of future generations of Pennsylvanians. State University and the Game Commission to restore Wildlife Notes are available from the Pennsylvania Game Commission Bureau of Information and Education Dept. MS, 2001 Elmerton Avenue Harrisburg, PA 17110-9797 www.pgc.state.pa.us An Equal Opportunity Employer
59 Flycatchers Wildlife Note — 43 LDR0103 by Chuck Fergus lows and nightjars, although not nearly so compressed or gaping. Bristles at the corner of the mouth may function as "feelers," letting a flycatcher make last-second adjustments before snapping its bill shut on prey. Keen eyesight lets a flycatcher spot insects and judge distances accurately. In addition to catching insects on the wing, flycatchers some- times hover near foliage and pick off insects and spiders cling- ing to the vegetation. Some species land and catch prey on the ground. Most of our flycatchers occasionally eat berries and seeds. Of our ten breeding species, most build open cups anchored to small branches of trees and shrubs. One, the Eastern yellow-bellied flycatcher, builds an enclosed nest on the ground. The familiar eastern phoebe plasters its nest against Wood-Pewee a rock wall or on a building rafter. And the great crested The tyrant flycatchers — Family Tyrannidae — flycatcher uses a tree cavity. In most cases, the female does are found only in the New World. The family name stems most or all of the incubating, while the male defends the from the aggressive, almost tyrannical, behavior of some nesting territory and helps feed the young. of the birds in this large group of more than 400 species, Flycatchers advertise their home territories using their most of which live in the tropics. Pennsylvania has ten voices; some employ a special "dawn song" given just before species. Flycatchers are often hard to identify, even for sunrise and rarely sung later in the day. Because many fly- veteran birdwatchers, because the birds are drab (the sexes catchers are so similar in appearance, individuals probably are colored alike) and tend to stay among thick foliage. recognize their own species by sound. Biologists believe that For all practical purposes, they are distinguishable only in at least several types, the distinctive song is innate, not by their songs. Flycatchers are perching birds, members learned, as is the case with most other birds, which learn to of Order Passeriformes, whose feet have three toes point- sing by listening to adults of their kind. ing forward and one toe pointing backward, letting them As insect eaters, flycatchers must vacate northern breed- perch easily on branches. ing areas in winter. They migrate at night. The various spe- Flycatchers catch and eat flies and many other insects, cies winter in open and forested habitats along the Gulf particularly flying ants, bees and wasps. In forested areas large Coast, on the Caribbean Islands, and in Central and South flycatchers may specialize in larger insects, medium size fly- America. In South America, an estimated 10 percent of all catchers may take slightly smaller prey, and small flycatch- birds belong to the tyrant flycatcher family. In much of their ers may zero in on the smallest insects. Such feeding stratifi- wintering range (which is probably their original or ances- cation reduces competition and lets several species use the tral home, whence populations expanded their breeding same area. Also, different species prefer subtly different habi- ranges eons in the past), flycatchers are vulnerable to habi- tats, with varying amounts and densities of undergrowth and tat loss and fragmentation as large forested tracts are logged degrees of canopy shading. or converted to agriculture. When foraging, a flycatcher sits upright on a perch, scan- ning its surroundings while waiting for an insect to approach. ( Contopus cooperi ) — Although Olive-Sided Flycatcher The bird darts out in swift, maneuverable flight, snatches once fairly common in Pennsylvania, this species may or an insect out of the air with its beak, and eats it on the spot may not breed in the state today. Its white throat and breast or returns to the perch to eat the meal. Several adaptations contrast with dark olive sides. A fairly large (seven to eight help a flycatcher catch insects. Its drab plumage makes the inches long), big-headed flycatcher, the olive-sided inhab- waiting bird hard to see (not just by its prey, but also by its cool coniferous forests, generally near water. The male hawks that hunt for flycatchers and other small birds). The plus a song that has been ren- pip pip pip, sounds a repetitive bill is flat and wide, suggesting somewhat the bills of swal- hic-three-beers . Individuals sit high in dead snags dered as
60 ting, they occasionally flip their tails up and down. Ex- or branches, sally forth to catch prey — mainly wasps, tremely difficult to identify in the field, they are usually winged ants and bees — and return to the perch to eat. distinguished by voice and habitat. Olive-sided flycatchers place their cup-shape nests in trees 40 to 70 feet above the ground, among dense twigs or The Yellow-Bellied Flycatcher needles; three young are usual. The main breeding range Empidonax ( flaviventris ) lives in the deep shade of coniferous woods is in Canada; the species migrates north through Pennsyl- and cold bogs. A shy bird and rare in Pennsylvania, it in- vania as late as mid-June and leaves again in mid-August, habits remote uplands in a scattering of our northern coun- to winter in the rain forests of South America. This ties. The call is a quiet, ascending long-range mi- . The cup-shape nest is gration has chu-wee built of rootlets and mosses earned it the Eastern Wood-Pewee nickname and is hidden on or near the ground, in a cavity "peregrine of among the roots of a flycatchers." fallen tree, in a hum- mock of sphagnum Eastern moss, or at the base Wood-Pewee of a conifer. The spe- Contopus ( cies nests mainly in )— virens Canada, as far west as The eastern the Yukon Territory, wood-pewee with all individuals breeds apparently migrating throughout through the East. eastern North America from The Acadian Fly- southern Canada to ( Empidonax catcher the Gulf of Mexico. It ) nests mainly virescens is found in all counties in in the Southeast U.S., Pennsylvania. To locate this and Pennsylvania is near drab, olive-gray, sparrow-size bird, lis- the northern limit of its range. The type, or first, example ten for the male's oft-repeated namesake call — pee- of the species was discovered near Philadelphia in 1807 — which is given throughout the day but particu- o-wee by the Scottish-born ornithologist Alexander Wilson. The larly at dawn and dusk. Pewees use almost every wood- species is misnamed, since it does not inhabit Acadia, the land habitat, including woodlots, woods edges, mature for- former French colony centered on Nova Scotia. The ests (both deciduous and mixed), parks, and urban areas Acadian flycatcher lives in moist woods near streams and with shade trees. They perch in one place for an extended requires large areas of contiguous forest. The male sounds period, flying out to snag passing insects; one study found spit-chee! a low, sharp an average perching height of 35 feet above the ground. The Acadian often chooses a beech tree in which to Pewees eat flies, beetles, small wasps, and moths. They build its frail, hammocklike nest; stems and grasses dangle also consume elderberries, blackberries, and fruits of dog- from the nest, giving it an unkempt appearance. Acadian wood and pokeweed. flycatchers winter mainly in the rain forests of Colombia Males defend breeding territories of two to six acres. and Ecuador, where they sometimes follow mass move- Pairs begin nesting in late May. The nest is a compact cup ments of army ants and prey on insects set to flight by the woven of plant matter, hairs and spider silk, its outer sur- creeping columns. faces studded with lichens; it looks like a larger version of the ruby-throated hummingbird's nest. The three eggs The Alder Flycatcher ) and the ( Empidonax alnorum are incubated by the female and hatch after 12 or13 days. ) were, until the 1970s, Empidonax traillii ( Willow Flycatcher Both parents feed the young, which make their first flights considered to be one species, Traill's flycatcher (named by at 14 to 18 days. Blue jays are major predators, taking John James Audubon for Dr. Thomas Traill, one of his sup- both eggs and young. Most perching birds stop singing porters). However, the two types have different voices, use regularly in late summer, but male wood-pewees keep up slightly different habitats, build different kinds of nests, and their chanting until the autumn migration. The species fee-bee-o and the are reproductively isolated. The alder sings departs from Penn's Woods in August and September, with ; the alder builds a loose cup for a nest, usu- willow fitz-bew a few individuals hanging on until October. Wood-pewees ally within a few feet of the ground, while the willow winter in the tropics from Panama to Bolivia, in shrubby flycatcher's nest is compact and felled, and often situated woods and along forest edges. higher above ground. Both alder and willow flycatchers nest in thickets of willows, alders and other shrubs, but the wil- Yellow-Bellied, Acadian, Alder, Willow, and Least Fly- low flycatcher tends to use drier, more-open sites. In Penn- ( species) — These small flycatchers catchers Empidonax sylvania, alder flycatchers nest mainly in the north, while (around five inches in length) have olive-colored backs and willow flycatchers nest statewide, with the fewest records heads, pale breasts, and pale eye-rings and wingbars. They coming from the northcentral region. spend much of the day hunting from a perch. When sit-
61 The Least Flycatcher, Empidonax minibus, is the small- est of the Eastern Empidonax flycatchers and probably the most common. It lives along woodland edges and of- ten perches in the open. The male calls out an emphatic Eastern chebeck! , accented on the second syllable. The least fly- Phoebe catcher eats small wasps, winged ants, midges, flies, beetles, caterpillars, grasshoppers, spiders, and berries. The species sometimes nests in loose colonies. The nest, a neat cup, is usually placed in a vertical fork of a branch in a small tree or sapling. The three to five eggs are incu- bated for 13 to 15 days. The least flycatcher's breeding range stretches from western Canada to Nova Scotia and south in the Appalachians to Tennessee and North Caro- Empidonax minimum is fairly common across much lina. of Pennsylvania, except for the southeast, where it is ab- sent. In autumn, adults migrate ahead of juveniles to win- tering grounds in Mexico and Central America. Eastern Phoebe Sayornis phoebe ) — Anyone who has ( spent time at a woodland cabin has probably come to know this jaunty medium-size (six and a half to seven inches) flycatcher. Phoebes breed statewide in Pennsylvania, ex- cept in heavily urbanized areas. They eat a variety of in- sects, including small wasps, bees, beetles, flies and moths. They often take prey from vegetation and from the ground, and they eat seeds and berries. The female builds a nest out of mud, moss, leaves, grass and hair, tucking the cup-shape structure into a sheltered spot beneath a rock ledge, against a stone wall, on a bridge beam or barn or porch support. A pair may use the same nest several Great Crested years in a row. The female lays four or five eggs and incubates them Flycatcher for around 16 days. Both parents feed the nestlings, which fledge some 16 days after hatching. Eastern phoebes typi- cally rear two broods per summer. One of the harbingers of spring, the first male phoebes arrive around mid-March; calls and they announce themselves with repeated fee-bee the species' characteristic up-and-down tail-flicking. In the Northeast, populations have risen since settlement, with phoebes taking advantage of nest sites created by human construction. The species winters in the Gulf states and Mexico. ) — Our Great Crested Flycatcher ( Myiarchus crinitus largest (eight to nine inches) flycatcher, the great crested sports a yellow belly, a gray breast, and rusty-red tail and wing feathers. When agitated, individuals erect a head crest. The species breeds in mature woods throughout Pennsylva- nia and eastern North America and can also be found in wooded suburbs, farm woodlots and orchards. Great crested flycatchers feed among the treetops, hopping from limb to limb and snapping up caterpillars, katydids, crickets, beetles and spiders, and by flapping out into openings and clearings to take moths, butterflies, beetles, bees and wasps. In late summer and fall, many wild fruits are eaten. The call is a loud, insistent wheep! Great crested fly- catchers defend their territories against intrusions by squirrels and other birds. They nest in tree cavities, in- cluding old woodpecker holes, as well as hollow fenceposts and artificial nesting boxes. (One nest was even found in the barrel of a cannon in Gettysburg National Military Park.) Both male and female bring in grass, weeds,
62 Eastern Kingbird Eastern Kingbird ) — This bold, Tyrannus tyrannus ( aggressive flycatcher breeds in open country across North America. Look for kingbirds in scattered trees along roads and streams, orchards, fencerows and forest clearings. The bird gets its name because it dominates other birds, includ- ing many larger than itself, driving them away from its terri- tory. Of all the flycatchers, kingbirds are among the easiest to locate and observe. They are about eight inches long and are dark gray and white, with a white-tipped tail and a small red streak on the head. Roger Tory Peterson described the species' call as "a rapid sputter of nervous bickering notes." Kingbirds feed on beetles, wasps, bees, winged ants, grass- hoppers, honeybees and many other insects. Kingbirds often attack crows, hawks and owls, flying high in the air, getting above the larger birds, and diving at them repeatedly. After driving off an adversary, a kingbird may perform a display known as "tumble flight," in which it glides back to the earth in stages, sometimes tumbling in midair. After mating, the female does not let the male help her build the nest and may actually drive him away until after the eggs hatch. The nest is a bulky cup seven to 30 feet-up in a bark strips, rootlets, and feathers, often building up this shrub, tree or snag. The two to five eggs hatch after 16 days. cushion as high as the entry hole. They have the curious Both parents feed the nestlings, which can fly after around habit of placing a shed snakeskin or scrap of cellophane 17 days; they may be fed by their parents for a month after among the nest material; some ornithologists speculate fledging, with family members sounding rapid kitterkitter calls that the crinkly foreign matter may deter nest predators. back and forth. Kingbirds have a very different lifestyle on Great crested flycatchers depart from Pennsylvania in their wintering range in South America, where they coexist September en route to wintering grounds in southern in flocks and switch to a diet of berries. Florida and from Mexico to Colombia. Wildlife Notes are available from the Pennsylvania Game Commission Bureau of Information and Education Dept. MS, 2001 Elmerton Avenue Harrisburg, PA 17110-9797 www.pgc.state.pa.us An Equal Opportunity Employer
63 Wildlife Note — 5 LDR0103 Red and Gray Foxes by Chuck Fergus Red and gray foxes are small, agile carnivores belong- and the "silver fox," simply a black individual with white- ing to the same family (Canidae) as the dog, coyote and tipped guard hairs giving a frosted appearance. The red wolf. Both red and gray foxes are found throughout Penn- fox always has a white tail tip, no matter the color phase sylvania. They are intelligent predators with extremely or shade of red fur (which also varies slightly in indi- sharp senses of sight, smell and hearing (A fox can hear a vidual animals). mouse squeal at about 150 feet). Foxes are swift runners and can swim if they have to. Both reds and grays are mainly nocturnal. The gray can Biology climb trees — it is the only member of the canine family with this ability. The red fox ( Vulpes vulpes ) is 22 to 25 inches in length, Foxes are "opportunists" when it comes to feeding. with an additional 14- to 16-inch tail, and weighs 8 to This means they will eat whatever is most easily obtained. ) is Urocyon cinereoargenteus 12 pounds. The gray fox ( Foods include mice, rats, rabbits, woodchucks, opossums, 21 to 29 inches in length, plus an 11- to 16-inch tail, and porcupines, domestic cats, chickens, insects, squirrels, weighs 7 to 13 pounds. Foxes look like they are heavier game birds, songbirds, bird eggs, fruits and grasses. than these weights, an impression created by their full, Foxes are also scavengers, feeding on roadkilled ani- thick fur. mals and winter kills. Diets of both reds and grays are The red has long, reddish-orange fur slightly darkened essentially the same, but different food preferences, be- on the back; black ears, legs and feet; and a long, bushy, havior patterns and preferred habitat often result in dif- white-tipped tail. The gray fox has a grizzled gray coat, ferent types and amounts of food eaten. Both species somewhat coarser than the red's, with buff-colored un- cache uneaten food by burying it in loose earth. derfur. The gray's tail is also long and Males are called "dog" foxes and females "vixens." In bushy, with a black streak running late winter, foxes can be heard barking at night, making down its length and a black tip. their presence known to members of the opposite sex. Dramatic color variations may Breeding usually takes place in February. occur in individual reds, al- Young are born following a 51-day gestation period though these are rare and for red foxes and a 63-day period for grays. Litters range show up more often in the spe- from 4 to 10 young, with 6 the average. Young are born cies' northern range, espe- in dens. The red fox usually enlarges a woodchuck bur- cially in Canada. These color row or may den in a hollow log; the gray may also den variations include: the "cross beneath the ground or in crevices in rocky ledges. Un- fox," with a dark stripe of hair derground dens for both species usually have several en- extending from the head down trances. the center of the back and Fox pups weigh about eight ounces at birth, and their transected by another dark eyes are closed for the first 8 to 10 days. They are nursed stripe over the shoul- by the female in the den for around a month. When the ders, thus forming pups emerge, both mother and father keep them supplied a cross-like with solid food until they are completely weaned after shape; the two or three months. "black They leave the den area in mid-July or August and fox," a may forage with their parents for another month until melanis- the family disbands. Foxes trapped in the fall are often tic red young ones, on their own for the first time and establish- fox; ing new territories. Both males and females are sexually
64 connaissance and tracking studies. The gray fox has much mature at 10 months and may breed during their first larger toe pads and a smaller foot than the red, so the winter. two can often be distinguished by their tracks. Red foxes seldom seek shelter in holes or dens during Movements in gray and red fox populations are basi- winter, preferring to sleep in the open with their bushy, cally of two types. The first is dispersal, or the move- well-insulated tails curled over their noses to keep them ment of young in late summer or early fall. Dispersal warm. Grays often hole up for three or four days at a time spreads the population out, with each young fox moving during severe weather. several miles — occasionally 50 miles or more — to set Foxes may be afflicted with many parasites, including up its own home territory. The second type of movement ticks, fleas, lice, mites, flukes and worms. Reds seem to is displacement, which is caused by habitat changes and be more susceptible to mange than gray foxes. Both spe- predation. There are also localized movements, the trav- cies can contract rabies. Diseases and parasites strike els of individual within their home territory or range. foxes the hardest when they overpopulate an area; this is From tracking studies, biologists estimate that a fox trav- nature's way of managing an excessive population. els an average of five miles in search of food on a winter Wildlife researchers have live-trapped foxes, tagged night. and released them. These studies have shown that foxes, Populations fluctuate and shift, often as a result of especially young adults, are susceptible to many limit- human activities such as logging, farming, construction ing factors, including trapping, hunting, highway mor- and hunting. Disease also plays a role. In areas where tality and coyote predation. A life span of 10 to 12 years mange outbreaks occur, red fox populations are often is possible, however. severely impacted. But foxes are very resilient. Both spe- cies seem to readily rebound from disease and other lim- Habitat iting factors, so long as the area they inhabit can provide food, escape cover and safe havens. Red and gray foxes generally favor different types of Proof of the resiliency of foxes was their ability to habitat. The red prefers sparsely settled, rolling farm ar- weather decades upon decades of persecution through eas with wooded tracts, marshes and streams. The gray bounties in Pennsylvania. Abolished in 1966, fox is more commonly found in brushy ar- bounties were a fee paid to people for each eas, swampy lands and rugged, mountain- fox they killed. Bounties were discontin- ous terrain. But both species are very ued because it was determined the mon- adaptable and can be found through- ies used to pay them were better spent out the state, sometimes in areas not on habitat enhancements. considered prime habitat. Foxes are often blamed for decreas- Red foxes seem less bothered by ing game populations, but most of the people than grays and often inhabit time the number of game animals heavily populated areas, although taken by foxes and other predators is they are rarely seen due to their noc- insignificant compared to other natu- turnal habits. There are countless sto- ral losses. When all facts are consid- ries of reds rearing young in suburban ered, habitat change is most often settings. Generally, if the area can pro- found to be the main contributor to vide food and shelter, foxes will con- lower small game populations. It's true sider it, especially since coyotes con- that foxes take grouse, pheasants, rab- tinue to push out, or displace, reds from bits and other game, but these are usually their historic haunts. "surplus" individuals, those animals that Grays are usually more aggressive than would likely die from other causes — accidents, reds and where the ranges of the two overlap, the disease, starvation, etc. — before the next breeding sea- gray is typically the dominant species. But there are ex- son. ceptions to every broad statement made about wildlife. More and more people are accepting predators as valu- Knowing that, you can figure somewhere out there are able members of our natural world. Foxes are no excep- places where reds rule or where the two species coexist tion. Their presence in Pennsylvania provides recreation without problem. and wildlife diversity, two important facets of any wild- life management program. Population Fox populations are affected by availability of food, habitat suitability, coyote predation and hunting and trapping pressure. Pennsylvania studies have documented Wildlife Notes are available from the that some high-use agricultural areas — with little cover Pennsylvania Game Commission for either prey or predators — had only one fox per 300 Bureau of Information and Education acres, or 2.1 foxes per square mile. Wooded and less Dept. MS, 2001 Elmerton Avenue heavily farmed areas had one fox per 50 acres or 12.8 Harrisburg, PA 17110-9797 per square mile, a high concentration. www.pgc.state.pa.us Fox populations can be measured by different meth- ods, including counting droppings on the snow, den re- An Equal Opportunity Employer
65 Wildlife Note — 51 LDR0103 Gray Catbird, Northern Mockingbird and Brown Thrasher by Chuck Fergus Gray Catbird These three species are among the most vocal of our birds. All belong to Family Mimidae, the "mimic thrushes," or "mimids," and they often imitate the calls of other spe- cies, stringing these remembered vocalizations into long, variable songs. Family Mimidae has more than 30 spe- cies, which are found only in the New World, with most inhabiting the tropics. The mimids have long tails and short, rounded wings. The three species in the Northeast are solitary (living singly, in pairs and in family groups rather than in flocks), feed mainly on the ground and in shrubs, and generally eat insects in summer and fruits in winter. The sexes look alike. Adults are preyed upon by owls, hawks, foxes and house cats, and their nests may be raided by snakes, blue jays, crows, grackles, raccoons, opossums and squirrels. Gray Catbird ( Dumetella carolinensis ) — The gray cat- bird is eight to nine inches long, smaller and more slen- der than a robin, an overall dark gray with a black cap Beetles, ants, caterpillars, and chestnut around the vent. Individuals often jerk their grasshoppers, crickets and other insects tails — up, down, and in circles. The species is named are common foodstuffs. Catbirds often forage on the for its mewling call, although catbirds also deliver other ground, using their bills to flick aside leaves and twigs sounds. They migrate between breeding grounds in the while searching for insects. eastern two-thirds of North America and wintering ar- Although not as talkative as the northern mocking- eas in the coastal Southeast and Central America. Gray bird, the catbird is still a versatile vocalizer. Its ability catbirds are abundant and statewide in Pennsylvania, comes in part from the structure of its syrinx, or voice inhabiting hedgerows, woods undergrowth, regenerating box, whose two sides operate independently, letting the cut-over land, shrubby areas near water, woods edges and bird sing with two voices at the same time. A catbird suburban plantings. They shun dense forests. calls out a rapid string of syllables — more than 100 types in some individuals — including squeaks, chitters, Catbirds eat wild fruits and insects. In summer the diet whistles, whines and songs swiped from other birds. The is around 60 percent fruit, and in spring, 20 percent fruit.
66 its wings, opening them to expose the white patches. The babble, which lasts up to 10 minutes, is frequently punc- species lives year-round on its range, which overlays most tuated by the familiar catlike mewl. of the lower 48 states and includes southern Canada, the Catbirds are monogamous. They nest from May into Caribbean islands and Mexico. Mockingbirds live in July and usually raise two broods per year. The nest, sub- towns and cities, where they often forage on lawns and in stantial and deeply cupped, is placed in a dense thicket, thickets, road margins, woods edges, cut-over lands and briar patch, vine tangle, or shrubby tree, three to nine farms. They like a mix of low shrubs and open terrain. In feet above the ground. The female lays three to five eggs, Pennsylvania mockingbirds are most common in the which are a dark greenish blue and unmarked. Brown- southeast, the southcentral (although not in the moun- headed cowbirds often lay their eggs in catbird nests, but tains) and the southwestern regions. catbirds almost always recognize the parasitic eggs (which About half of the diet consists of insects and half of are pale and dotted with brown) and pitch them out of native and cultivated fruits. When hunting for insects, a the nest. Catbirds destroy eggs and nestlings of other spe- mockingbird will run along on the ground in short grass, cies, including wood-pewees, robins and sparrows; biolo- stopping and lunging for its prey: beetles, ants, bees, gists don't know whether this behavior represents an at- wasps, grasshoppers and others. Mockingbirds also eat tack on competitors or a feeding strategy. Parents feed spiders, earthworms, snails and sowbugs. In fall and win- their own young mainly on insects and spiders. Incuba- ter berries and fruits make up most of the diet, including tion takes two weeks, and the young leave the nest 10 or grapes, apples, barberries, hawthorn, elderberries and (a 11 days after hatching. particular favorite) multiflora rose hips. Mockingbirds sometimes drive off cedar waxwings and other birds, with ) — The slen- p Mimus lottos Northern Mockingbird ( yg ol whom they compete for fruit. In winter mockingbirds may der, robin-size northern mockingbird has a gray back, a pale visit feeding stations for seeds and suet, pugnaciously breast and conspicuous white patches on the tail and wings: chasing other birds away. when foraging, a mockingbird will often stop and flick Both male and female mockingbirds sing, but the males are the true virtuosos. They mimic snatches of other birds' songs, calls of crick- ets and frogs, dogs barking and even me- chanical noises such as squeaky hinges and squealing tires. A male's repertoire increases as the bird ages and may ultimately include more than 150 distinct song types. Usually an individual repeats one sound or song three to six or more times, then switches to another song, and so on, singing for minutes on end. (Brown thrashers usually repeat each song once, while catbirds do not repeat.) In the spring, male mock- ingbirds sing to establish territories and attract mates, starting around an hour before sunrise. They sing in flight, on the ground, from perches, when building nest foundations, during and after copula- tion, while foraging — even with food clutched in their bills. Unmated males may sing during the night, usually from a hidden perch. Mockingbirds sing from March to August (the breeding season) and from late September into November (while establishing fall and winter feeding territories). Mockingbirds are mainly monogamous. Court- ing males and females chase each other in flight. The nest is a bulky cup built in a dense shrub or a tree, usually 3 to 10 feet above the ground. The female lays three or four greenish to bluish gray eggs, blotched with brown. She incubates them 12 to 13 days. Both sexes feed the young, which fledge after 12 days, although they're not strong fliers for another week. At fledging, the male may continue to feed the young while the fe- male lays and begins incubating the next Northern clutch. This division of labor lets mockingbirds produce two and sometimes three broods (up to four Mockingbird in the South) during each breeding season. Mockingbirds aggressively defend their nests, driving away predators and attacking humans who venture too close.
67 tract mates. The song is full of improvisation and mim- Northern icry of other species, including flickers, titmice, cardi- nals and thrushes; observers have reported more than Mockingbird 3,000 song types, the largest repertoire of any North American bird species. The alarm call is a crackling note that may sound like a loud, smacking kiss. After mating, males continue to sing but in a quieter tone. Territories are 2 to 10 acres. The nest, hidden in dense, tangled cover, is built mainly of sticks and twigs and lined with cleaned rootlets. Thrashers place their nests from 1½ to 20 feet above the ground and occasionally on the ground itself. The female lays four eggs, which are pale blue and freck- led with reddish brown. Both parents incubate. The eggs hatch after 11 to 14 days, and the young leave the nest 9 to 13 days after hatching. They stay in the vicinity, and their parents bring them food. Two broods per year are usual; some thrashers switch mates between same-season broods. In Pennsylvania, nesting runs from early May to the end of July. Brown thrashers in southern areas are permanent resi- dents, but most of those breeding in the Northeast leave the Some mockingbirds spend the whole year as a pair on a region in September and October and take up residence in single territory, while others, particularly in the northern thickets in the Gulf states. Statewide, the brown thrasher part of the range, use different breeding and wintering terri- population seems to have decreased by about four percent a tories. In the north, some individuals may migrate south in year since the mid-1960s, perhaps because of cowbird para- winter. Young disperse up to 200 miles from where they sitism, nest predation and the growth of old fields into hatched. Ornithologists believe the spread of multiflora rose mature woodlands. (an invasive species once planted widely for wildlife habi- tat) and the planting of ornamental shrubs (especially , or firethorn) provided key winter food and shel- Pvracantha ter, aiding the mockingbird in a northward population ex- pansion that has gone on for close to a century. ( Toxostoma rufum ) — The largest of our Brown Thrasher three mimics, the brown thrasher has an 11- to 12-inch Brown length, half of which is tail. Plumage is rich reddish brown Thrasher above, heavily streaked below. The name "thrasher" may come from the bird's habit of thrashing the ground litter, using its long, curved bill to sling aside leaves and dirt while foraging. Brown thrashers breed across the east- ern two-thirds of North America, with a range simi- lar to that of the gray catbird. The species nests statewide in Pennsylvania, although it's more common in the southern than the northern counties. Brown thrashers prefer brushy, thorny places, including hedgerows, thickets, forest margins and clearings and old fields overgrown with shrubs. Shyer than catbirds and mockingbirds, they are less likely to live around people, and they often flee into escape cover at the sight of a human. Brown thrashers feed on insects (more than half the annual diet), berries, small fruits, seeds and nuts, including many acorns. Occasionally they take crayfish, lizards and small frogs. The best time to observe brown thrashers is in April, before nest building has commenced, when males sing from high, exposed perches to at-
69 Wildlife Note — 16 LDR0603 Heron Family by Chuck Fergus Have you ever hiked along the edge of a quiet stream rest of the plumage clean and dry. Herons preen with a or marsh and startled a big, long-legged bird that flapped serrated middle claw. slowly out of the water, leaving only a widening ripple? Males are aggressive and defend small territories in Chances are good that the bird was a heron. breeding season. They fight (although rarely causing There are about 60 species of herons distributed over physical damage); sound harsh calls; go through elabo- most of the world, except in the extreme northern and rate, instinctive motions such as raising their wings, southern regions. Herons are most common in the trop- stretching their necks, fluffing their feathers, or erecting ics. Herons, bitterns and egrets are closely related, be- their crests. Some also put on spectacular flight routines. longing to the family Ardeidae of the order In most species, bright colors appear on the bill, legs or Ciconiiformes. Other close avian relatives include storks, in the bare skin around the eyes. ibises, spoonbills and flamingos. Often the male begins building a nest to attract a mate; Herons are wading birds with long, slender legs, long then the female takes over construction and the male necks and long, heavy bills tapering to a sharp point. brings sticks and twigs. Mated herons defend a zone im- Their wings are broad and rounded, their tails short. Most mediately around their nest against intrusion of other herons, especially the larger ones, are graceful in form birds. Some species nest in colonies (sometimes called and movement. heron rookeries), while others are solitary nesters. Her- Herons are predators, feeding on animal life (fish, ons may nest in mixed colonies (great blue, black- and frogs, crayfish, snakes, insects, invertebrates and small yellow-crowned night herons building nests in the same rodents) found in shallow water and along the shoreline. grove of trees). Or, in certain parts of their range, they Herons swallow food whole and later regurgitate pellets may nest with cormorants, pelicans and ibises. of indigestible matter. They inhabit both freshwater and After breeding, 3 to 6 unmarked bluish, greenish, or saltwater areas. In Pennsylvania, they're found on lakes, brownish eggs are laid in a nest of sticks in a tree (herons reservoirs, ponds, rivers, woods streams, bogs, marshes and egrets) or a nest of grasses on the ground (bitterns). and swamps, where they typically stand at the water's edge The eggs are incubated by both parents for 2½ to 4 weeks, or walk slowly through the shallows. They may also perch depending on the species. Some herons begin incubat- in trees near or over water. ing immediately after the first egg is laid, so that young Herons are shy birds. When approached by humans, hatch at intervals and differ in size. Young remain in the they usually take off in slow flight, with head and neck nest 2 to 3 weeks. drawn back in an S-shape and legs held straight to the At first, parents regurgitate pre-digested liquid food rear. Most herons are strong fliers, propelling themselves to their nestlings. Later, they bring partly digested food, with deep, pumping wing strokes. and finally whole fish, frogs, snakes and other items. A Certain adaptations help a heron wade about and growing heron or bittern will grasp the base of its parent's catch prey in shallow water. The most obvious is its legs, bill in a scissors-grip and wrestle with it. This triggers an which elevate the bird above the water surface. The toes impulse in the adult either to drop or regurgitate the food. are long and flexible for walking or standing on soft The following herons and allies, which breed in Penn- ground. The bill is sharp-tipped, but it's used for grasp- sylvania, are covered in this Wildlife Note: great blue ing, not impaling. The long, muscular neck delivers a heron, green-backed heron, great egret, black-crowned lightning-quick blow, with plenty of force to penetrate night heron, yellow-crowned night heron, least bittern the water and seize a fish. and American bittern. All are migratory, generally breed- Herons have well developed "powder down," areas of ing in northern areas and migrating south in autumn. feathers with tips that continually disintegrate into pow- Some species migrate in flocks, some in small bands, and der. Preening helps distribute this powder, which absorbs some individually. and removes fish oil, scum and slime, thus keeping the Other herons occasionally visit Pennsylvania. The
70 Great Green Egret Heron Great Blue Heron little blue heron is a migrant occasionally spotted in and habitat preservation and enhancement work on State April, and later in July and August. Little blues are 22 Game Lands. Areas such as Pymatuning, Middle Creek inches in length, with brownish heads and bluish-gray and Shohola provide many acres of excellent marshland bodies. The cattle egret was first observed in Pennsylva- habitat. In propagation areas (where human visitors are nia in 1956 and is now common in some areas; its plum- not permitted to intrude), herons have ample isolated age is white, with brownish plumes on the back, lower territory in which to breed and raise young. breast and crown, and a reddish bill and legs. The snowy egret (white, with black legs and bright yellow feet) is Ardea herodias Great Blue Heron ( ) — This bird prob- seen in spring and late summer. These four species typi- ably comes to mind most when the word "heron" is men- cally breed farther south or along the Atlantic coast. tioned. It's the largest of the dark herons, 38 inches long Snowy and cattle egrets nested in Pennsylvania during (as seen in the field) with a 70-inch wingspread. A great the 1970s and '80s. Their colony on the Susquehanna blue heron's head is largely white (with a feathery black River's Rookery Island in Lancaster County was aban- crest), the underparts are dark gray, and the back and doned in 1988. wings are grayish-blue. The legs are dark. Wading birds are part of the complex web of life in When hunting, a great blue walks slowly through the the marshes and along the water's edge. When several shallows or stands in wait, head hunched on its shoul- species of herons inhabit a waterway, lake or swamp, spe- ders. Favorite foods include fish (up to a foot in length), cialized feeding patterns often develop. The great blue water snakes, frogs, crayfish, mice, shrews and insects. heron usually wades in deeper water, looking for large Individuals are believed solitary except in breeding sea- fish. Common egrets hunt the slightly smaller fish found squawks . son. Call: three or four hoarse closer to shore. The green-backed heron waits motion- Great blue herons inhabit saltwater or freshwater ar- less for its prey near a log or bank; bitterns snatch frogs eas near trees suitable for nesting — the more remote and tadpoles among the reeds. On dry ground, cattle and inaccessible, the better. They nest singly, in colonies egrets forage for grasshoppers and other insects stirred and among the nests of other herons, often in the same up by livestock, while the black- and yellow-crowned tree. The nest is a platform of large sticks lined with fine night herons patrol shallow waters in the late evening twigs and leaves and built in a sturdy crotch or on a limb. and at night. Its outside diameter is 25 to 40 inches. The male brings Although mainly predators, herons are also prey for nesting material to the female, which does most of the some species, including foxes, minks, hawks and espe- actual building. Nests may be used several years. cially raccoons. Crows and tree-climbing snakes may rob The female lays 3 to 6 (usually four) pale bluish-green, unguarded nests. Few predators dare tackle an adult unmarked eggs. Incubation is by both sexes and takes 28 heron, especially one of the larger species. days. Both parents feed the young, which are ready to At one time herons were slaughtered for their plum- leave the nest in three weeks. age, which was used to decorate women's hats, but today In spring, the great blue heron is a common migrant they have little to fear from humans. They're protected in March and April; in summer, a breeding resident, with by federal and state laws. However, herons are affected the greatest concentrations of nests occurring in the by loss of habitat, especially when marshy or coastal ar- northwestern counties. The species generally breeds eas are developed. across the northern United States, southern Canada and Herons, and many other species of wildlife, benefit Alaska. In the fall, great blue herons pass through our from Pennsylvania Game Commission waterfowl projects state from July to October. Some remain as winter resi-
71 Yellow-Crowned Night Heron Least Bittern Black-Crowned Night Heron Immature Night Heron American Bittern dents, hanging out along waterways and other open wa- white body plumes, used to feather women's hats. Strong ter. The species winters principally along the Atlantic conservation laws saved the species, which is repopulat- coast, the southern states and Central and South America. ing its former range. A great egret's plumage is pure white, the bill yellow, Green-Backed Heron ) — This small ( Butorides striatus and the legs and feet glossy black. It's the largest white heron is found in ponds and along wooded streams. Its heron likely to be observed in Pennsylvania, with a 32- length is 14 inches, its wingspread 25 inches. The bluish- inch length (not counting tail plumes), a 55-inch wing- green back and wings give the bird its name; underparts spread, and a standing height of about two feet. Preferred are dark, while the neck and head are reddish-brown and foods are fish, small mammals, amphibians, and insects. the crown is black. This bird may appear all dark from a Egrets inhabit swamps, brushy lake borders, ponds, distance, especially on a cloudy day. Immatures resemble Susquehanna River shallows, islands and mudflats. Nests American bitterns. are in colonies, sometimes with other heron species, usu- A green-backed heron flies with deep wingbeats. Its ally 10 to 50 feet up in trees. In forests with large trees — kew call is a sharp, descending . The green-backed heron beech and red maples are favorites — egret nests may be feeds on fish, frogs, insects, worms, lizards and salamanders, 80 feet in the air, along with the nests of great blue her- hunting early in the morning and late in the afternoon. ons. Nests are made of sticks and twigs, two feet in diam- Green-backed herons usually nest in shrubs or trees eter, sometimes lined with leaves, moss and grass. Eggs: 3 overhanging the water, but sometimes in orchards and to 4 oval, blue or greenish-blue, unmarked. Incubation is groves away from any water source. A pair may nest by performed by both sexes and takes 23 to 24 days. itself or in a loose colony of other herons (the green is Breeding resident egrets arrive in April. Post-breed- not as gregarious as the great blue). The nest is a plat- ing dispersal occurs from July to October. Migrants also form of twigs and sticks lined with finer material; some pass through the state at this time. Egrets are rare winter nests are so shallow and flimsy that the eggs can be seen residents, sometimes staying on the John Heinz National through the bottom. The male selects the nesting site and Wildlife Refuge at Tinicum in Delaware and Philadelphia starts building, and the female finishes the task. Outside counties. nest diameter is 10 to 12 inches. Four to six oval, pale blue or green unmarked eggs are laid, which both sexes Nycticorax ( Black-Crowned Night Heron incubate for 20 days. Some pairs raise two broods. nycticorax ) — Night herons have heavy bodies and short, In spring, green-backed herons are common April-May thick necks. A species of special concern in Pennsylva- migrants. In summer, they are breeding residents (the spe- nia, this bird is 20 inches in length, with a 44-inch wing- cies breeds throughout the eastern United States, Cen- spread. Adults have glossy greenish-black backs, pale gray tral America and in Arizona and Texas); in fall, they're or white undersides, and yellow-orange legs; three white, common July to September migrants, with stragglers into 6-inch plumes extend back from the black crown. November. Green-backed herons rarely winter as far north Immatures are heavily streaked with brown and lack the as Pennsylvania. red eye of the adult. In flight, black-crowned night herons resemble slow, ( Great Egret ) — The great egret — Casmerodius albus light-colored crows. They fly in loose flocks and often also called the common or American egret — was nearly roost communally. Usually inactive during the day, they gone from the United States by the early twentieth cen- hunt at night. Food: mainly fish, some eaten as carrion; tury. For years the birds had been killed for their long, also dragonflies, other insects, crayfish, worms and small
72 rodents. Call is a single irregularly, wherever suitable habitat exists. kwawk , most often given at night. These herons adapt to extremely varied habitat: fresh, The species nests on the ground in marshes, bogs or salt and brackish waters, forests, thickets and even city brackish water areas. Nests are 6- to 10-inch wide plat- forms of dead plant material interwoven with living plants, parks. They nest close together in small to large colonies — sometimes with other species — in trees, shrubs or on often built in thick cattails, tall grass or under bushes 1 to 8 feet from the water. The female lays 4 to 5 pale blu- the ground in cattail stands. Nests are built of sticks, twigs ish-green, unmarked eggs. During incubation (17 to 20 or reeds, and sometimes are lined with finer material. Both days), adults do not fly directly to their nest: they land sexes build (construction takes 2 to 5 days). Females lay nearby and approach quietly through the ground cover. 3 to 5 pale blue or green unmarked eggs, which hatch in 24 to 26 days. Least bitterns are rare April to May spring migrants. In summer, they're rare breeding residents (the species In spring, black-crowned night herons occupy nest breeds throughout the East and in parts of the western colonies in April. In summer, they are breeding residents (rare in central and northern Pennsylvania, but fairly com- United States). In fall, they are rare August to Septem- ber migrants. They winter principally in Florida, Texas mon in the southern counties). Fall: August and Septem- and Central America. ber migrants. Winter: residents in the southeast and other southern counties. Most individuals, however, go farther south. ) — The American Bittern ( Botaurus lentiginosus American bittern is 23 to 24 inches long, has a 45-inch ( Nyctanassa Yellow-Crowned Night Heron wingspread, and a 1½-foot standing height. Plumage is violacea ) — A endangered species in Pennsylvania, this dappled dark and light brown, with a black streak on each bird is similar in size and body configuration to the closely side of the upper neck, and yellow legs. In flight, which is related black-crowned night heron, except that the yel- slow and deliberate, the black flight feathers are distinc- tive. low-crowned has slightly longer legs (standing height This shy, elusive bird, inhabits the tall vegetation of about 1½ feet). It has a yellow patch on its head, a gray freshwater marshes. Most active at dusk and at night, it body, and a black and white face. The call, a strident , is slightly higher-pitched than that of the black- preys on mice, snakes, lizards, salamanders, frogs, insects, kwawk etc. An individual hunts by standing motionless and wait- crowned. ing for prey to pass. Like the least bittern, the American Yellow-crowned night herons hunt mainly at night but bittern hides by freezing with its bill pointed up. On breed- also at times during the day. They eat frogs, fish, sala- manders, lizards and insects. Catching crayfish is their ing grounds, it makes a hollow croaking or pumping sound, oonck-a-tsoonck specialty. They nest singly and in small colonies, some- , from which it earned the colloquial name times with other herons. The stick nest is built in a tree or "thunder pumper." It can be heard for up to a mile across shrub and sometimes lined with fine twigs, rootlets or a marsh. The species does not flock. Favored habitat: marshes, bogs and swamps, especially leaves. Both sexes build, or they may re-use an old nest. where cattails and bulrushes grow. Solitary nesters, bit- This species is more secretive in its nesting habits than terns build 10- to 16-inch platforms of dried cattails, reeds other herons, with the exception of bitterns. Eggs: 3 to 4 or grasses on dry ground among tall vegetation. Eggs: 3 to smooth, pale bluish-green, unmarked. Incubation is by both sexes. 7, usually 4 to 5, buffy brown to olive-buff, unmarked. Incubation, mainly by the female, lasts 24 days, begin- In spring, yellow-crowned night herons migrate through our state in April and early May. In summer, they are breed- ning with the first egg. In spring, American bitterns are uncommon migrants ing residents in the southeastern area: most nesting is con- in April and early May. In summer, they are breeding resi- centrated in Cumberland, Lancaster and Montgomery dents, nesting across the northern United States and counties. In fall, they are rare August to October migrants; southern Canada. They are uncommon fall migrants from and they winter principally in the southern United States and Central and South America. August through September. Some birds winter in our state, but the majority migrate to the southern United States and Central America. Least Bittern ) — The least bittern, Ixobrychus exilis ( American bitterns have declined precipitously during the smallest of our herons and a threatened species in the twentieth century. They're now listed as a threatened Pennsylvania, is 11 to 14 inches long with a 17-inch wing- spread. It has large buffy wing patches; a black crown, tail species in Pennsylvania. and back; and yellow legs. This shy bird is not often ob- served, partly because it usually hides in tall grasses and sedges at the hint of trouble, but mostly because the bird is predominantly nocturnal. A weak flier, the least bit- tern would rather run from danger or "freeze" by standing Wildlife Notes are available from the motionless with its long, tapered bill pointed upward (thus Pennsylvania Game Commission blending into the marsh background like a stick or reed). Bureau of Information and Education Food: insects, salamanders, fish, frogs and tadpoles. Their Dept. MS, 2001 Elmerton Avenue coos. call is three or four low, soft Harrisburg, PA 17110-9797 Least bitterns regularly breed in emergent and brushy www.pgc.state.pa.us wetlands in the glaciated wetlands of northwestern coun- ties and at Presque Isle. The species nests elsewhere, but An Equal Opportunity Employer
73 Wildlife Note — 49 LDR0103 Belted Kingfisher by Chuck Fergus While paddling down a stream, I've often startled — and been startled by — a kingfisher. The bird takes off from its perch, sounding an alarm call that rattles down the creek's corridor. It flashes downstream, two or three strokes of its blue-gray wings, then a short glide, then more wing-pump- ing, sometimes skimming so low that its wingtips seem to brush the water's surface. When the bird reaches the end of its territory, it quietly loops around behind me. Sometimes I'm scolded by another kingfisher at the next bend in the lows it headfirst. Kingfishers take whatever types of fish stream. The belted kingfisher, Ceryle alcyon belongs to Fam- , inhabit a given waterway, from bullheads to sticklebacks to ily Alcedinidae. Six species of kingfishers live in North and trout. When heavy rains make stream waters cloudy, king- South America, and around 80 inhabit other parts of the fishers may turn to crayfish. They also eat mollusks, insects, globe. (Australia's laughing kookaburra is a well-known reptiles, amphibians, and the occasional small bird or mam- member of the family.) In North America the banded king- mal. After feeding, a kingfisher coughs up a small pellet fisher breeds from Alaska to Labrador and south to Florida, composed of indigestible matter such as bones and fish Texas and California. It winters in the lower 48 states where scales. open water remains available; some individuals go as far as People often hear these alert birds before seeing them. northern South America. The rattle call is given freely, both as an alarm signal and during territorial disputes. Mated pairs use a softer version Biology of the same call to communicate with each other. Kingfish- ers become active just before sunrise, when they forage and A kingfisher has a stocky body and a large head with a patrol their territories; they do most of their feeding be- ragged-looking double-pointed crest. The beak is sturdy and tween seven and 10 in the morning and are less active dur- sharply pointed, the tail is short, and the feet — especially ing midday. At night they roost in trees. Kingfishers are when considered along with the outsize head — appear to solitary except when breeding. Both males and females de- be absurdly small. Adults are 11 to 14 inches in length and fend individual territories, calling stridently and flying at weigh five to six ounces. The white neck ring and breast and attacking intruding kingfishers. A territory may include stand out against the blue-gray body plumage. The female 1,000 yards of stream or lake bank. has a belt of rusty feathers adorning her sides and breast, Migrating kingfishers return to Pennsylvania in March which the male lacks. and April (others may have stayed through the winter, if Kingfishers live along the banks of streams, rivers and streams did not freeze over). The male establishes and de- lakes, where they catch fish near the surface or in shallow fends a breeding territory; once a female is attracted and water. They mainly take fish that are four or five inches the two pair up, she also defends the territory. During court- long or shorter. Kingfishers hunt from perches — branches, ship, the male feeds the female. After mating, the male, utility wires, pilings and bridge supports — or hover above followed by the female, may soar and then dip close to the the water while scanning for prey. A kingfisher dives into surface of the water. Breeding peaks in early May. the water with its eyes closed and uses its bill to grab its Kingfishers nest in burrows that they dig into steep prey. After catching a fish, the bird flies back to its perch, banks above streams, in road cuts, and in sand and gravel stuns the fish by whacking it against the perch, and swal- pits. Often the burrows are a few feet below the top of
74 the bank, where topsoil gives way to sandier subsoil. Bur- Habitat rows are usually near or along the water, but sometimes they're a mile or farther away. Both birds excavate the Kingfishers inhabit streams, rivers, ponds, lakes0 and es- burrow, a task that may take three days to two weeks. tuaries. Individual territories often center on stream riffles, The tunnel is three to four inches in diameter, slopes up- which are good fishing spots. Kingfishers prefer open run- ward, extends a yard or two into the bank, and ends in an ning water that is not turbid. On lakes they use sheltered unlined chamber 8 to 12 inches across and six or seven coves and shallow bays. For nesting they require earthen inches high. Before entering, an adult will land on a con- banks where burrows can be excavated; during breeding, venient perch, give the rattle call, and fly straight into kingfishers are sensitive to disturbance by humans and may the burrow opening. To tell whether a burrow is in use, desert an area if bothered too frequently. In winter they look for twin grooves on the outer lip made by the king- resort to rocky coastlines, swamps, brackish lagoons, ox- fishers' feet. bows, bayous, and shores of rivers and reservoirs. On the dirt floor of the nest chamber the female lays five to eight white eggs. Both sexes incubate the clutch, Population with the female sitting at night. The eggs hatch after about 24 days. The young are altricial; they have pink flesh, and Pennsylvania is veined with streams, and kingfishers are their eyes are shut. The female broods them continuously widely distributed across the state. The birds are absent from for three to four days after hatching. The adults regurgitate places such as southern Clearfield County, where acid mine fish to the young and, as the hatchlings grow and strengthen, drainage has polluted long sections of waterways. Stream begin bringing them whole fish as frequently as once every channelization destroys the vertical banks needed for nest- 20 minutes. After defecating, the young use their bills to ing. Biologists believe that breeding densities reflect the peck or scratch at the nest chamber's walls, so that dirt covers number of suitable foraging sites, especially riffles. A study up their waste. When two weeks old the young may crawl in Ohio found five pairs of kingfishers nesting along six from the nest chamber into the burrow. They leave the nest miles of river shoreline; another study in New Brunswick four weeks after hatching; the parents hold fish in their documented 10 pairs in one mile. bills, sit on a nearby perch, and coax the young into fly- ing from the entry. The adults feed the fledglings for about three weeks as the young learn how to take crayfish, aquatic insects, and fish. Parents may teach their offspring to dive by dropping insects into the water beneath the youngsters' perch. Skunks, minks, raccoons and black rat snakes kill some young in the nest; after they fledge, juveniles are vulnerable to hawks. Kingfishers escape from predators by div- ing into the water. Individuals breed dur- ing their first year after hatching. In the northern parts of its range, Ceryle alcyon raises one brood per year. After the mat- ing season, pairs break up and individuals settle on and defend smaller territories. King- fishers migrate south from mid-September until December. Most birds in the Northeast are partial migrants, able to survive winter temperatures if streams stay unfrozen, so the birds can find fish. When migrating, kingfishers tend to follow rivers, lake shores and coastlines. Wildlife Notes are available from the Pennsylvania Game Commission Bureau of Information and Education Dept. MS, 2001 Elmerton Avenue Harrisburg, PA 17110-9797 www.pgc.state.pa.us An Equal Opportunity Employer
75 Wildlife Note — 37 LDR0603 Mallard by Chuck Fergus The mallard, Anas platyrhynchos , is the most common or double-noted whistle. Mallards fly in small groups or duck in the United States, North America and the North- in V- or U-shaped flocks, usually with 10 to 20 members ern Hemisphere. It is among the best known and most but sometimes with as many as several hundred. The widely recognized of all wildlife. The species possesses mallard's broad wings and relatively short tail may cre- the largest breeding range of any bird on the continent, ate the impression that the wings are set farther back nesting across Canada and Alaska south to California, than on most ducks. Mallards are swift fliers and excel- New Mexico, Kansas, Ohio and Virginia. Taxonomists lent swimmers. They may feed and rest in the company recognize seven races. The mallard may have been the of other puddle ducks, including northern pintails and first domesticated bird, and from it have sprung all do- black ducks. mestic duck breeds except the barnyard muscovy. Mallards eat a variety of natural and human-produced The mallard is known as a "puddle" or "dabbling" duck. foods. Natural items include seeds of bulrushes, pond- This means it frequents shallow, marshy habitats, where weeds, millet, sedges, smartweed and wild rice; stems and it obtains plant and animal food on and near the water leaves of many aquatic plants; and acorns. Ducklings feed surface, feeding by dabbling with its bill in the shallows mainly on insects, particularly mosquito larvae, and also and by tipping up — hoisting its tail in the air and stretch- on crustaceans in addition to plant parts. The mallard's ing its neck and head underwater. Like all puddle ducks, bill has a serrated edge — the duck picks up food in the the mallard can spring directly into the air when taking bill, forces water out through the serrations, and ends up off; it does not have to run across the water surface to with a mouthful of edibles and grit. build up speed like diving ducks do. When natural foods are plentiful and available, mal- lards prefer them, but when ice closes up marshes, lakes Biology and ponds, they head for dry land and corn. Perhaps more than any other duck, however, mallards are notorious for Length: adult male, about 24½ inches; adult female, feeding in farm fields where they search for grain in the 23 inches. remaining stubble of corn and sorghum fields. Mallards Weight: adult male, 2¾ pounds; female, 2½ pounds. travel up to 25 miles for food. The male, or drake, is easily recognized by his dark green Often they make two feed- head, the narrow white ring around his neck, and the dark ing flights per day, one at chestnut breast. His rump is black, the outer tail feath- dawn and the other in late ers white, the underparts whitish, the sides gray, and the afternoon. back brownish. The female, or hen, has a buff-colored Mallards head and a straw-brown body streaked or mottled with mature many shades of brown. The speculum (a brightly colored sexually patch of feathers on the trailing edge of the wing and in their close to the body) is violet-blue bordered with white first year. stripes on both edges. The male's bill is yellow, his legs A period and feet are orange-red. The female's bill is orange with of social dark spots, her feet orange. display be- Mallards are among the most vocal of waterfowl. The gins in late hen makes a variety of quacks. The drake utters reedy fall and contin- quacking sounds and, during mating season, a sharp single ues through winter
76 Population into spring. Males grunt and whistle, swim, pump their heads and preen in front of the females. The hens stimu- In North America, the densest population of mallards late the courtship with calls and their own stylized body is in the northern prairies of the Great Plains (Montana, movements. Most pair-forming activities occur on the North Dakota and the Canadian provinces of water, although chase flights in spring are prominent Saskatchewan, Alberta and Manitoba), with nearly half courtship rituals. of the continent's mallards breeding there. Mallards win- Most hens have chosen their future mates by the time ter throughout most of the United States, with heavy mallards arrive on the northern breeding grounds in concentrations in the Mississippi Flyway. In the Atlan- spring. The male selects a home breeding range that he tic Flyway they concentrate in South Carolina and on defends against other mallard pairs; the female selects the Chesapeake Bay. They also winter in parts of Canada, the actual nest site. Mallards primarily nest around fresh- Alaska, Mexico and Central America. water lakes, ponds, marshes and reservoirs across Penn- Compared to most species of wildlife, the mallard sylvania, but it's not uncommon to find them nesting in population has fared relatively well during man's chang- agricultural fields and in residential areas. ing of the environment over the past century. Waste grain The hen typically nests within 100 yards of water, on left by mechanical harvesting equipment provides im- the ground in a depression lined with reeds and grasses, portant winter food, and the construction of many ponds with soft down added from her breast. She conceals the and reservoirs has created a good interspersion of water nest in tall grass, dead reeds, alfalfa or clover. A few in- and suitable land habitat for them. Mallards, more adap- dividuals nest in stumps, tree cavities or in the crotches tive than other wild ducks, quickly exploit these chances, of trees. even in suburban areas. Eggs, from 6 to 15 but usually 8 to 12, are laid one per In the Northeast, the mallard was considered a rare day. Shells are smooth, light greenish or grayish buff, migrant at the turn of the century. Today it is the region's sometimes nearly white. A hen occasionally will lay eggs most common duck. In 1969, hunters for the first time in the nests of other ducks. Incubation is by the hen alone bagged more mallards than black ducks in the Atlantic (the male deserts his mate at this time), beginning with Flyway, a trend that continues today. The black duck, the laying of the last egg so that all hatch at about the , is a close relative of the mallard, and the Anas rubripes same time. Incubation takes 23 to 29 days. two species hybridize readily. In the last several decades, Within about 12 hours of their hatching, the hen leads the black duck's population has declined. Many scien- her young to water. Mallards normally raise one brood a tists attribute the decline to, among other reasons, in- year, but if a skunk, crow, raccoon, opossum or other creased interbreeding with the mallard, and to the predator destroys her first clutch, a hen may try again. mallard's range expansion into formerly exclusive black Re-nesting attempts average fewer eggs (6 to 8). Nests duck habitats. Mallards currently comprise 50 percent are also lost to plowing, hayfield mowing and flooding. of Pennsylvania's duck harvest. In addition to the predators mentioned above, snakes, foxes, largemouth bass, muskellunge and snapping turtles Habitat also take ducklings. The young can fly after 7 to 8 weeks. After the drakes leave their mates (May to June), they Mallard breeding habitat combines shallow-water for- fly to more secluded areas where they undergo their an- aging sites and thick vegetation for nesting. The species nual eclipse molt. This replacing of feathers demands prefers open country to woodlands. Ponds, edges of fresh- considerable energy, and the birds seek out food-rich water lakes, sloughs, reservoirs and marshes are ideal. areas. A complete, simultaneous wing molt leaves them Mallards often use man-made nesting structures placed temporarily flightless; at this time they are in a drab over water. They winter on marshes, lakes, and the open "eclipse" plumage, which resembles the female's colora- waters of rivers and bays. They feed in these places and tion and provides protection against predators. Hens croplands. undergo a similar molt after their ducklings mature. The Most waterfowl moves away from areas frequented by wing feathers grow back in 2 to 3 weeks. humans, and consequently have been driven from suit- In fall and winter, mallards fly south when ice and snow able habitat by expanding towns and cities, rural devel- cover their feeding and resting areas. Among puddle opment and vacation homes. The mallard and the Canada ducks, the mallard and the closely-related black duck goose, less wary of humans, are occupying much of this are the latest fall migrants, often remaining as far north altered habitat. as open water prevails. Many of the mallards found here in the fall are from breeding grounds in Ontario, Quebec and the Lake States. The mallard is one of the earliest ducks to return north in the spring. In Pennsylvania mal- Wildlife Notes are available from the lards are common migrants in late February, March and Pennsylvania Game Commission early April. Bureau of Information and Education The life span of the mallard is 7 to 9 years, although Dept. MS, 2001 Elmerton Avenue more than half die before they reach two years of age. Harrisburg, PA 17110-9797 Ducks die from predation, accidents, hunting and dis- www.pgc.state.pa.us eases — botulism, fowl cholera, duck virus enteritis, as- An Equal Opportunity Employer pergillosis and others.
77 Wildlife Note — 41 LDR0103 Mice and Voles by Chuck Fergus They are the rarely seen multitudes, the small, unob- closed. The mother nurses them, and they grow rapidly; trusive creatures at the base of nature's food chain. Mice litters are weaned and on their own within a month, and and voles are quick, prolific breeders. In terms of biom- the mother — who has already ovulated and bred again — ass — the total mass of living matter in a given area — gives birth within a few weeks. Young from early litters can they greatly outweigh the many predators that depend reproduce during their first year. In one of the most prolific on them for food. Pennsylvania has two native species of species, the meadow vole, a female can potentially give birth mice, four voles, a bog lemming, two types of jumping to nine litters with a total of 72 offspring per year. It's not mouse, and two European immigrant species. All are ro- hard to see how quickly a population might explode were it dents, with two pairs of constantly growing, chisel-shaped not for constant attrition from predators, parasites, disease incisor teeth, one pair on the upper jaw opposing an- and accidents such as fires and floods. other pair on the lower jaw. Mice and voles mainly eat vegetation — nuts, seeds, Deer Mouse ( Peromyscus maniculatus ) — A small mouse fruits, leaves and grasses. Most species collect and hoard with a huge range (the Northeast, Midwest and the West foodstuffs to eat at a later time and to subsist on over win- from Alaska to Mexico), the deer mouse occurs through- ter. In a small way, they may prey on insects and their lar- out Pennsylvania. It is 6 - 8.5 inches long, including the vae, snails, slugs, spiders and, in some cases, birds' eggs and tail, which is three to four inches. A deer mouse weighs other mammals. In turn, mice and voles are fodder for a 0.4 - 1 ounce. For the first month of its life, an individual vast assortment of predatory animals including snakes, is colored gray; then it molts into its brownish-gray adult shrews, weasels, raccoons, skunks, bobcats, foxes, coyotes, pelt. In both juveniles and adults, the undersurfaces are pure domestic dogs and cats, and even animals as large as black white. The deer mouse has large dark eyes well adapted to bears. Many hawks and owls prey mainly on mice and voles, night vision. and the larger herons take these rodents occasionally. Deer mice inhabit nearly every type of land habitat in Mice and voles live in nearly every type of habitat, from Pennsylvania: farm fields, fencerows, grassy berms of roads, rocky slopes in forested mountains and low boggy meadows brushland and deep woods, both dry and damp, pine and to urban streets and inside peoples' houses. Some move hardwood. (Some taxonomists recognize two forms of about on the surface of the ground, while others keep to , the "woodland deer mouse" and Peromyscus maniculatus thick vegetation, rock crevices or tunnels. Most feed at night "prairie deer mouse.") Deer mice eat seeds of many plants, and remain active year-round. Only the jumping mice hi- cultivated grains, soybeans, corn, berries, buds, nuts and bernate. During bitter cold, the other mice and voles be- mushrooms. They consume beetles, grasshoppers, crickets come torpid and sleep for a time in their nests, round masses and caterpillars (including those of the gypsy moth); other of leaves and grasses whose inside chambers are lined with invertebrates such as earthworms, centipedes, slugs and spi- soft plant matter. Some species are social in winter, when ders; and carrion. small groups huddle together for warmth. Deer mice have sharp hearing and good eyesight. They The gestation period for most mice and voles is around locate most of their food by smell. They can swim if neces- three weeks. Young are born without fur and with their eyes sary and run at nearly five miles per hour for short dis- White-Footed Mouse
78 tivated fields, pastures, rhododendron thickets, tances. The tail, covered with fur, acts as a tactile organ fencerows, stream margins, ravines, revegetated strip and a balancing aid; when climbing, a deer mouse wraps mines, and in farm buildings and houses. Some authori- its tail around twigs or branches to gain steadiness. ties believe the white-footed mouse prefers a slightly drier The species weaves ball-shaped nests, 6 - 8 inches in habitat than the deer mouse. White-footed mice nest in diameter, out of leaves, grasses and other plants, lined stone walls and rock crevices, under old boards, and in with fur, feathers and shredded plant matter. Deer mice woodchuck burrows, beehives, tree cavities, and the aban- nest in hollow logs, stumps, fenceposts, beneath rocks, doned nests of squirrels and birds. Like deer mice, in root channels underground and, rather frequently, in white-footed mice do not dig burrows but use the run- abandoned squirrels' and birds' nests in trees up to 50 ways of other small mammals. They are very agile and feet above ground. Deer mice rest in their nests during can climb trees. Individual home ranges vary from 0.11 - the day, and there they rear their young. Nests at ground 0.86 acres, with males' ranges slightly larger than females'. level may have a nearby burrow with a latrine area for From 1 - 13 white-footed mice may inhabit one acre. waste and a chamber for storing food. White-footed mice eat about a third of their body In winter, if snow covers the ground, deer mice spend weight daily, or around 0.2 ounces: seeds, nuts, berries, most of their time beneath the white blanket, where the fungi, green plant matter, insects (chiefly caterpillars and temperature is warmer than in the open air. They eat stored ground beetles), centipedes, snails, and small birds and food. In extreme cold, deer mice cut down on their activ- mice. They cache food in autumn, carrying seeds in their ity, sometimes sleeping for several days, perhaps huddled in cheek pouches to chambers beneath logs and stumps. a communal nest with two to four other mice (some of which They breed from March through October; the three or may be white-footed mice, a different, although closely re- four annual litters have 3 - 7 young apiece. Females can lated, species). It's common for people to find deer mice mate when two months old. Males sometimes help fe- using bird boxes in winter. males rear the young. Deer mice breed from March to October. Females raise 3 - 4 litters per year, each with 3 - 7 young. In one year, a Meadow Vole ( Microtus pennsylvanicus ) — The meadow female can produce nearly 30 young, although few sur- vole is a stocky mouselike creature with a blunt head, beady vive long enough to do so. Young mice, called pups, ut- eyes and a short, scantily furred tail. Its upper parts are a ter high-pitched squeaking sounds. Males do not help dull chestnut brown, with a darker area along the middle of females raise the litters. Deer mice are preyed upon by the back, and its underparts are grayish or buffy white. The foxes, cats, short-tailed shrews, mink, weasels, hawks, owls meadow vole is 6 - 7.6 inches long, including a and snakes. Home ranges vary from 0.05 - 2.5 acres, with 1.3- to 2.5-inch tail; weight is 0.7 - 2.3 ounces. The spe- three to 36 mice per acre of habitat. Like most other small cies, often called a "field mouse," lives across northern mammals, deer mice are very abundant in some years and North America and is the most common vole in the East. rather scarce in others. In Pennsylvania it is abundant statewide. Meadow voles thrive in moist meadows and fields thick White-footed Mouse Peromyscus leucopus ) — Found ( with grasses and sedges. They do not live in forests but may statewide, this handsome nocturnal mouse may be the most inhabit small clearings, bogs and grassy openings in the abundant rodent in Pennsylvania. It looks much like a deer woods. They are good swimmers and can run at five miles mouse, except that its tail is shorter in relation to its body. per hour. Meadow voles move about in low, thick grass and The coat is reddish brown above, white on the belly and weeds that screen them from hawks and owls. I remember feet. Length is 6 - 7.5 inches, including a 2.5- to 3.5-inch one winter when the uncut hayfield next to a friend's house tail. Weight: 0.6 - 1 ounce. was practically swarming with meadow voles. (His dogs White-footed mice live in shrubby areas, woods, cul- spent hours digging the rodents out, pouncing, then gruesomely eating.) I was struck by the intricate net- work of surface runways visible when the grass was Meadow Vole parted: the small pathways (about the width of a garden hose) branched this way and that and were obviously much used by voles as they went about feeding on vegetation. Meadow voles eat grasses and sedges (cut stalks with seedheads are stored in small piles in the runways to be eaten later), tubers, roots, grains and the inner bark of shrubs and trees; voles sometimes girdle small trees, kill- ing them. Meadow voles are active all year, by night and by day, especially around dawn and dusk. Voles nest in shallow burrows three to four inches underground or hidden in grass. During win- ter, voles huddle together in the nests or move about and feed in runways beneath the snow. In breeding season, meadow voles vigorously defend individual territories of 0.1 - 0.8 acres, larger in sum-
79 fencerows and farmland edges; and orchards. mer and smaller during peak population years — when The woodland vole is a molelike species that burrows up to 166 voles may live on a single acre. Usually a high beneath the soil just below the leaf litter. It breaks up the population crashes to a low level, then builds up again to dirt with its head, incisors and forefeet, turns around, and another high. Females produce from 8 - 10 litters in a high shoves the dirt out the tunnel's entry, forming a cone-shaped population year and 5 - 6 litters in a year when food is pile two or three inches high. Meadow voles, hairy-tailed scarce. The average litter is 4 - 7. Among the myriad . moles and shrews use the burrows of Microtus pinetorum predators that attend to the vole population are herons, Woodland voles seldom leave their burrows, and an crows, gulls, foxes, house cats, weasels, opossums, skunks, individual's home range is small, around a hundred feet in shrews, bears, bass, pickerel and snakes. Many voles are diameter. Foods include roots, stems, leaves, seeds, fruits and snatched up by hawks and owls, particularly barn owls. In tree bark; in gardens, potatoes and flower bulbs are eaten. fact, the welfare of barn owls, short-eared owls and north- Woodland voles kill fruit trees by girdling the bark or dam- ern harriers is literally tied to the presence or absence, aging the roots. They cache food in storage chambers as deep ups and downs of this species. Maximum longevity is as 18 inches underground, and they rear their young in nests around a year and a half in the wild. under rocks, logs and stumps. Woodland voles breed less prolifically than other voles, bearing 1 - 4 litters per year, )— Southern Red-backed Vole ( Clethrionomys gapperi each with 1 - 5 young. This rodent is 4.7 - 6.2 inches long, including a 1.2- to 2-inch tail, and weighs 0.6 - 1.3 ounces. A reddish band ) — The Southern Bog Lemming ( Synaptomys cooperi down the back and a pale gray belly distinguish the spe- southern bog lemming looks much like the meadow vole, cies. A woods dweller found in much of upland Pennsyl- with chestnut brown upper parts and silver-gray sides and vania, the red-backed vole favors cool, damp forests with belly. Length is 4.5 - 5.7 inches, including a tail of 0.6 - 1 hemlocks, mossy rocks, stumps and rotten logs. It also in- inch; weight is 0.9 - 1.6 ounces. The species is found in habits deciduous and mixed woodlands with mosses and scattered pockets across Pennsylvania, mainly in old fields ferns, rocky outcrops, stone walls, reverting fields and grown up with poverty grass, timothy, broom sedge, haw- grassy clearings. When traveling, it uses the burrows of thorns, crabapples and locust. Bog lemmings live beneath moles and shrews and casts about beneath the fallen matted dead grass in surface runways created by their cut- leaves. It also climbs into low trees. The species breeds ting of and feeding on low-growing plants. They eat stems from late March through November, nesting in cavities and seeds of grasses and sedges, along with berries, fungi or appropriating abandoned nests of other species. It feeds and mosses. The species breeds from early spring to late on nuts, seeds, berries, green vegetation, roots and fungi. autumn, with 3 - 5 young per litter and several litters each year. Southern bog lemmings often share habitats with ) — This species of New Rock Vole Microtus chrotorrhinus ( red-backed voles, meadow voles, white-footed mice and England and Canada inhabits a limited area of northeastern deer mice. Pennsylvania. It closely resembles the more common meadow vole, except that the rock vole has a yellowish or- ) — The Meadow Jumping Mouse ( Zapus hudsonius ange nose. The rock vole inhabits forests. In Pennsylvania meadow jumping mouse has big feet, long hind legs, and a it lives in cool, damp woods of maple, yellow birch and hem- skinny, tapering, sparsely furred tail that is longer than lock, among boulders and lush groundcover, mainly ferns. the head and body combined. Length is 8 - 9 inches, in- Foods include green plants, seeds, leaves, stems, fungi and cluding a 5- to 6-inch tail; weight is around 0.6 ounces. insect larvae. Weasels, foxes, timber rattlesnakes and cop- Found in the East, Midwest, Canada and Alaska, Zapus perheads prey on rock voles. Females bear 2 - 3 litters is statewide in Pennsylvania. The fur is hudsonius of 1 - 7 young each year. Considered rare in Pennsylva- yellowish brown, with a dark stripe on the nia, was classified as a "vulnerable" Microtus chrotorrhinus back and orangish sides; the belly species by the Pennsylvania Biological Survey in 1985. and feet are white. ) — Also called Microtus pinetorum ( Woodland Vole the pine vole, this species is found in the Mid- west, the East and New England. In Penn- sylvania it is statewide, with the great- est numbers in the southeastern lowlands. is Microtus pinetorum Pennsylvania's smallest vole: Woodland Jumping length, 4.3 -5.5 inches; tail, 0.7 - 1 inch; weight, 0.9 - Mouse 1.3 ounces. Its soft, glossy fur is chestnut brown on the upper parts and gray on the belly. Preferred habitats include wooded bottomlands; hemlock and hardwood forests; old fields, thickets,
80 Meadow jumping mice inhabit moist grassy and brushy Wildlife Notes are available from the fields, thick vegetation and woodland edges. The home Pennsylvania Game Commission range is usually less than an acre. The name "jumping Bureau of Information and Education mouse" is something of a misnomer, as these animals do Dept. MS, 2001 Elmerton Avenue not normally travel by jumping: they prefer taking short Harrisburg, PA 17110-9797 hops of a foot or two. Active at night, they eat seeds, www.pgc.state.pa.us grasses, berries, nuts, roots, fungi, earthworms, insects, spiders and slugs. An Equal Opportunity Employer The species breeds from May to October, with two lit- ters of 3 - 6 young born yearly, in nests beneath boards, in skunks, minks, bobcats and snakes prey on woodland hollow logs, and in grass tussocks. Zapus hudsonius hiber- jumping mice. Like its cousin the meadow jumping mouse, nates in winter; in October or November, after laying on the woodland species hibernates from October to late up to 0.2 ounces of body fat, the meadow jumping mouse April or early May (about half the year) in an underground retires to a nest about 18 inches below ground. The mouse nest, singly or in pairs. Females bear 3 - 6 young in late curls into a ball, buries its nose in its belly, coils its tail June or early July; a second litter may be born in August. around itself and sleeps. Its breathing lags, its tempera- ture falls to a few degrees above freezing, and its heart Norway Rat ) — The Norway rat is Rattus norvegicus ( rate slows to a few beats per minute. After six months' 12 - 18 inches in length, including a naked, scaly suspended animation, the meadow jumping mouse 6- to 9-inch tail. Weights range from 10 ounces to more emerges in late April or early May. than a pound. This rodent's fur is thin, coarse, reddish to grayish brown above and paler below. The species arrived from Europe aboard ships around 1775. Today it is found statewide, and it ranges across North and Central America. Norway rats have poor vision, but their senses of smell, taste, hearing and touch are well developed. Extremely adaptable, they live in and under barns and farm buildings, in city sewers and dumps, along streams and rivers, and in marshes and open fields. They dig burrows about three feet long with several escape holes lightly plugged with weeds or dirt and hidden in grass or under rubbish. Rattus norvegicus lives in colonies composed of several family groups that share feeding and nesting areas. Although they're mainly noctur- nal, rats also move about and feed during the day. Rats eat anything they can find or subdue, including fish, eggs, veg- etables, grain, fruits, nuts, garden crops, carrion and garbage. They kill poultry, snakes, young rats from neighboring colo- nies, and wild birds; in local areas, rats may suppress or wipe out native birds and mammals, especially ground-nesting birds. In turn, rats are preyed on by dogs, cats, minks, snakes, and large hawks and owls. House Mouse Norway rats breed throughout the year, with peak activ- Napaeozapus insignis Woodland Jumping Mouse ( )— ity in spring and autumn; a female may bear 6 - 8 litters Found in the Northeast, New England and Canada, the per year, with an average of 6 - 9 young per litter. Rats woodland jumping mouse lives throughout Pennsylvania carry many diseases, including rabies, tularemia, typhus except for the southeastern lowlands. It is 8.4 - 9.8 inches and bubonic plague. Another introduced Old World rat, long, including a 5.5-inch tail. It has a bright yellowish the black rat ( ) used to be found in small num- Rattus rattus brown back and sides and a white belly; the tail is tipped bers in southeastern Pennsylvania, but no longer seems with a prominent white tuft. Napaeozapus insignis prefers to do so. cool, moist hemlock-hardwood forests in the mountains; it lives near streams, rarely in open fields or meadows, House Mouse ( Mus musculus ) — Like Norway and black occasionally in dry oak-and-maple woods. rats, the house mouse is an Old World species inadvertently Woodland jumping mice eat seeds, berries, nuts, green brought to North America by European settlers. It inhabits plants, fungi (particularly subterranean fungi of genus Pennsylvania statewide, living in and near houses and on Endogene) , insects, worms and millipedes. An individual farms. Six to 8 inches long, it has a 3-inch, scaly, nearly home range is 1.2 - 8 acres. Although mainly nocturnal, hairless tail; its weight is ½ - 1 ounce. House mice come woodland jumping mice venture out on cloudy days. They in various shades of gray. Omniverous, they eat every- use burrows and trails made by moles and shrews. Nor- thing from grain and seeds (their preferred foods) to pa- mally they travel on all four feet, but for greater speed per, glue and household soap. is agile and Mus musculus they hop with their long hind legs and can leap up to 10 quick, able to run at eight miles per hour. An adult fe- feet. They evade predators by taking several bounds, then male produces 5 - 8 litters annually, each with an aver- stopping suddenly under cover. Screech owls, weasels, age of 5 – 7 young. The species is active the year around.
81 Wildlife Note — 22 LDR0103 Minks and Muskrats by Chuck Fergus Often two wildlife species are associated closely with Mink have excellent hearing and sight, and a good each other. The fox and the rabbit, the bobcat and the sense of smell. On land, they travel at a slow, arch-backed snowshoe hare, and the mink and the muskrat are good walk or a bounding lope, which they can keep up for examples. While not one of the three mentioned preda- miles. They swim and dive with ease; a webbing of stiff tors subsists solely on its "partner" species, the prey of- hairs between the toes of their hind feet helps propel ten makes up a sizeable portion of the predator's diet. them through water. Mink are most active at night and When it comes to mink and muskrats, it's fair to say that early morning, although they sometimes venture out although the muskrat is not the principal prey of the mink, during the day as well. the mink is the principal predator of the muskrat. Active year-round, mink may curl up and sleep for Both mink and muskrats are found in suitable wet- several days during winter cold spells. Like most land habitat throughout Pennsylvania. They are classi- mustelids, they are agile and fierce fighters, killing prey fied as furbearers, and trappers harvest both species. By with a hard bite to the far, more muskrats are trapped than minks, but a mink back of the skull. pelt is more valuable than a muskrat's. Prey includes musk- rats, mice, rabbits, Mustela vison) Mink — is a semi-aquatic member of ( shrews, fish, frogs, the family Mustelidae. Other mustelids include weasels, crayfish, insects, martens, fishers, wolverines, badgers, skunks and otters. snakes, water- Mink are found over most of the northern hemisphere in fowl and other both Europe and North America. They live on the edges birds, eggs and of lakes, streams and rivers in forested areas. domestic poul- Adult males average two feet in length, including an try. Generally, a 8-inch tail. They weigh 1½ to 2 pounds. Females are 10 mink is an oppor- to 15 percent smaller than males and up to half a pound tunist, feeding on lighter. Body configuration resembles that of a weasel: whatever is most short legs; long, bushy tail; long, sinuous neck and body; easily caught or short head; and pointed muzzle. A mink's coat is thick, found; thus, it might full and soft. A short, tight layer of underfur is covered avoid fighting to kill a with longer guard hairs, which give the pelt its luster. healthy adult muskrat Colors range from russet to a deep, chocolate brown. if, say, crayfish were Unlike some weasels, the mink does not turn white in abundant and easily cap- winter. tured. Mink occasionally kill
82 and rats. The nation's most abundant furbearer, the musk- more than they can eat. In winter, they cache carcasses rat lives on or near the still or slow-moving water of and revisit them to feed. ponds, marshes, streams and rivers and, to a lesser ex- Mink den in abandoned woodchuck tunnels, hollow tent, faster mountain streams. The species is found over logs, vacant muskrat lodges, holes in stone piles and be- most of North America north of the Rio Grande River, neath large tree roots. Dens are usually near water and including the coastal tidal marshes. It's common in Penn- may have more than one entrance. Mink line their nests sylvania, but nearly abundant as it used to be. with dried grass, leaves and feathers; bones and scraps of Adult muskrats are 22 to 25 inches in length, includ- kills often litter the nest area. ing the tail. They weigh 2 to 3 pounds, have a stout body, Mink are basically solitary, except during mating sea- short legs, and an 8- to 12-inch tail that is flattened ver- son, when they use a powerful scent from their anal glands tically, scaly and practically hairless. Ears and eyes are to attract mates. Males fight over receptive females. It's small but well-developed. In appearance, muskrats re- not known whether mink pair up after mating, although semble small beavers with long, rat- males are believed to mate with several females. like tails. Mating occurs from February to April, with most ac- The tail functions as a prop tivity in March. After mating, the fertilized eggs develop when the animal stands on its hind slightly, but then 13 to 50 days may pass before the em- feet, and as a rudder and propul- bryos attach to the female's uterine wall and continue sion-aid when it swims. The developing. This is called delayed implantation, and it's muskrat's large, broad, partially common among mustelids. Females give birth in webbed hind feet power it early May following a gestation period of through water. Its forefeet are 28 to 30 days after embryo implan- small and agile, with well-de- tation. Thus, total time from mat- veloped claws for burrow- ing to birth may be 40 to 80 ing. To insulate against days. cold water, a muskrat's At birth, young are 3½ underfur is dense, silky inches in length, blind and soft, overlain with and hairless, and they long, dark brown guard weigh only a fifth of an hairs shading to gray- ounce. Litters include brown on the throat 2 to 7 young, with an and belly. Overall pelt average of four. In two color can be chestnut- weeks, young are brown to almost furred; their eyes open black, or any color after five weeks; and after in between. six or seven weeks they are Food: roots and out foraging with their mother stems of aquatic plants and learning how to hunt. The family dis- (the cattail is often an important item; also bullrushes, perses by late summer. Minks are sexually mature at 10 water lilies, pickerelweed and others), and, when they months. grow near water, legumes, grasses, grains, garden crops Minks are best suited for areas where water pollution and fruits. Muskrats eat a small amount of animal pro- is minimal, because these waters will hold the greatest tein, including crayfish, freshwater mussels, fish and frogs concentrations and varieties of prey. A male covers a — the last two often as carrion — and even carcasses of range up to three miles in diameter, while a female's range other muskrats. They don't hibernate; over winter they is much less. Individual territories overlap, and the same subsist on roots and shoots dug from marsh bottoms, and den may be used by several animals in succession. One the twigs, buds and bark of various trees, including wil- mink will have several dens along its hunting route. lows, cottonwoods, ash and box elders. Minks live up to 10 years in captivity, but a wild one Muskrats build houses (also called lodges) of vegeta- would be fortunate to survive two or three winters. Dis- tion, or they burrow into stream banks, earthen dikes and ease, cars and trapping are mortality factors, and the spe- dams, often causing considerable damage. Both lodges cies is preyed on by foxes, bobcats and great horned owls. and burrows have underwater entrances and above-wa- The American mink was introduced to Sweden in the ter living quarters. Lodges are built of cattail stalks or 1920s, and in 35 years spread throughout that country. other vegetation, chinked with mud and weeds above M. Iutreola, the European mink, is found from France the waterline. They may be 8 to 10 feet across and 2 to 3 east to the Caucasus Mountains. Pennsylvania has two feet above water, with a single living chamber plus off- subspecies of mink, the less common mountain race, shoots, or several chambers. Muskrats do not dam Mustela vison vison, being somewhat smaller and darker. streams. In breeding season, muskrats leave musk, or scent, in ) — Why the name Muskrats ( Ondatra zibethica likely places around their territories to attract potential "muskrat?" "Musk" refers to a strong smelling substance mates. Males may impregnate several females, and play released from this animal's perineal glands (between the no part in raising young. thighs), while "rat" describes its rat-like appearance. The Muskrats have a high reproductive potential, giving muskrat is a rodent — related to mice, voles, beavers
83 muskrats are strongly territorial, and predation by mink birth to large litters and breeding from spring to fall. is just a way of reducing the excess population. Mink sel- Mature females have two, three or even four litters each dom have much effect on local muskrat populations; the year, depending on the length of the warm season (more surplus animals would probably die soon anyway. Only if litters in southern Pennsylvania, fewer in the north). the habitat should change, such as when drought comes After a 30-day gestation period, the female bears 5 to and the marsh dries up, would formerly secure muskrats 8 naked, blind and helpless young. In a month they are be vulnerable to minks; the habitat can no longer sup- weaned and fully furred, and the female drives them off, port as large a muskrat population, some of the basic popu- especially if she is about to bear another litter. A female lation would become surplus. A bad winter, may overwinter with her final lit- an outbreak of disease such as coccidi- ter of the year, the family break- osis, or a flood during the height of ing up in the spring. Young dis- breeding season may also cut musk- perse along streams or colonize rat numbers. The population varies new sections of marsh. widely from year to year, but tends Muskrats are sexually ma- to show a peak in abundance ture the year following their about every 10 years. birth, but few survive long Muskrats are tenacious fight- enough to breed. Young musk- ers. Minks prefer to tackle young rats and dispersing immatures or sick muskrats, because a ma- are especially vulnerable to ture adult puts up a brisk defense. minks, hawks, owls, foxes, snap- Females defending young have ping turtles and snakes. Surplus been observed driving off attack- animals — individuals beyond ing minks. Muskrats are parasit- the number that the habitat can ized by mites, fleas, flatworms, support in good health over roundworms and tapeworms. winter — are often lost to While the average life span is un- predators, taken by trappers or der 12 months, some individuals may forced to move to new areas. live as long as five or six years. Surplus individuals are more Through their feeding, muskrats open up vulnerable to predation, starva- areas of densely vegetated marsh; this can change tion and disease than are mem- local habitats to benefit waterfowl and other aquatic bers of the secure, basic popula- wildlife. Muskrats also damage agricultural and orna- tion. mental crops near water, and their tunnels riddle dams, Some prey populations may limit their own dikes, canal banks, etc. This is a serious problem and trap- numbers by failing to breed in crowded conditions, by ping is the most effective and least expensive solution to aggressively defending a territory in overpopulated ar- it. eas, or by some other type of behavior. Overcrowded Wildlife Notes are available from the Pennsylvania Game Commission Bureau of Information and Education Dept. MS, 2001 Elmerton Avenue Harrisburg, PA 17110-9797 www.pgc.state.pa.us An Equal Opportunity Employer
85 Wildlife Note — 54 LDR0103 Northern Northern Cardinal Cardinal, Grosbeaks, Indigo Bunting and Dickcissel by Chuck Fergus Cardinals live in thickets, hedgerows, brushy fields, swamps, gardens and towns and cities. They need dense shrubs for nesting; these can range from multiflora rose tangles sprawling between woodlots and fields, to hedges Cardinals, grosbeaks and indigo buntings are equipped of privet and honeysuckle on shady streets. Hawthorns, with stout, strong bills to crush seeds. In addition to seeds lilac, gray dogwood and dense conifers also provide nest- and fruit (important fall, winter and spring foods), these ing cover. Mated pairs of cardinals use territories of three birds eat protein-rich insects in summer and feed them to 10 acres. Cardinals eat caterpillars, grasshoppers, to their young. They are attracted to thick cover includ- beetles, bugs, ants, flies and many other insects; fruits of ing forests, woods edges, brushland, swamps and orna- dogwood, mulberry and wild grape; and seeds of smart- mental plantings in suburbs and cities. The dickcissel is weeds and sedges, grains scattered by harvesting equip- a related species that breeds mainly in the Midwest but ment, and sunflower seeds at birdfeeders. Cardinals are also nests in grassy habitats in Pennsylvania. not particularly fearful of humans. One day a cardinal landed on a log about three feet from where I was. It fu- Northern Cardinal ( Cardinalis cardinalis ) — Adults riously crushed a black beetle between its mandibles, dis- are eight to nine inches long, slightly smaller than a robin. carded with a shake of its head the beetle's wing sheaths Both sexes have an orange-red bill and a prominent head and spiny legs, swallowed the beetle, defecated and flew crest. The male's plumage is an overall bright red; the off: not just a flash of pretty color, I found myself think- female is yellowish brown with red tints on her wings, ing, but a fearsome predator in its own right. tail and crest. The cardinal is a common bird in the South- eastern United States. Before 1900, the species was rare Cardinals begin calling in February and March, sig- in Pennsylvania, but over the last century cardinals have naling the onset of the breeding season. Males and fe- spread as far north as Maine and southern Canada. They males sing equally well. The song is a series of clear now inhabit all of the Keystone State, except for areas of whistled notes, whoit whoit whoit (like a kid learning to unbroken forest on the Allegheny High Plateau. Cardi- whistle) or . Cardinals often countersing: wacheer wacheer nals also breed across the Midwest and in Central males on adjacent territories, or pairs within their own America from Mexico to Guatemala. They are territory, alternately match songs. As a part of courtship, year-round residents throughout their range. the male will pick up a bit of food (such as a sunflower
86 kernel at a feeder) in his bill head, a massive ivory-colored bill ("grosbeak" means Northern and sidle up to his mate; the "big beak"), white patches on black wings that flash like Cardinal two touch beaks as she accepts semaphore signals when the bird flies, and a triangular the morsel. It takes the female bright red patch on the white breast. (The patch varies three to nine days to build the somewhat in size and shape from one individual to the nest, a loose cup woven out of next.) The female looks like a gargantuan brown spar- twigs, vines, leaves, bark row. The song, given by both sexes, is robin-like but strips and rootlets, lined quicker, mellower, and full of life. Adults are about eight with fine grasses or hair. inches long. Nests, rarely higher than Rose-breasted grosbeaks breed from Nova Scotia to six feet, are often placed in western Canada and south in the Appalachians to Geor- the thickest, thorniest scrub on gia. The species is found statewide in Pennsylvania: scarce the pair's territory. in the developed and agricultural southeast, abundant The female lays two to five across the northern tier. Grosbeaks favor second-growth eggs (commonly three or four), deciduous or mixed woods and can also be found in old which are whitish and marked with orchards, parklands and suburban plantings. They eat brown, lavender and gray. She does insects (about half the diet in summer), seeds (easily most of the incubating, and the male brings her food. crushed by that formidable bill), tree buds and flowers Young hatch after about 12 days. Their parents feed them and fruits. regurgitated insects at first, then whole insects. The young Males arrive on the breeding grounds in April and fledge after 10 days; the male may continue to feed them May, about a week ahead of the females. Males sing to for a few days while the female builds another nest and proclaim a two- to three-acre breeding territory and may begins a second clutch. Cardinals can produce up to four attack other males who intrude. When courting a female, broods per year. Nest predators include snakes, crows, the male takes a low perch or lands on the ground, then blue jays, house wrens, squirrels, chipmunks and domes- droops his wings and quivers them, spreads and lowers tic cats. Brown-headed cowbirds often lay their eggs in his tail, and slowly rotates his body from side to side while cardinal nests, and the cardinals rear the cowbird nest- singing. Rose-breasted grosbeaks often nest in thickets lings. Cardinals compete with gray catbirds for food and along the edges of roads, streams or swamps. The nest, nest sites; catbirds usually dominate in these interactions built mostly by the female, is loose, bulky and made al- and may force cardinals to the fringe of usable habitat. most entirely of twigs. It is usually 10 to 15 feet above In fall the pair bond weakens between male and fe- the ground in a small tree or shrub. Since both members male. They stay together, however, and may join with is chink of the pair do much calling (a short, metallic other cardinals to form feeding groups that usually num- often given) and singing in the vicinity, the nest is fairly ber 6 to 20 birds. In winter, white-footed mice sometimes easy to find. move into old cardinal nests, stuff the cups with plant The three to five eggs (typically four) are pale green- matter, and set up housekeeping. Cardinals are preyed ish blue, blotched with browns and purples. Both par- on by hawks and owls, as well as foxes and other ground ents share in incubating them, and the eggs hatch after predators. The longevity record is 15 years. about two weeks. Both parents feed the young, which Cardinal populations rose steadily in Pennsylvania leave the nest 9 to 12 days after hatching. Should a fe- th through the 20 male start a second brood, century. Several factors may she may leave the have helped over- Cardinalis cardinalis Rose-breasted young while they're spread the state during that period: still in the nestling an increase in edge habitats caused Grosbeak phase; the male as- by rural development; a period sumes care of the first of warm winters in the early offspring while the l900s; a similar warming trend female starts building in recent years; and an in- a second nest, often crease in backyard feeding sta- less than 30 feet away tions dispensing high-energy from the first. Adults seeds that help cardinals and molt in August, and other birds survive frigid the male's new plum- weather. age includes brown and black streaks on Rose-breasted Grosbeak the head, neck and )— ( Pheucticus ludovicianus back. In September Some outdoor enthusiasts be- rose-breasted gros- lieve that no thrush can hold beaks start the migra- a candle to the rich singing of tory trek southward to the rose-breasted grosbeak, wintering grounds in and that the latter is perhaps Central and South the handsomest bird in the America. woods. The male has a black
87 The male spends much time singing from prominent Blue Grosbeak ) — Like the cardi- ( Guiraca caerulea places, and little time helping with brood-rearing. The nal, this is a southern species that has expanded north- female builds a neat cup-shaped nest out of leaves, dried ward over the last century. In the 1980s blue grosbeaks grasses, bark strips and other plant materials, one and a were found nesting in southern Fulton, Lancaster and half to 10 feet up (usually no higher than three feet) in a Chester counties and along the border of Delaware and dense shrub or a low tree, often an aspen. She lays three Philadelphia counties near the Tinicum National Envi- to four eggs, which are white or bluish white and un- ronmental Center. Males are a deep dusky blue; females marked. She incubates the clutch for 12 to 13 days, until are brown and sparrow-like. Blue grosbeaks inhabit open the eggs hatch over a one- to two-day period. Some ob- areas with scattered trees, fencerows, roadside thickets, servers report that the male helps feed nestlings, while reverting fields, brush and forest edges. They often feed others say that he does not or that he gives food to the on the ground and eat many insects, as well as the seeds female who then carries it to the nest. Sometimes a male of weeds, grasses and other plants. Breeding males sing will have more than one mate nesting in his territory. from treetops and utility wires. The female builds the nest, Young indigo buntings leave the nest 10 to 12 days after a compact open cup, three to 10 feet above the ground, hatching. In some cases, males take over the feeding of in a shrub, tree or vine tangle. The usual brood is four. newly fledged young while females start a second brood. Cowbirds often parasitize this species. Blue grosbeaks Males keep singing well into August. Most pairs raise two winter mainly in Mexico and Central America. broods. Brown-headed cowbirds often parasitize the nests, and various predators — particularly the blue jay — eat Passerina cyanea ) — The indigo bunting Indigo Bunting ( eggs and nestlings. Some researchers believe that only 30 breeds throughout the East and in parts of the Midwest and to 50 percent of indigo bunting nests are successful. Southwest. The species is statewide and common in Pennsyl- The adults molt in August. The male in his winter plum- vania. Adults are about five and a half inches long, slightly age looks much like the female, but he still has blue streaks smaller than a house sparrow. The male is bright blue, al- in his wings and tail. Buntings migrate south from late though he may look almost August through October. Many individuals cross the Gulf black in deep shade; the of Mexico, reversing their spring passage. Indigo buntings female is drab like a winter in loose flocks in southern Florida, Central sparrow. Indigo bun- Indigo America, and northern South America. The longevity tings find food on the record is 10 years. ground and in low Bunting bushes. They eat Dickcissel ) — The dickcissel is a bird Spiza americana ( many insects, includ- of the prairies and a common resident of the Midwest. A ing beetles, caterpillars rare breeding species in Pennsylvania, it has recently been and grasshoppers, found nesting in Clarion, Westmoreland, Somerset, supplemented with Fayette, Franklin and York counties, mainly on reclaimed grass and weed strip-mine sites, but also on cut hayfields, especially in seeds, grains years when drought stunts the regrowth of grasses. Nests and wild fruits. are on or near the ground, hidden in dense grass, weeds or Males mi- a shrub. grate north in late April and May, with older males pre- Dickcissel ceding younger ones and returning to their territories of past years. The two- to six-acre territories are in brushy fields, clearings in woods, woods edges and along roadsides and powerline rights-of-way. Males make moth-like display flights along territorial boundaries, flying slowly with their wings fanned and tail and head held up, using rapid, shal- low wingbeats while sounding a bubbly song. They also perch and broadcast a more complicated territorial/court- ship song, a series of high, whistled notes described as . Females, by con- sweet-sweet-chew-chew-seer-seer-sweet trast, are so shy and retiring that it's often hard to deter- mine when they've arrived on the breeding range.
89 Wildlife Note — 25 LDR0103 Opossum by Chuck Fergus The opossum, Didelphis virginiana , is one of the world's fur and skin color may vary among different geographic oldest species of mammal, and the only marsupial on our areas. continent. Marsupials are born before they are well de- Opossums walk with an ungainly shuffle, averaging 0.7 veloped, compared to other mammals, and continue their mph; their running speed is a little over 4 mph. Excel- growth and development in a pouch on their mother's lent climbers, they ascend hand-over-hand, using their abdomen. Most members of the order Marsupialia are prehensile tails for gripping and balancing. They are good, native to Australia and South America. Structurally, they but slow, swimmers. have changed little for millions of years; the opossum's An opossum's brain is small and of primitive struc- relatives date back to the Cretaceous Period, 90 million ture. Senses of smell and touch are well developed, but years ago. However, the opossum didn't appear in North hearing is not especially keen and eyesight is weak. When America until the Pleistocene Epoch, less than a million walking, an opossum sniffs the air and occasionally stops years ago. and stands on its hind feet to look around. Although "Opossum" is derived from the Algonquin Indian word normally silent, it may growl, hiss or click its teeth when , meaning "white animal." A creature without spe- apasum annoyed. cialized body structure or food preference, the opossum If an opossum is threatened and cannot climb a tree thrives in many settings. It is found throughout Pennsyl- or hide in rocks or brush, it may crouch and defend it- vania, and it is classified as a furbearer. self — or, if struck, may feign death. When feigning death, also called "playing possum," Biology an individual lies limp and motionless, usually on its side. Its eyes and mouth remain open, its tongue protrudes, its Mature opossums are 24-40 inches long, including a forefeet clench, and its breathing becomes shallow. This 10- to 12-inch tail. They weigh 4-12 pounds. Males are state may last from a few minutes to several hours. Feign- larger and heavier than females, and the average adult is ing may help an opossum survive an attack, because some about the size of a large house cat. predators ignore dead prey. Opossums also exude a musky An opossum has a long, pointed snout with 50 odor that may repel some enemies. teeth — more than any other North American Wildlife biologists have yet to mammal — small, dark eyes and rounded, bare determine whether feigning ears. The tapering tail is naked and scaly, death is deliberate (a be- like a Norway rat's. Their feet have five havior evolved for sur- toes, each with a claw, except the vival) or involun- first toe of each hind foot, which is long and capable of grasp- ing, like a thumb. Their long, coarse body fur is light gray; outer hairs may be tipped yellow-brown. Legs and feet are dark brown or black. Males, females and immatures are col- ored alike, although
90 their ears and tails to frostbite. tary (perhaps caused by nervous paralysis). Ticks, fleas, cestodes and nematodes parasitize opos- Opossums are omnivorous and opportunistic — they sums, and the species is preyed on by foxes, bobcats, eat whatever they can find. Animal food includes terres- hawks and owls. Trappers also take some. Many opos- trial and aquatic invertebrates (mainly insects), lizards, sums are killed by vehicles while feeding on other high- snakes, toads, the young of small mammals, bird eggs and way-killed animals. An opossum's life expectancy in the young birds. Plant foods include berries (grapes, poke- wild is about 1½ years, with a few reaching age 5. berries, blackberries, etc.), mushrooms, acorns, cultivated plants. Opossums eat more animal than plant food. They Population consume garbage and carrion, including animals killed on highways. Sometimes opossums forage by day, but they The opossum is common in wooded areas throughout are mostly nocturnal. They take shelter in hollow logs, Pennsylvania. On a continental scale, it ranges from woodchuck burrows, rock crevices, tree cavities, the aban- southeastern Canada south through New England to doned leaf nests of squirrels and beneath porches and old buildings. They seldom spend two successive nights Florida, west to Minnesota, Nebraska and Texas, and in the same den. Opossums do not dig their burrows, but south to middle America. It has been introduced in sev- they will occupy abandoned burrows. eral western states. Opossums are solitary. Females and unweaned off- Opossums are unspecialized animals that can utilize a variety of foods and habitats. The species has expanded spring stay together, and the sexes come in contact dur- its range north and west during the past century. Their ing breeding season, late February and March in Penn- population is stable. sylvania. After mating, the female drives off the male. The male plays no part in raising young. Habitat The opossum's gestation is short — 12 or 13 days. New- born young are hairless, pink-skinned, blind and scarcely Opossums are at home in farmland and woodlots, re- past the embryonic stage. They are about one-half inch verting fields, brushy woods, open woods, in dry or wet in length and weigh 0.005 ounces. Hind limbs are rudi- terrain and at varying elevations. They inhabit suburbs mentary, but the front limbs and feet are well-developed and the edges of towns where food and cover are avail- and equipped with claws. The young crawl upward, with able. Ideal habitat is bottomland woods surrounding overhand strokes as if swimming, through the mother's streams. fur to a pouch in the skin of her belly. An opossum's range depends on food availability and Most litters vary from 5-13 young, averaging 8 (as the individual's tendency to wander. In one study, biolo- many as 21 have been reported). The pouch is lined with gists found that opossums had elongated, rather than cir- fur and contains mammary glands. When a young opos- cular ranges (circular being the pattern of most other sum attaches and begins to nurse, the nipple enlarges, land-based wildlife), following the edges of rivers and forming a bulb on the end which swells in the baby's streams. The average home range was 0.6 miles, the study mouth and helps it stay attached. The female usually has determined. 13 mammary glands, so offspring in excess of this num- Where food is plentiful, an opossum may range only a ber die. The mother can close her pouch to keep the few hundred yards; in intensely cultivated areas, where young from falling out. fencerows, rocky field corners and reverting fields have Young grow rapidly, increasing their weight 10 times been cleared for crops, an opossum would have to range and doubling their length in 7 to 10 days. By seven weeks, farther (up to two miles) to find food. they are 2¾ inches long. After eight to nine weeks, their Habitat management aimed at helping other wildlife eyes open, and they let go of the mammary glands for the often benefits opossums. Forest thinning and edge plant- first time. They begin leaving the pouch for short peri- ing stimulate the growth of low, food-producing plants ods, riding atop their mother's back, gripping her fur with (blackberries, wild grapes, etc.) and create thick cover their claws. for escape or daytime loafing. When managing a woodlot, When three to four months old, young opossums be- sparing old wolf trees (wide-spreading trees with little gin to look for their own food and care for themselves. timber value) preserves the hollow limbs used by opos- Soon they stop nursing, but they may stay with the fe- sums. Well-managed game habitat — such as a state game male a few weeks longer. Six to nine young usually sur- land — provides many wildlife species ample food and vive to fend for themselves. cover. Females may bear a second litter, breeding again from mid-May to early July. At least two weeks pass between weaning of the first litter and birth of the second, as the female is not sexually receptive while still nursing. Fe- males can breed when they are a year old. Wildlife Notes are available from the In fall and winter, opossums devote almost twice as Pennsylvania Game Commission much time to feeding and improving their nests as they Bureau of Information and Education do the rest of the year. Opossums do not hibernate, but Dept. MS, 2001 Elmerton Avenue may den up during cold or snowy periods. Although they Harrisburg, PA 17110-9797 add a layer of fat, they do not grow a winter pelt, and www.pgc.state.pa.us their fur is poor insulation. Pennsylvania is near the spe- cies' northern limit, and many opossums lose the tips of An Equal Opportunity Employer
91 Wildlife Note — 8 LDR0103 Owls Saw-whet Owl by Chuck Fergus Owls are birds of prey, occupying by night the hunt- sounds well below the threshold of human hearing; even ing and feeding niches hawks hold by day. Superb, spe- in complete darkness a barn owl can catch prey by using cialized predators, owls are adapted to find, catch and just its hearing. The conspicuous "ears" or "horns" of great kill prey quickly and efficiently. And they've been doing horned, long-eared and screech owls are really tufts of it for ages; owl fossils found in midwestern United States feathers that have little effect on their hearing. date back about 60 million years. Eight species of owls The leading parts of a night hunter's wings — which either live in Pennsylvania or visit the state in winter. cut the air when the bird flies — have soft, serrated edges. Barn, screech, great horned, barred and long-eared owls These soft leading edges, lightweight wings and a large are permanent residents; the short-eared owl is basically wing surface area let an owl fly and glide in total silence. a winter resident, here from November to April; the saw- As its flight is noiseless, an owl easily hears other sounds whet owl is a rare resident, seen most often from Novem- while hunting. It descends to its target in a silent, moth- ber to February; and the snowy owl is occasionally spot- like glide. ted in winter, especially in Pennsylvania's northern coun- An owl grips and kills prey with its talons. Two of these ties. strong, sharp claws branch off the front toes of the foot, Taxonomists divide owls (order Strigiformes) into two and two off the back toes. If the prey is small enough, the families, Tytonidae — barn owls — and Strigidae, the owl swallows it whole; otherwise it holds the kill with its family to which all other Pennsylvania owls belong. Our talons and tears the carcass apart with its hooked beak. barn owl ranges over most of the world, with related spe- The owl's stomach absorbs nutritious portions and forms cies in South America, Europe, Africa, Asia and Austra- indigestible matter (hair, feathers, bones, claws, insect lia. Strigidae have near-worldwide distribution, includ- chitin) into round pellets which are regurgitated about ing most Pacific islands and the arctic. seven hours later. The plumage of owls is dense and soft, making them Pellets, also called castings, can be found under day- look heavier than they actually are. Their drab-colored time roosts or nighttime feeding stations. Generally, the feathers blend into the background of shaded daytime larger the owl, the larger its pellets. Pellets can be bro- roosts and the darkness of night; the feathers on owls' ken apart and the hard bony parts separated from the fur legs provide insulation and protect against bites by prey. and feathers. Close examination of the hard items gives Both sexes are colored essentially alike, but females are insight into the owl's diet. usually larger and heavier than males of the same spe- Most owls call to attract members of the opposite sex cies. during mating season and to announce individual terri- Some unusual and highly effective adaptations help tory. They also call softly for short-range communica- owls survive. Extremely large retinas make their vision tion between mates or between parents and offspring. 50 to 100 times more efficient than human sight at dis- When cornered or frightened, owls hiss or make clicking tinguishing small objects in dull light. Also, the retinas noises by snapping their mandibles (upper and lower parts are packed with rods (light-gathering cells). An owl can't of the bill). distinguish colors well, but it possesses binocular vision: Owls don't build nests. Instead, they take over aban- each eye views the same scene from a slightly different doned crow or hawk nests or use holes in trees or banks. angle, thus improving depth perception. Eyes are fixed They may add lining material to existing nests. Owls are in the skull; to look to the side, an owl moves its head, early nesters, some even lay eggs in late winter; by the and some species can twist their necks over 270 de- time fledglings leave the nest, offspring of other wildlife grees — almost all the way around. abound and are fairly easy prey for the inexperienced An owl's head is large and broad to accomodate two young owls. widely spaced and highly developed ears. Owls hear Owl eggs are round, white and undecorated, usually
92 Short-eared Snowy Owl Owl Barn Owl Screech Owl 3-5 in number. Incubation is generally the female's re- males up to 20. Both sexes have whitish or pale cinna- sponsibility, while the male hunts and brings food to the mon underparts and buffy or rusty upper plumage. female. After the eggs hatch, both female and male feed A barn owl has neither of two characteristics often the young. associated with owls: "horns" or hooting-type calls. Its Nestlings wear thick white or light gray down. Young calls include a long, drawn-out whistle, loud hisses and found in the same nest are invariably of different sizes, snores. because incubation starts as soon as the female lays the Barn owls nest in barns, hollow trees, old buildings, first egg (unlike most other birds, which begin incubat- silos, ventilating shafts and church towers. They do not ing only after all eggs are laid), and therefore this egg build nests, although castings may form a base for the hatches first. As much as two weeks may pass between eggs. They usually nest in March, April or May and lay the laying and hatching of the first and last eggs. Young from 3-11 eggs (generally 5-7) at 2- to 3-day intervals. hatched latest will die if the parents cannot find enough Incubation takes about 33 days. food in the area around the nest, as they can't compete After the eggs hatch, both parents feed the young. with the larger, older nestlings. This natural check bal- Nestling barn owls can eat their weight in food every ances predator population with food supply and ensures night. Young leave the nest at 9-12 weeks, after flight that surviving fledglings are strong. feathers develop. During the day, most owls stay in hollow trees or dark, Barn owls hunt open fields, flying low over the ground dense stands of vegetation. They hunt mainly at night — in search of prey. Ornithologists studied 200 disgorged occasionally at dusk or on cloudy days — quartering the pellets from a pair of barn owls that nested in a tower of ground in silent flight or scanning it from a convenient the Smithsonian Institution Building in Washington, D.C. perch. The pellets contained 444 skulls, including those of 225 Owls generally kill what's easiest to catch or find. As meadow mice, 179 house mice, 20 rats and 20 shrews — with most predators, they are blamed for killing more all caught in the city. Other studies have confirmed mice game and poultry than they actually do. In reality, they and shrews as this owl's main prey items. Small birds, in- are beneficial birds that prey on many pest species. Mice sects, flying squirrels and rabbits occasionally are taken. and rats form a major part of the larger owls' diets; smaller owls eat small mammals and insects. All Pennsylvania Great Horned Owl owls are protected by the Game Law and federal regula- This large owl is sometimes called the tiger of the air; tions. it is our fiercest, most powerful owl. It weighs up to 3½ pounds, is 20-23 inches in length and has a wingspan of Barn Owl nearly five feet. Females are slightly larger than males. A The barn owl is a long-legged, light-colored bird with great horned owl has soft brown plumage above, mottled a white, heart-shaped face. It is sometimes called the with grayish-white; undersides of light gray barred with monkey-faced owl. A barn owl is 15-20 inches in length dark; a "collar" of white feathers on the upper breast; a with a 44-inch wingspan; females weigh about 24 ounces, rust-colored face; and prominent ear tufts, the so-called
93 Saw-whet Owl Barred Owl Great-horned Owl Long-eared Owl horns, up to two inches long. is scarce on the arctic tundra, large numbers may migrate The great horned is known as the hoot owl for its call, south. Population crashes of lemmings and hares — and hoo- 3-8 (usually 5) deep, booming, uninflected hoots: the accompanying owl migrations — usually occur at 4- . These owls hoot to stake out territory and as hoohoo hoo or 5-year intervals. Immatures, which are darker in color, part of the species' mating activity, which in Pennsylva- go farther south than the adults. nia takes place in December or early January. Plumage of the snowy owl is white barred with grayish- Great horned owls are believed to mate for life. They brown; its feet and legs are heavily feathered. Full, soft nest in crow, heron or hawk nests, tree cavities or hollow feathering keeps the bird warm during periods of inactiv- stumps and are the earliest nesters of all owls. A mated ity between winter hunting forays. pair cleans debris from an appropriated nest, and the fe- The snowy owl is as large as the great horned owl, with male then partly lines a central hollow with feathers. She a 24-inch body length, 60-inch wingspan and body weight lays two or three eggs at several-day intervals, usually in up to five pounds. It is a bird of open fields — not wood- February, and may temporarily get covered with snow lands — which resemble its tundra home. It often perches while incubating. on a fencepost to look for mice, ground squirrels, rats, Horned owls, especially incubating or brooding pairs, rabbits and hares. The snowy owl is crepuscular (most defend nests and young viciously and have even attacked active in twilight) but is forced to hunt in the day during humans who got too close. Eggs hatch in about a month; the long arctic summer, when darkness is almost non-ex- nestlings are downy-white, weak and blind. The young istent. In Pennsylvania, the snowy owl continues these cannot fly until they're almost three months old and con- habits and often hunts during the day. It does not call tour feathers have grown. south of its arctic breeding grounds. Great horned owls prey on rabbits, wood rats, mice, birds, hares, domestic poultry, grouse, squirrels, smaller Barred Owl owls, foxes, skunks (this species' defensive spray does not The barred owl is a large bird of the deep woods. It has deter the great horned owl), domestic cats, weasels, musk- a rounded head, no horns and brown eyes (it's the only rats — in short, most animals other than the large mam- brown-eyed Pennsylvania owl except the barn owl; all mals. others have yellow eyes). The barred owl ranges over the Favored habitats are heavily forested land, large eastern United States, its distribution often coinciding woodlots and remote wilderness areas; the species ranges with that of the red-shouldered hawk. over much of North America. Horned owls aren't often A barred owl weighs up to two pounds, with a 44-inch found in populated areas, apparently needing solitude for wingspan and body length up to 20 inches. It has gray- nesting. brown plumage with white spots on the back; whitish or grayish underparts are barred with buff or deep brown, Snowy Owl the barring crosswise on the breast and lengthwise on the Rare and irregular visitors to the Keystone State, snowy belly. owls show up mainly from November to January. If food The barred is the most vocal of our owls. Its hoots are
94 Screech Owl more emphatic than those of the great horned owl's, but The screech owl is the only small Pennsylvania owl with not as deep or booming. The barred owl's call is eight ac- ear tufts. It is 10 inches long, with a 22-inch wingspan cented hoots, in two groups of four hoots: hoohoo-hoohoo and a 6-7 ounce body weight. The species is dichromatic, . . . hoo-hoo-hoohooaw (described as "Who cooks for i.e. exhibiting two color phases — gray and red — inde- you, who cooks for you all?"). It usually calls early in the pendent of age or sex, consistent from first plumage to night, at dawn, and occasionally on cloudy days. old age and frequently found in a single brood. Gray phase Barred owls almost always nest in hollow trees, laying 2-4 birds are a dappled brownish-gray; red phase individuals eggs that hatch in 28-33 days. Pairs may show strong attach- are chestnut-red, also dappled. The pale breast and belly ment to the same nest area, returning year after year. are streaked with dark gray or chestnut, depending on the color phase. In Pennsylvania, the gray phase is prob- Long-Eared Owl ably ten times more common than the red phase. The long-eared is one of the most efficient mouse- A screech owl's call is termed a "quavering whistle," catchers of the Pennsylvania owls. This slender, crow-size "mournful wail" or "long, descending whinny with tremolo, owl has long wings which make it appear larger in flight repeated at irregular intervals" ( huhuhuhuhu , etc.). than it actually is; a long-eared has a 16-inch body length, Screech owls nest in unlined cavities of hollow trees, a 40-inch wingspan and weighs about 11 ounces. This in abandoned holes of flickers and pileated woodpeckers uncommon Pennsylvania resident gets its name from two and even in birdhouses. In March, the female lays 4-5 eggs; prominent ear tufts. incubation takes 26 days. After hatching, young remain While it looks a bit like a small version of the great in the nest for one month. horned owl, the long-eared can be told from its larger rela- Large insects such as grasshoppers, moths and beetles, tive by a streaked belly — rather than barred — and mice, shrews, small birds, crayfish, frogs and flying squir- closer-set ears. Like the great horned, the long-eared has rels form the screech owl's diet; most non-insect food is a rusty face and grayish-brown plumage. The long-eared taken during winter. Screech owls hunt by flying low and hoo, hoo, hoo owl's call is a low, moaning, dove-like re- swiftly over fields. Common in our state, they live in farm peated every three seconds or so. woodlots, orchards, stream edges and wooded areas of Long-eared owls usually nest in dense conifers, fre- towns and cities. quently in old crow or hawk nests. Females lay 3-8 eggs (normally 4-5). Only the female incubates; incubation Saw-Whet Owl period is around 25 days, and the oldest owlet may be 8- With a body length of eight inches and an 18-inch wing- 10 days old when the last egg hatches. span, the saw-whet is the smallest Pennsylvania owl. Its Long-eared owls feed mainly on mice and shrews, oc- plumage is dull chocolate-brown above, spotted with casionally taking birds, insects and frogs. They are prob- white, and its undersides are white spotted with dark red- ably the most nocturnal of our state's owls. Prime habitat dish-brown. Juveniles are a rich chocolate-brown over is dense or open coniferous and deciduous forests. most of their bodies. This species has no ear tufts. The saw-whet's call is a mellow, whistled note repeated Short-Eared Owl mechanically, often between 100 and 130 times a minute: Also called the marsh owl, the short-eared visits Penn- , etc. This sound suggests the rasping too, too, too, too, too sylvania mainly in winter. It is a crow-size owl (body length made when sharpening a saw — hence the bird's name. 13-17 inches, weight 15 ounces) with long wings (up to a The saw-whet is nocturnal and seldom seen. By day, it 42-inch wingspan). roosts in young, dense hemlocks or thickets. Its upper plumage is streaked and buff-brown, with Saw-whet owls breed from March to April; they nest large buffy areas on the upper wing surfaces; the breast is in deserted woodpecker and squirrel holes, hollow trees pale, boldly streaked with brown. The short-eared owl's or stumps and nesting boxes. Females lay 4-6 eggs that ear tufts are small and hard to see, but its ear openings hatch after 21-28 days. Immatures leave the nest when are large and its hearing excellent. about a month old. Saw-whets feed on insects, mice, frogs, The short-eared is fairly diurnal (active in the day). It bats, voles, shrews and small birds. In turn, they are preyed hunts over open country, and its irregular, flopping flight upon by barred and great horned owls. resembles that of a nighthawk or large moth. The short- eared is a fairly silent owl but occasionally sounds an or a hooting call de- keaw, keaw, emphatic, sneezy bark, boo, boo, boo . scribed as At winter's end, most short-eared owls leave Pennsyl- vania and head north. Some remain in our state to breed, nesting in slight depressions in the earth or sand sparsely lined with grasses, weed stalks and feathers. Bushes or Wildlife Notes are available from the clumps of weeds often hide the nest. The female lays 4-7 Pennsylvania Game Commission eggs and incubates them about 21 days until they hatch. Bureau of Information and Education Mice form over 75 percent of this owl's diet, but it also Dept. MS, 2001 Elmerton Avenue preys on shrews, rats and small birds. The short-eared de- Harrisburg, PA 17110-9797 pends mainly on its sense of hearing to locate mice. This www.pgc.state.pa.us owl avoids woodland; it is found in open country, fresh or saltwater marshes and boggy land. An Equal Opportunity Employer
95 Wildlife Note — 19 LDR0603 Ring-Necked Pheasant by Chuck Fergus When man imports creatures to lands where they don't ish rump and lower back. Tail feathers of both sexes are naturally exist, he often brews trouble. Consider the im- brown with black bars. pact and spread of the rabbit in Australia, the red deer The crowing of a rooster is distinctive: A loud double in New Zealand, and the English sparrow and starling in squawk followed by rapid muffled wingbeats which may the United States. The ring-necked pheasant is an im- or may not be audible, depending on distance. Males port, too, but unlike the species mentioned above, it crow most often during mating season, especially at sun- hasn't become a pest. In fact, this Asian native has proven rise and sunset; they may also emit a loud cackle when to be a fine member of North America's wildlife commu- flushed into flight. Hens are normally silent. nity. The ringneck is the hunter's bird — imported, Pheasants eat weed seeds (ragweed, smartweed, fox- stocked and transferred to suitable habitat throughout tails, etc.), grains (corn, wheat, barley, oats, beans and the nation by wildlife departments. Today, the ringneck buckwheat), fruits and berries (raspberries, dewberries, benefits us all, providing enjoyment to hunters, strawberries, thornapples and barberry), shoots, leaves, birdwatchers and nature lovers of all types. grasses, rose hips and insects. They find a lot of their food The species is found throughout the United States, by scratching through ground litter. except in the southeast, parts of the southwest, and the Like most birds, ring- far north. Good populations exist in farming regions of necks have sharp Phasianus the Midwest. The ringneck's scientific name is senses of hearing colchicus , and it is a member of the Phasianidae, or pheas- and sight. Ex- ant, family. Closely related to quails and grouse, the ring- tremely wary neck belongs to the order Galliformes, which also in- in autumn, cludes turkeys, ptarmigan and prairie chickens. Biology An adult male weighs 2½- to 3½ pounds, an adult fe- male, two pounds. Males are called roosters, cocks or cockbirds; females are hens. The standing height of a rooster is about one foot, and its length, from beak to tail tip, averages 36 inches. Hens are slightly smaller. A pheasant is long-legged and rangy through the body, with a long, pointed tail (20 to 23 inches) and short, rounded wings. A hen's plumage is a subtle, camouflaging mixture of brown, black and gray. In contrast, a rooster's feathers are a beautiful mix of reds, browns, golds and black. A rooster has scarlet cheek patches, a white neck ring usu- ally interrupted in the front, an iridescent greenish-black head, golden-brown breast, and a greenish-gray or blu-
96 until young are able to roost in trees. Instinctively, chicks they stick to dense cover when hunted heavily. During squat and remain motionless at a signal given by the hen; spring and summer they can be seen strutting across their coloration, tan with darker brown streaking, con- freshly mowed fields and along roadsides. When pursued, ceals them well. Foxes, raccoons, crows, weasels, house pheasants would rather run than fly, dodging nimbly into cats, dogs and hawks prey on the young. heavy cover — brambles, honeysuckle or multiflora rose. The hen guides her chicks in finding food; insects, When cornered or surprised, they take to the air. Strong plentiful and high in protein, are a good early food. By fliers over short distances, they attain a maximum speed two weeks of age, chicks can fly short distances; after six of 45 miles per hour in the open. Outside of breeding weeks, their adult plumage starts to come in; and by au- season (when roosters stake out individual territories) tumn, birds of the year look like adults. Young roosters and brood-raising periods, pheasants are relatively gre- can be told from older males by the length and hardness garious, roosting in groups. In Pennsylvania, pheasants of their spurs — appendages growing out from the backs often roost in trees. The average pheasant ranges within of their legs. In young birds, the spurs are relatively soft, one square mile. blunt, and short (a quarter-inch or less). Older roosters Roosters claim individual breeding territories each have hard, sharp spurs up to an inch in length from spur spring. A rooster's courtship display includes spreading tip to the front of the leg. his tail and wings and strutting; his red cheek patches In winter, pheasants may form flocks. During inclem- are swollen, his head is held low, and his neck feathers ent weather, they stick to the thick protective cover of are ruffled. With luck and persistence, he will collect a conifers, brushy sloughs or forests overgrown with veg- harem of hens. Breeding begins in late March or early etation. While not commonly occurring, the following April and may extend into August. The male does not diseases afflict pheasants: coccidiosis, blackhead and help incubate eggs or raise young. pullorum. Flukes, tapeworms and roundworms parasitize Nesting occurs from April to August. A hen selects a some individuals. There is an annual removal rate, from nest site on the ground in a hayfield, a weedy field, an all causes, of 90 to 95 percent for roosters and more than overgrown pasture or a brushy fencerow. A natural hol- 60 percent for hens. low (or one scraped out by the hen) is lined with weeds, grasses and leaves. Surrounding vegetation helps con- Population ceal both the nest and the laying or brooding bird. The female lays 6 to 15 eggs (average is 10 to 12) The first successful pheasant introduction to North over a 2-week period. Eggs measure about 1¼ by 1¾ America was a release of about 30 birds in Oregon's inches and are light tan to pale olive green in color. In- Willamette Valley in 1881. Many of America's ringnecks cubation usually doesn't begin until the last egg is laid, have descended from those 30, hybridizing with other so all eggs receive equal incubation time and hatch on imported strains. The Pennsylvania Game Commission the same day. If eggs are destroyed by farm operations, began stocking pheasants in 1915. predators, fires or floods, hens may renest, some even Since Pennsylvania's ring-necked pheasant population making up to three attempts. peaked in the early 1970s, the annual pheasant harvest The eggs hatch after 23 or 24 days of incubation. Most has declined from 1.3 million to about 250,000 birds. clutches hatch by early July. Like the young of other galli- During its heyday, wild pheasants numbered in the mil- naceous species, pheasant chicks are precocial — cov- lions and accounted for a majority of the harvest. As the ered with down, their eyes open, able to run about and '70s progressed, however, the pheasant population de- eat as soon as their down dries. Chicks depend on the clined, and today pheasant hunting is largely sustained hen to shelter them from cold and rain (she does this by by stocked birds. brooding, or sitting on top of them). Hens brood at night Wildlife managers have long contended that habitat loss and land-use changes have caused the ringneck's plunge. In recent years, thousands of farmland acres have been lost to industrial com- plexes, shopping malls, suburban de- velopments and urban sprawl. On ar- eas still being farmed, smaller fields have been consolidated into bigger ones to accommodate larger farm equipment, causing a loss of fencerows and other areas where pheasants once found food and shelter. Changing farm- ing practices also include an increased use of pesticides and herbicides, which kill the insects and weedy cover vital to pheasants. Nowadays hay is mowed earlier and more frequently, giving hens little or no time to raise a brood. Fencerows and wind-
97 breaks have vanished. Even harvested cornfields, always a popular hangout for pheasants, are chopped into silage, leaving little cover for wild- life. In the '70s, pheasant chicks, for the first few weeks of life, could find all the food and cover they required without leaving the hay field they were hatched in. Now, if a hen is able to even hatch her brood before the hay is cut, she and her young must range farther to ob- tain adequate food and cover, greatly in- creasing their exposure to predators, cars and other dangers. Habitat Prime pheasant habitat is farmland that has occasional weed fields; blackberry, sumac and honeysuckle patches; swamp edges and marshy depressions grown up in cattails, grass and sedge; and overgrown drainage ditches. Clean-farming practices, where every bit of ground is put into production, reduce the diversity of food and cover pheasants need. Winter food and cover are important to pheasant popu- lations. Good foods are thornapples, apples, rose hips, good summer, fall and winter cover, and the beans are skunk cabbage, ragweed, burdock, grapes, grasses, green eaten from fall to spring. Forest edges can be cut to in- vegetation and Japanese barberry; these, along with grain crease low, brushy growth, which makes good cover. Au- (especially waste corn left by mechanical harvesters) help tumn olive, honeysuckle and pine plantings also improve birds overwinter. Pheasants locate food in areas melted cover. However, these things alone will not increase the or blown free of snow, or by scratching. Pines provide ex- pheasant population. Safe nesting cover will. This is the cellent cover for roosting and daytime resting. Pheasants most important factor when bird numbers fluctuate widely also seek out densely vegetated marsh or creek-side ar- from year to year. To reduce nesting losses, farmers should eas during bitter weather. delay their first alfalfa cutting until the end of June. Farmers can manage their land to produce more pheas- Given adequate food and protective cover, ringnecks ants. Strips of corn may be left unharvested (5 to 10 rows can pull through rough winters. They are hardy birds and, next to cover are adequate); unpicked soybeans make like all wildlife, have keen survival instincts. Wildlife Notes are available from the Pennsylvania Game Commission Bureau of Information and Education Dept. MS, 2001 Elmerton Avenue Harrisburg, PA 17110-9797 www.pgc.state.pa.us An Equal Opportunity Employer
99 Wildlife Note — 24 LDR0603 Porcupine by Chuck Fergus The porcupine is a blackish, quill-armored, slow-mov- The most distinctive aspect of a porcupine's appear- ing rodent with an appetite for tree bark and salt. It lives ance is its coat of quills. Quills cover the animal's upper in forests and often can be seen hunched into what ap- parts and sides from the crown of its head to the tip of its pears to be a black ball high in a tree. While it doesn't tail. They're 1 to 4 inches long (those on the animal's occur in all parts of Pennsylvania, the porcupine is one back are longest), yellow or white tipped with black, and of our best-known and most easily identified wild ani- lined with a foam-like material composed of many tiny mals. air cells. An individual porky may have up to 30,000 . The word Its taxonomic name is Erethizon dorsatum quills. porcus "porcupine" comes from two Latin words, When a porcupine is relaxed, the quills lie smoothly spina ("thorn"), which also reflect the spe- ("swine") and along its body, but when it feels threatened, muscle con- cies' colloquial name, quill pig. In the East, porcupines tractions cause the shafts to rise. In reality, quills are spe- inhabit Canada and New England south into Pennsylva- cialized hairs. The rest of the pelt consists of long, stiff nia; they range through the northern Midwest and the guard hairs and soft, wooly underfur. Two molts occur Pacific Northwest, south in the forested Rocky Moun- each year: in spring, short hairs replace winter underfur; tains nearly to Mexico, and north to Alaska. They live and in fall, the long, insulating underfur grows back in. at all elevations from sea level to timberline. At all times, quills are present and are replaced as they fall out. Biology To defend itself, a porcupine turns its back to a po- tential enemy, tucks its head between its front legs (or Adult porcupines are about 30 inches in length, in- under a convenient shrub), and flails its quill-studded cluding a 6- to 10-inch tail. They weigh 9 to 15 pounds, tail back and forth. It may back toward an adversary, with bigger, older adults weighing up to 20. Males are chattering its teeth. larger than females. The porcupine is North America's second largest rodent; only the beaver is bigger. A porky has four incisors, two above and two below; they are bright orange, strong and adapted to gnawing. Short-legged and stout of body, a porcupine has a pronounced arch to its back. Its skull is heavily constructed; the small, rounded head has a blunt muzzle, ears almost hidden in fur, and dull black eyes. The front and back feet bear long, curved claws, and the soles of the hind limbs are thick-skinned and cal- lused. The tail is short and club-shaped. Porcupines vary in color from salty- black to brownish-black, sprinkled on the sides and belly with yellow- or white- tipped hairs. The summer sun bleaches the guard hairs of some porkies, giving them a grizzled appearance. Albinism sometimes occurs.
100 trunk, the bark will, in time, close over the wound. If a Porcupines cannot throw their quills, but because the porcupine girdles the trunk, however, the tree will die. quills are loosely attached, they dislodge easily on con- Trees with upper branches freshly "barked" (the newly tact and stick in a victim's flesh. A single quill has a exposed wood shows light against the bark) show that a needle-shaped tip covered with hundreds of minute, porcupine's in the area. Beech trees are often damaged overlapping, diamond-shaped scales. The scales slant only at their bases, perhaps because porkies have a hard backward and act as barbs. When a quill lodges in tissue, time climbing this smooth-barked species. actions of the victim's muscle fibers engage the tips of Although porcupines kill a few trees by girdling, most the scales, drawing the quill or quill fragment inward up authorities agree the damage they cause over large areas to an inch a day. A wild animal badly impaled in the body is generally insignificant. will suffer intensely; quills may pierce its heart, arteries, Porcupines grunt, groan, shriek, bark or lungs and cause death, or they may sever and whine; their calls may carry up to a the optic nerves and cause blindness. quarter-mile. In breeding season, por- Slow and clumsy on the ground, por- kies are especially vocal. cupines are more at home in trees. A Breeding takes place in Septem- porky scales a tree by digging in ber, October and into November, with its sharp claws, pressing the after a courtship often lasting rough, leathery soles of its feet several days. Courting porkies against the bark, and bracing rub noses, chatter their teeth, with its sturdy tail. It descends walk on their hind feet or per- tail first. form stylized, weaving body On the ground, a porcupine movements. Males are polyga- can muster a top speed of about mous and play no part in rear- 2 mph over short distances. It ing young. In females, estrus waddles along in plantigrade fash- (the period when they're sexu- ion, on the soles of its feet with ally receptive) repeats every its heels touching the ground. 30 days until mating occurs or Sensitive facial whiskers help it the breeding season ends. maneuver through thick under- Unlike most rodents, porcu- brush. pines are not prolific reproduc- A porky can see moving ob- ers. Wildlife biologists have es- jects only at short range and is timated that up to half of all almost blind to stationary ob- adult females go unmated each jects. Its hearing is probably in- year, and females that do become ferior to that of most other impregnated almost always pro- mammals, but it has a keen duce just one offspring. The sur- sense of smell. A porcupine can vival rate of young porcupines is swim, its air-filled quills helping high. After a gestation period of 205 to keep it afloat. to 217 days, the female gives birth in Porcupines are vegetarian. In April, May or June. Birth may occur in a winter, much of their diet consists of ground den, although the female doesn't needles, twigs and small limbs of ever- generally select a particular site. greens, especially hemlocks. They also eat the inner bark The young porcupine is called a "pup" or of trees: hemlock, spruce, white and pitch pine, basswood, "porcupette." As might be expected after such a long sugar and striped maple, beech, birch, aspen, ash, cherry, gestation, it is precocial — it weighs about a pound, its apple and other species. In spring, summer and fall, por- eyes are open and it's about 10 inches long and fully kies eat a wide variety of vegetation, including grasses, furred. The quills are soft and hairlike, about a quarter- sedges, and the flowers, leaves, twigs, roots, buds, cat- inch long, but they become hard and functional as they kins and seeds of many other plants. dry. Pups are able to climb trees and eat solid food within As a porcupine strips a tree of bark or foliage, small a few days. They nurse for about 50 days. branches frequently fall to the ground; these trimmings After weaning, pups receive little attention from their play a minor role in providing food for other animals mothers; females and young separate for good after about during winter. six months. Young are sexually mature at 15 to 16 months In wild areas, porcupines gnaw on shed deer antlers. and breed in their second autumn. Closer to civilization, their chewing damages wooden Porcupines den in caves, rock crevices, hollow logs buildings, telephone poles and ornamental trees. and trees, deserted fox dens, brushpiles and abandoned Porcupines crave salt. They're attracted to and will buildings. They have a habit of defecating at their den's gnaw on objects that have been in contact with human entrance, and the resulting pile of droppings is a good perspiration — axe handles, ropes, work gloves, leather indicator of the animal's presence. boots, etc. They're occasionally seen along highways In winter, porcupines take to their dens for protec- where salt has been used to melt ice. They're also said to tion from snow, wind and predators. Several porkies may relish the glue in plywood. use the same den site, together or at different times. An If a porcupine chews off an isolated section on a tree's
101 individual generally becomes resident at a den in Novem- Pennsylvania; the timbered land in the northwest and ber and uses it off and on until May. During winter, a porky northeast corners; and the wooded sections of the may spend its days asleep in the den or in the top of ridge-and-valley region. Few, if any, porkies live in the southwestern or southeastern parts a conifer in which it's been feeding. Porcupines of the state. do not hibernate. Mammalogists have theorized that the por- Winter dens are rarely used in summer; dur- cupine originated in South America, crossed the ing the warm months, a porcupine may choose Isthmus of Panama during the Pleistocene pe- a large deciduous tree — often an oak — as a riod, and overspread North America. Today, daytime rest site. Porcupines are solitary in summer. Throughout the year they do most three other genera of New World porcupines in- habit South America. of their feeding and moving about at dusk, during the night, and at dawn. Porcupines seem to be holding their own. The In Pennsylvania, porcupines are species thrives in a variety of forest, terrain and climate types across the continent — and it has preyed upon by foxes, coyotes, bobcats, few enemies in the wild. dogs and owls. The fisher, reintroduced in Pennsylvania in the mid-1990s, has mastered the technique of flipping a Habitat porcupine onto its back, exposing the rodent's unquilled, vulnerable belly, Porcupines live in forests but can be found away and killing it with a swift bite. Fishers from tall trees if brush is available. They do well in also kill porcupines with repeated bites mixed hardwood — conifer woodlands with suitable to the face and head. Also, coyotes den sites — rock crevices, caves, hollow trees, etc. — have been known to work in pairs to ma- and they live in wooded valleys as well as on the neuver a porcupine onto its back. mountaintops. Porcupines have a 10- to 12-year life The winter range of a porcupine includes its den, expectancy in the wild. Mortality factors include coniferous feeding areas (primarily hemlocks), and the predation (primarily by man), accidents (many porkies travel lanes linking them — up to about 20 acres. A single are killed on the highways) and disease. Porcupines are animal may spend several months feeding on only one or parasitized by lice, ticks and mites, some are afflicted with two trees and using the land between them and its den. mange, and many have tapeworms and other internal para- Summer ranges are larger, between 15 and 65 acres, with sites. an average of 45 acres in deciduous woods. The summer ranges may be a half-mile or farther from the winter ranges, Population as den sites and conifers aren't important components of summer territories. In summer, porcupines favor decidu- In our state, most porcupines live in areas of extensive ous forests, especially areas with high concentrations of forests. They inhabit the rugged mountains of northcentral oaks. Wildlife Notes are available from the Pennsylvania Game Commission Bureau of Information and Education Dept. MS, 2001 Elmerton Avenue Harrisburg, PA 17110-9797 www.pgc.state.pa.us An Equal Opportunity Employer
102 Wildlife Notes Allegheny Woodrat Northern Cardinal, Grosbeaks, Indigo Bunting Bats and Dickcissel Beaver Opossum Black Bear Otter Blackbirds, Orioles, Cowbird and Starling Owls Blue Jay Porcupine Bobcat Puddle Ducks Bobwhite Quail Raccoon Canada Goose Rails, Moorhen and Coot Chickadees, Nuthatches, Titmouse and Brown Raptors Creeper Ring-necked Pheasant Chimney Swift, Purple Martin and Swallows Ruby-throated Hummingbird Chipmunk Ruffed Grouse Common Nighthawk and Whip-Poor-Will Shrews Cottontail Rabbit Snowshoe Hare Coyote Sparrows and Towhee Crows and Ravens Squirrels Diving Ducks Striped Skunk Doves Tanagers Eagles and Ospreys Thrushes Elk Vireos Finches and House Sparrow Vultures Fisher Weasels Flycatchers White-tailed Deer Foxes (Red & Gray) Wild Turkey Gray Catbird, Northern Mockingbird and Woodchuck Brown Thrasher Woodcock Herons Wood Duck Kingfisher Woodpecker Mallard Wood Warblers Mice and Voles Wrens Minks & Muskrats
103 Wildlife Note — 36 LDR0603 Puddle Ducks by Chuck Fergus Puddle ducks — also called dabbling ducks — are the of each wing. Speculum color varies from species to spe- largest and most widespread group of waterfowl in the cies and may function as a flashing signal to help keep a world; they include the wild ducks most familiar to flock together. To the human observer, the speculum is people. This Wildlife Note covers seven species com- often a telltale field mark. monly found in Pennsylvania (American black duck, Within the species, males (called drakes) have bright, gadwall, northern pintail, green- and blue-winged teal, colorful plumage, while the females (hens) are drab. In wigeon, and northern shoveler); the mallard and wood fall, winter and spring, drakes are feathered in their nor- duck are also puddle ducks, but they are featured indi- mal bright coloration; in early summer, after breeding vidually in other Notes. season, they molt into a drab "eclipse" plumage and re- The two major duck groups, puddle and diving ducks, semble the hens for several months. differ in several ways. Divers inhabit large deep lakes and North American puddle ducks breed across the north- rivers, and coastal bays and inlets; puddle ducks tend to ern part of the continent; some species — mallards, black stick to the shallows of lakes, rivers and freshwater and wood ducks — nest in Pennsylvania. They generally marshes, although they frequent saltwater, especially dur- mate for the first time when a year old. During courtship, ing migration. Diving ducks are, as their name implies, drakes chase the hens and engage in fighting, ritualized adept at diving and obtain most of their food this way. movements, posturing and calling. After mating, the Puddle ducks prefer to feed on the surface or close to it; drake leaves immediately, or he stays with the hen while often they stretch their heads underwater, feeding up- she is laying and then departs soon afterward. Pair bonds ended with their tails in the air. As a group, they are not are weak, and a different mate will be courted each year. accomplished divers, but adults dive occasionally and The hen lays a large clutch of eggs (7 to 13, depending ducklings do so frequently. on the species) in a nest built of grasses, leaves and reeds, Puddle ducks feed in the water along the fringes of hidden among vegetation. She incubates and cares for islands and shorelines and on dry land. Their diet con- the brood by herself. sists mainly of vegetable matter — seeds, grasses, leaves Ducklings are covered with down; they are a pale and stems of underwater plants, agricultural crops and brownish color, streaked with darker lines to disguise nuts — along with mollusks, insects and fish. their body outlines. Minutes after hatching, they can swim These shallow-water ducks ride higher in the water and feed themselves. They first fly at about two months than their diving cousins, and launch themselves directly of age. upward when taking off; they do In autumn puddle ducks fly south, along with diving not need to run across the wa- ducks and geese. Waterfowl start migrating through ter to build up speed for take- Pennsylvania in late August; the movement peaks in off like diving ducks do. October and ends in December. Some puddle ducks oc- Puddle ducks are excellent casionally winter in Pennsylvania, but most spend the swimmers, sure-footed on cold months across the southern United States and in land, and swift agile fli- Central America. ers. On the wing, they Raccoons, foxes, minks, hawks and owls prey upon often display a specu- ducks. Raccoons, skunks and crows eat the eggs; snap- lum, or wing patch ping turtles and fish take the young. — a bright, iri- Taxonomists group puddle ducks in family Anatidae, descent panel of subfamily Anatinae. The Anatinae form the largest and feathering close most diverse of the commonly recognized waterfowl sub- to the body on families, with more than 40 species worldwide. Pennsyl- the trailing edge vania puddle ducks all belong to genus Anas .
104 muskgrass and pondweeds. In Black Pennsylvania, gadwalls are uncommon. They are consid- Ducks Pintails ered non-breeding residents, although they have nested in Crawford and Butler coun- ties. They breed mainly in the western United States, Canada and Alaska. Hens seek dense, dry weed cover, hiding the nest from above and all sides. They lay about Gadwalls 10 eggs, which hatch in 26 days. Gadwall are most plentiful in the Dakotas and Canada's prairie provinces, less common on the Atlantic Flyway. They are often seen with pintails and wigeons, but they rarely congregate in large flocks. The gadwall dives more often than any other puddle duck. Northern Pintail — Length, 20 to 29 inches; average American Black Duck — Length, 21 to 26 inches; weight, 1.9 to 2.3 pounds; slender and trim. Also called average weight, 2.4 to 2.8 pounds. Also called "black "sprig." Among the most beautifully marked of our ducks, mallard" or "red leg." Plumage is a dark, mottled brown a pintail male in breeding plumage has a brown head, with white underwings and a violet-blue speculum. white neck and breast, and a gray back and sides. Fe- When visibility is good, the contrast between the light- males are grayish brown. The speculum is metallic green- brown head and the brown-black body is noticeable. This ish-brown with a white rear border, but far more notice- is our only puddle duck in which the plumages of both able in flight is the male's long, slender, pointed tail. Pin- sexes are almost identical; the drake in nuptial plumage tails are extremely graceful and fast fliers, fond of zigzag- has a bright yellow bill, contrasting with the female's ging from great heights before leveling off to land. Voice: olive-green bill. The voice of the hen is a loud ; of quack . the drake has a flute-like whistle, the hen a soft quack the drake, a lower-pitched kwek-kwek. In summer and fall, pintails feed largely on seeds and Black ducks eat a variety of vegetable foods, includ- vegetative parts of pondweeds and widgeon grass, and ing eelgrass, widgeon grass, and the seeds of sedges, bul- on the seeds of bulrushes and smartweeds. Nesting fe- rushes, wild rice, pondweeds, smartweeds and millets. On males eat more aquatic insects. Sometimes pintails land land they feed on acorns and waste corn, willingly flying in harvested fields to glean waste corn. They breed up to 25 miles to a reliable source of the latter. Animal mainly across Canada, the northwestern United States foods, more important in winter, include periwinkles, and in Alaska, also in the Eastern Hemisphere; in Penn- mussels and snails. sylvania, nests have been reported in Crawford County Black ducks breed in Pennsylvania, nesting in marshes, and the John Heinz National Wildlife Refuge at Tinicum bogs, and lake and stream margins, and often in wooded near Philadelphia. Pintails often nest in dead herbaceous uplands. They nest on the ground, on stumps and dead cover of the past year's growth, which may offer little snags, and occasionally in tree cavities; eggs, 8 to 10, concealment; the site is usually within 100 yards of wa- hatch in about 4 weeks. ter, but may be up to a mile away. Females lay about 9 Once the most popular duck in the waterfowl hunter's eggs; they hatch following a fairly short incubation pe- bag, the black duck has dropped to third place, behind riod of 21 days. A few pintails winter in Pennsylvania, the mallard and wood duck. The black duck population but most fly to the southern United States and Central declined steadily in the 1960s and '70s. In 1982, harvest America. restrictions were implemented and the population ap- pears to have stabilized, but is well below its historic num- — Length, 13 to 16 inches; aver- Green-winged Teal bers. age weight, ½ to 1 pound; the smallest of our ducks, about the size of a pigeon. The male is beautifully colored with — Length, 19 to 23 inches; average weight, Gadwall a dark, reddish-brown head, a green streak over the eye, 1.8 to 2.2 pounds. Sometimes called "gray duck." Males and a vertical white stripe on the side. The female is pri- in breeding plumage have brown heads, gray bodies and marily brown. The speculum shows green in both sexes. black tails. The female is similar, but more brown in color. Green-winged teal fly swiftly, often in small, tight flocks. The legs are yellow. This is the only puddle duck with Drakes whistle and have a tittering call; hens sound a white in its speculum. The drake whistles and sounds a faint quack . ; the hen quacks like a mallard, but more rap- kack-kock Green-winged teal prefer small and shallow, but per- idly and higher pitched. manent, freshwater ponds, with thick cover nearby. They Food is basically aquatic plants. On brackish or fresh- feed on small seeds of grasses, bulrushes and smartweeds, water estuaries where they often winter, gadwalls con- and on the stems and leaves of pondweeds. They also eat centrate on vegetation such as widgeon grass, eelgrass,
105 American Blue-Winged Wigeons Teals Green- Winged Teals Shovellers tiny mollusks, snails and other crustaceans. male has a cinnamon-red neck and head, with a white stripe A few green-winged teal may be found nesting in Penn- from the forehead to the middle of the crown and an iri- sylvania, although the duck's primary breeding range is descent green patch coming back from the eye; the body farther north, across Canada, the northwestern United is pinkish-brown, the speculum blackish with a hint of States, and Alaska. Courting birds engage in much whis- green. The female's coloration is similar, but duller. The tling and posturing. Females hide their nests in dense species can best be identified in flight by the white belly patches of shrubs and weeds, or in tall grass at the edge of and fore-wings. Wigeons are wary birds, quickly reacting a lake or slough. They lay 8 to 10 eggs and incubate them to potential threats and disturbances; they fly swiftly in compact flocks, wheeling and turning in unison. Males 21 to 23 days; they vigorously defend their nest. Some green-winged teal occasionally winter in Pennsylvania, have a 3-syllable whistle with the middle note the loud- but most go farther south. est; hens utter a loud koow and a lower qua-awk . Wigeons feed on aquatic plants, sometimes coming Blue-winged Teal — Length, 14 to 16 inches; average ashore for shoots of grains and grasses. They breed in the weight, ¾ to 1 pound. The drake has a brown body and a northwestern United States, Canada and Alaska, nesting slate-gray head; in front of the eyes is a distinctive white in dry, sedge-lined meadows around lakes and sloughs. crescent. The hen is primarily brown. Both sexes have a The 7 to 9 eggs are incubated about 23 days. Wigeons blue patch on the fore-wing and a green speculum, but migrate through Pennsylvania in September and Octo- patches are more prominent on the males. Blue-winged ber. Some occasionally winter here, but most go to the teal are shy, common waterfowl, found on ponds, marshes southern states and farther south. and protected bays, often with other puddle ducks. Their small, compact flocks fly swiftly, often low over the marsh, Northern Shoveler — Length, 17 to 22 inches; weight, twisting and dodging around trees and bushes; the birds about 1½ pounds; size similar to the mallard, for which it sound a twittering flight call. Additional calls: drakes have is often mistaken. Also called "spoonbill" for its long, , and hens a soft tseet tseet tseet a whistling quack broad bill. The male has a green head, white breast and . Blue- wings are our earliest migrants; they head south in late chestnut sides. The female is a mottled brown. The best August and September. field marks are the outsize bill, held downward as the bird Food includes seeds and vegetation of aquatic plants, rides in the water; and, in flight, blue upper-wing and white especially pondweeds, widgeon grass, duckweed and mil- under-wing coloration. Females have a typical quacking took-took call, males a let. They often feed near green-winged teal, the blue-wings . Shovelers usually travel in small consuming more animal matter. flocks of 5 to 10 birds. Food: invertebrates (caddis fly larvae, dragonfly Blue-winged teal occasionally nest in Pennsylvania, in nymphs, beetles, bugs), duckweeds and seeds of pond- borders of freshwater sloughs, swamps, ponds, and marshes. weeds and bulrushes. In deep water, shovelers apparently They lay 10 to 13 eggs in a basket-like nest built on dry ground. Surrounding vegetation usually arches over the feed on surface plankton, taking in a steady stream of water at the tip of the bill and expelling it at the base, nest, concealing it. Incubation is 23 to 24 days. straining out microscopic plants. The blue-winged teal is a familiar, common duck of Shovelers breed in the northwestern United States, inland North America, although its numbers have been Canada and Alaska. Females nest in grassy cover, some- reduced through cultivation and habitat destruction in times well away from water. The 10 eggs hatch in 3 to 4 its primary breeding range, the prairie pothole region in mid North America. weeks. Shovelers pass through Pennsylvania in March and April, and again in September and October. They winter along the southern United States coast and in western — Length, 18 to 23 inches; aver- American Wigeon states and Central America. age weight, 1½ to 2 pounds. Also called "baldpate." The
106 Wildlife Notes Allegheny Woodrat Opossum Bats Otter Beaver Owls Black Bear Porcupine Blackbirds, Orioles, Cowbird and Starling Puddle Ducks Blue Jay Raccoon Bobcat Rails, Moorhen and Coot Bobwhite Quail Raptors Canada Goose Ring-necked Pheasant Chickadees, Nuthatches, Titmouse and Brown Ruby-throated Hummingbird Creeper Ruffed Grouse Chimney Swift, Purple Martin and Swallows Shrews Chipmunk Snowshoe Hare Common Nighthawk and Whip-Poor-Will Sparrows and Towhee Cottontail Rabbit Squirrels Coyote Striped Skunk Crows and Ravens Tanagers Diving Ducks Thrushes Doves Vireos Eagles and Ospreys Vultures Elk Weasels Finches and House Sparrow White-tailed Deer Fisher Wild Turkey Flycatchers Woodchuck Foxes (Red & Gray) Woodcock Gray Catbird, Northern Mockingbird and Wood Duck Brown Thrasher Woodpecker Herons Wood Warblers Kingfisher Wrens Mallard Mice and Voles Wildlife Notes are available from the Minks & Muskrats Pennsylvania Game Commission Bureau of Information and Education Northern Cardinal, Grosbeaks, Indigo Bunting Dept. MS, 2001 Elmerton Avenue and Dickcissel Harrisburg, PA 17110-9797 www.pgc.state.pa.us An Equal Opportunity Employer
107 Wildlife Note — 9 LDR0103 Raccoon by Chuck Fergus The raccoon is a medium-size woods mammal with the fur on a raccoon's feet is light gray, and the soles of the Procyon lotor . Procyon means "before scientific name paws are hairless. Raccoons shed in April, producing dog," implying the raccoon is less advanced than the dog coats with thinner, lighter guard hairs; in autumn, heavier lotor refers to the spe- from an evolutionary standpoint; fur fills in. Usually by late November the winter coat has cies' habit of dunking food in water before consumption. replaced the shorter summer fur. At that time the pelt The common names "raccoon" and "coon" are anglicized becomes prime. versions of the Indian word "arocoun." It's fitting that Raccoons are found throughout Pennsylvania, often the common names evolved from a Native American near water — lakes, streams, rivers — but also on ridges word, as the raccoon is strictly a New World animal, found and in suburban areas. They adapt well to people and in North and Central America. human activities; some raccoons live in cities, where they As with many wildlife species, we view the raccoon den in storm drains and attics and raid garbage cans and with mixed emotions. Some raccoons are destructive, pet dishes. damaging crops and gardens, and raiding nests of domes- Raccoons are omnivorous. This means they eat both tic birds. They're valuable in many ways, too: a prime vegetable and animal matter, including wild cherries and pelt brings good money on the fur market, and hunting grapes, raspberries, blackberries, persimmons, apples, raccoons with hounds is an exciting, sport with a tradi- beechnuts, acorns, melons, corn, grass, leaves, earth- tion as old as the hills. But in the end, the true value of worms, crickets, grasshoppers, beetles, grubs, fish, frogs, any life form cannot be measured in man's terms. Rac- crayfish, mice, carrion, eggs, etc. coons have worth simply because they are one of the Raccoons have excellent senses of hearing, sight and many fascinating and interlocking segments of nature. smell. They also possess an acute sense of touch in their forefeet, enabling them to catch fish and other small, Biology quick prey. Long, sharp claws anchor slippery food items. No one knows exactly why raccoons occasionally dunk Raccoons range in size from 28 to 38 inches, which food taken in or near water before eating it. Many natu- includes a 10-inch tail, and weigh 10 to 30 pounds. Males ralists believe raccoons derive some information from are generally larger and heavier than females. Records handling the food underwater, which may cause them to exist of raccoons weighing up to 40 pounds, but indi- accept or reject it. viduals this heavy are extremely rare in the wild. Raccoons are adept climbers and, being nocturnal, A raccoon's fur is long, soft and colored a grizzled they spend most of their daylight hours in trees. On warm, black-brown. The bushy tail is marked with alternating bright days they like to sun themselves while lying flat rings of light and dark fur. Broad cheeks, a long slender on horizontal limbs, in squirrel leaf nests or curled up in muzzle, erect, rounded ears and a black strip or mask the crotches of trees. Then at night, they descend in across the cheeks and eyes give search of food. They travel, feed and hunt almost exclu- the raccoon a masked bandit- sively on the ground. Most raccoons have central home like appearance. Albinism (a dens as well as others scattered about their feeding lack of pigment produc- ranges. Adult home ranges are about a mile in diameter, ing a white individual greater when food is scarce. An ideal den or nesting site with pink eyes) and is a hollow in a large tree trunk or limb, but raccoons melanism also use old woodchuck burrows, caves, rock crevices (which pro- and abandoned farm buildings. duces a to- Raccoons have short, stout builds. Like bears, they tally black are plantigrade (flat-footed), walking on the sole of the animal) oc- foot with the heel touching the ground. They're relatively cur infre- slow runners but fierce fighters — especially females with quently. The young. Men and dogs are the adults' main enemies, al-
108 weather, food scarcities, though owls, foxes and bobcats may take young that stray development of rural from their mothers' protection. Raccoons are strong land, hunting and trap- swimmers. ping pressures, out- A raccoon makes a variety of sounds, including barks, breaks of rabies and dis- hisses, a wailing tremolo, a noise often given churr-churr temper, and habitat while the animal is feeding, and a piercing scream of alarm changes. Population or fear. concentrations vary By late autumn, raccoons have eaten enough to pro- with habitat; research- duce a heavy layer of fat that helps sustain them until ers have estimated spring, although they eat whatever food they can find in one raccoon per 0.63 winter. They do not store food. Unlike woodchucks, rac- acres of excellent coons are not true hibernators; they den up and sleep habitat and one soundly when temperatures fall below about 25 degrees, raccoon per two but emerge at different times throughout the winter dur- acres of good habi- ing warm spells. They are considerably leaner by spring, tat. having burned up much fat. Raccoons become more susceptible to disease if they Breeding takes place in January or February. Follow- overpopulate an area, because they'll encounter one an- ing a 2-month gestation period, young are born in March other more often. However, as long as fur prices provide and April. Usual litter size is 3 to 5 young, with 4 the an impetus for trappers to harvest raccoons, disease will average. Cubs weigh about three ounces at birth, are only minimally impact populations. covered with yellow-gray fur and have faintly banded tails. After about 19 days their eyes open, and when four Habitat weeks old they begin to accompany the female on short feeding forays. Weaning starts at about eight weeks; by Raccoons are adaptable, and many types of terrain the time they're three or four months old, cub raccoons provide suitable areas for them to live. As a rule, they are large and independent enough to be on their own. prefer forested areas offering plenty of den sites. They The male usually stays with the female after mating favor hardwood over coniferous forests, because hard- and until babies are born, and may help rear the young. woods provide more food (nuts, fruits) and are more apt By the time the young mature, however, the father has to develop cavities and hollow limbs suitable for shelter. usually gone off on his own. Swamps and fertile bottomlands are good habitat; rac- Many family groups — mother and offspring — stay coons often thrive near water courses, where good hunt- together through the young raccoons' first winter. Most ing opportunities exist. A raccoon will wade up a small yearling females breed at this time, but males of the same spring run in search of crayfish, aquatic insects, minnows age probably do not breed for another year. If for some and other food. reason a female doesn't breed in winter, she may become The Game Commission has never had to improve habi- receptive later in the spring and bear young in the sum- tat specifically for the raccoon because the species man- mer. Small raccoons found in the fall are the result of ages well on its own. In managing forests on state game this late breeding. By late fall, young raccoons follow their lands, however, the Commission tries to protect mature mother away from the den nightly in search of food. hardwoods, which are used as den trees by raccoons and In spring, juveniles disperse from the areas in which many other wildlife species. they were born. Young raccoons may move only a mile A varied habitat — trees of different ages and types, or two or may travel long distances. Records exist of brush, herbaceous vegetation — is ideal because it pro- young males apparently dispersing up to 150 miles, al- vides food during all seasons. In general, habitat improve- though movement of this magnitude is unusual. ment for turkeys, squirrels or deer also benefits raccoons. Raccoons exhibit some social hierarchy; most domi- Grassy openings are excellent sources for insect food. nant are older males and females with young. However, Food-producers such as grapevines, blackberry, raspberry individuals do not defend fixed territories or ranges and greenbrier patches, black cherry trees, oaks and against other raccoons. beeches should be encouraged and maintained. Beaver Captive raccoons have lived up to 18 years, but their dams benefit raccoons — and many other wildlife spe- life expectancy in the wild is probably about 10 years. cies — by producing plentiful aquatic food. Important mortality factors are lack of food in a hard, long-lasting winter, parasitism, hunting, trapping and disease. Many raccoons are also killed on highways. Population Wildlife Notes are available from the Pennsylvania Game Commission Although it experiences occasional declines, Bureau of Information and Education Pennsylvania's raccoon population is stable. Nationwide, Dept. MS, 2001 Elmerton Avenue raccoons occur in all of the lower 48 states and into Cen- Harrisburg, PA 17110-9797 tral America, but they're not found in the higher reaches www.pgc.state.pa.us of the Rocky Mountains or some of the Western deserts. Local populations may fluctuate because of severe An Equal Opportunity Employer
109 Wildlife Note — 10 LDR0603 Raptors by Chuck Fergus When the night sky brightens in the east, owls retire accidentally. to hollow trees and shady thickets. Then enter the hawks; Identifying hawks can be difficult. While males and during the day, these fascinating birds continue nature's females of the same species are generally of similar col- winnowing process — predation. ors, individual variation often occurs within the species. This wildlife note covers 11 Pennsylvania hawks: the Juveniles are especially hard to identify. Adult females northern goshawk, sharp-shinned, Cooper's, red-tailed, are generally larger than their mates — in some cases, red-shouldered, broad-winged and rough-legged hawks, nearly twice as heavy. Our hawks have yellow feet and a northern harrier, peregrine falcon, merlin and American yellow cere (area at the base of the bill). kestrel. Many hawks mate for life. They nest high above the Hawks are quick, efficient predators. They have sharp ground on sturdy limbs, in the crotches of trees or on talons and strong hooked beaks; bills and feet vary in rock ledges. Generally, nests are loosely built of sticks size and shape according to the species' prey preferences. and twigs; some are lined with down and other feathers. Eyesight of some hawks is as sharp as that of a human A mated pair will either remodel an old nest or build a looking through eight-power binoculars. The eyes of new one, occasionally starting on top of a squirrel or crow hawks are located in the front of the head; this gives the nest. The female may begin incubation before the last birds binocular vision and enables them to judge dis- egg is laid, resulting in young of different sizes in the same tance. Their hearing is acute, but their sense of smell — brood. The female does most of the incubating and is if they have one — is poor. supplied with food by the male. While hunting, hawks may soar high, sit and watch Newly hatched hawks are altricial — helpless, from a perch or strike their prey in midair. When a hawk unfeathered and covered with down, but they grow rap- drops to attack, tendons spread its feet; upon impact, idly. After about two weeks, when the young no longer the toes automatically clench and drive the talons deep. require constant brooding, the female joins the male in A snap from the hooked bill can crush a prey's skull or hunting to feed them. The young soon learn to tear meat break its back. Hawks "mantle" prey after killing, crouch- apart and feed themselves. After five or six weeks, when ing and spreading their wings to form a shield that hides flight feathers grow in, they begin taking short flights; it from other predators. several weeks later, the fledglings start to hunt. The bird may eat on Hawks help control insect, rodent and small bird popu- the ground or carry its lations. They're a natural predatory force that improves kill to a feeding a prey species by making it develop alertness, speed and spot, often a other survival attributes, and by weeding out unfit indi- fencepost or tree viduals. Hawks are also environmental indicators. If pol- limb, where it plucks lutants accumulate in natural food chains, avian preda- its prey and tears the tors are usually the first wild species to show ill effects: meat apart with its failure to reproduce, thin egg shells and nesting failure, beak. Unlike an owl, or outright death through poisoning. Heavy metals and a hawk does not swal- chlorine-based pesticides such as (the now banned) DDT, low its food whole or aldrin, dieldrin and heptachlor reduced hawks numbers. in large chunks. Many hawks fly south each autumn. The species mi- Hours after eating, a grating in greatest numbers are often those that cannot hawk will regurgitate find adequate food supplies in winter. Some hawks breed- a pellet containing ing in Pennsylvania winter as far south as Peru; during any feathers, fur or migration, a hawk can cover several hundred miles daily, Kestrel small bones swallowed depending on weather and wind conditions. In our state,
110 Red- Kestrel Shouldered Merlin Hawk Harrier Peregrine Rough-Legged Falcon Hawk many migrating birds follow ridges paralleling the Al- above smaller birds and then dive to the attack, striking legheny Plateau, climbing high on thermals that rise prey while in full flight. along these ridges. Hawk Mountain, near Kempton in southeastern Pennsylvania, is a famous spot to observe Accipiter gentilis Northern Goshawk ( ) — Length, 20 migrating hawks. to 26 inches; wingspread, 40 to 47 inches; weight, 1½ to For a long time, birds of prey were often labeled 3½ pounds. Both immatures and adults have a promi- "chicken hawks" and shot on sight. Research has shown nent white line over each eye; the eyes of adults are bright that while hawks do kill some poultry and game, in most red. Adults are blue-gray above and white below, with cases they do not drastically affect poultry operations or light barring on the breast. Immatures are brown above game populations. Today, many people get much enjoy- and creamy white below, with heavily streaked under- ment from observing hawks. In Pennsylvania, hawks are sides. The largest of our accipiters, goshawks are seen in protected by both federal and state laws. greatest numbers in winter, when food scarcities force The 11 birds of prey covered in this note fall into four many south. Also called "blue darters," goshawks are basic types: accipiters, buteos and harriers — often swift, maneuverable and relentless, sometimes pursuing lumped together under the term "hawk" — and falcons. prey — birds and small mammals — through thick un- Accipiters (goshawk, sharp-shinned hawk, Cooper's derbrush on foot. Goshawks breed in wooded areas and hawk) have small heads, long tails and short well-rounded prefer wild territory, such as the mountainous areas of wings. They fly with rapid wingbeats followed by a long northern Pennsylvania. They nest up to 75 feet above glide. Extremely maneuverable, they are well-suited to the ground in trees, building bulky nests (3 to 4 feet in the thick forest areas they inhabit. Accipiters feed largely diameter). A pair often uses the same nest year after year. on other birds. Eggs: 3 to 4, off-white and usually unmarked, incubated Buteos (red-tailed, red-shouldered, broad-winged and 36 to 38 days by the female. Goshawks defend their nests rough-legged hawks) have stocky bodies, broad rounded ca ca ca ca around the nest. fiercely; voice is a harsh wings and short fanned tails. Most are brown in color; young are similar to adults, but in most cases are streaked Sharp-Shinned Hawk ( Accipiter striatus ) — Length, lengthwise below, rather than barred. Buteos perch in 10 to 14 inches; wingspread, 20 to 27 inches; weight, 5 open country or soar in wide circles when hunting; small to 9 ounces. Identification of this species is often diffi- mammals are their main prey. cult, as large female sharpshins are nearly the size of small The marsh hawk is the only harrier found in North male Cooper's hawks, which they closely resemble. Adults America. It's long-legged, with long narrow wings and a have red eyes and are blue-gray above, with light rufous long tail. It soars with wingtips held perceptibly above barring on the breast. Immatures are brown above, the horizontal, much like a turkey vulture, quartering heavily streaked below. These are small hawks with short open country in search of prey. rounded wings and a long square-tipped tail. Sharpshins Falcons (peregrine, merlin, kestrel) have large heads, feed almost exclusively on small birds such as sparrows, broad shoulders, long pointed wings and a long tail. They warblers, vireos, etc. They fly and sail rapidly through are streamlined and built for speed, flying in a direct path the woods or hunt from a perch. Favored habitat is wood- with deep rapid wingbeats. They do not usually soar, al- land, preferably coniferous, and woods edges. Sharpshins though the kestrel sometimes hovers with rapid wing breed throughout the eastern United States, south to strokes. In hunting, the peregrine and merlin often fly Alabama. They prefer to nest in conifers, about 30 to 35
111 Broad-Winged Hawk Red-Tailed Hawk Goshawk Sharp-Shinned Hawk Cooper's Hawk feet up, usually building a new nest each year. Eggs: 4 to 5 pounds. Adults are colorful birds: dark brown above with white or bluish with brown blotches. Incubation is by both chestnut-red shoulders, rich reddish-brown and white sexes, mostly by the female, and takes 21 to 24 days. below tail strongly barred with black and white. Many Around the nest, adults make a kek kek kek sound; in flight individuals have a translucent area or "window" near the a shrill scream. wingtips, visible when they are airborne. These buteos are shy and hard to approach; they favor damp woods, ( ) — Length, 14 to Accipiter cooperii Cooper's Hawk river bottomlands and swamps. They hunt from an ex- 20 inches; wingspread, 27 to 36 inches; weight, 10 to 20 posed perch offering a wide field of view or by circling ounces (slightly smaller than a crow). Adults look like high overhead, and prey on rodents, birds, frogs and large sharp-shinned hawks — red eyes, blue-gray back and snakes. Voice is a piercing whistled which blue kee-yer, a rusty breast, except the Cooper's have rounded tails and jays often mimic. Red-shouldered hawks nest 20 to 60 the sharpshins have square-tipped tails. Named in 1828 feet above the ground in trees. Eggs: 2 to 4, usually three after William Cooper, a New York naturalist, Cooper's dull white with brown markings; incubation is by both hawks prey mainly on birds the size of robins and jays. sexes and takes about 28 days. While hunting, they prefer to perch and wait for prey. Favored habitat is woodland. Cooper's hawks breed Broad-Winged Hawk ( ) — Length, 13 Buteo platypterus throughout most of the eastern United States; they nest to 19 inches; wingspread, 32 to 39 inches; weight, 13 to in trees 20 to 60 feet up. Eggs: 4 to 5, white, incubated by 20 ounces. This small buteo is easily recognized by its both sexes but mainly by the female for about one month. heavily banded tail, with two dark and two light bands. Woods where Cooper's hawks nest may remain heavily Upper plumage is dark gray-brown; underparts are white, populated with songbirds, as these hawks hunt away from heavily streaked with brown. The broad-winged is a hawk their nest area. Call is similar to that of the sharp-shinned. of the forests, preying on snakes, amphibians, insects and small mammals. It is our most common hawk, fairly un- Red-Tailed Hawk ( Buteo jamaicensis ) — Length, 19 to wary and approachable. During migration, broadwings 25 inches; wingspread, 46 to 58 inches; weight, 2½ to 4 congregate in "kettles" of rising air, which they use to gain pounds. Upper plumage is dark brown, and the light un- height. They winter in South America. Voice is a high dersides have a belly band of dark streaking. In adults, whistled p-we-e-e-e-e. Broadwings breed mainly in decidu- the upper side of the tail is rusty red; in young, dark gray. ous forests and construct their small nests 24 to 40 feet Redtails inhabit deciduous woods. Primarily soaring birds, up in trees. Eggs: 2 to 3, dull creamy white with brown they prey on mice, birds, rabbits, red and gray squirrels, markings. Incubation (about 30 days) is mostly by the slurring down- keer-r-r-r, chipmunks. Voice is a rasping female. ward. Redtails breed throughout the East. They nest in trees 35 to 90 feet up, both sexes helping to build a stick- ) — Length, 19 to Rough-Legged Hawk ( Buteo lagopus and-twig nest lined with bark or green sprigs. Eggs: usu- 24 inches; wingspread, 50 to 56 inches; weight, two ally two, white and unmarked or with brown splotches. pounds. This species exhibits two color phases with wide Incubation is by the female, for one month. individual variation in between. Light phase: upper side light buff to white, streaked with brown; underparts white, ( Buteo lineatus ) — Length, 18 Red-Shouldered Hawk with a brown "wrist mark" partway out the wing and a to 24 inches; wingspread, 33 to 50 inches, weight 2 to 3 brown band across the abdomen. Dark phase: black or
112 prey falls to the ground, the falcon picks it up and carries sooty brown, with white at the base of the underside of it to a convenient perch to be eaten. The peregrine was the tail. Feet are feathered to the toes, hence the name near extinction and is on the federal Endangered Species "rough-legged." This large buteo often hovers over fields, List. Persistent highly toxic pesticides, which affect per- beating its broad wings in short rapid strokes much like a egrine reproduction, nearly eliminated the bird in the kingfisher or a kestrel. Its small sharp-taloned feet are eastern United States. Cornell University ornithologists adapted to kill rodents — meadow mice, voles, gophers. pioneered the restoration of this species, raising peregrines Rough-legged hawks often hunt at dusk. They nest in the from captive parents and releasing the young birds in suit- Arctic and northern Canada; like goshawks, most rough- able habitat. Recovery efforts restored the peregrine to leggeds come to Pennsylvania in the winter, when deep the East in the 1980s. They now nest on city buildings snow covers rodents on the northern feeding grounds and and bridges in Philadelphia, Pittsburgh and Harrisburg. other prey birds have migrated south. They dwell mainly Eggs: 2 to 4, creamy white covered with rich brown mark- in open country, fields and marshes. ings; 33- to 35-day incubation period. Voice is a repeated cack cack cack. or a rapid rasping we-hew Northern Harrier Circus cyaneus ( ) — Length, 18 to 24 inches; wingspread, 40 to 54 inches; weight, 12 to 16 ) — Length, 10 to 13½ Falco columbarius ( Merlin ounces. Harriers, also known as marsh hawks, have a white inches; wingspread, 24 to 26 inches; weight, 6 to 8 ounces rump patch and a ruff of feathers around the face, much (size of a blue jay). Merlins look like miniature peregrines, like the facial disks of owls. Males are pale bluish-gray with males blue-gray above and banded black above, white below; the tail, gray with on the tail. Females and young birds are dark bands. Females are brown dusky brown above, white below. The above, light brown with dark name "pigeon hawk" comes from this streaks below; tail is barred with Red-Tailed falcon's resemblance to a pigeon in black and buff. Immatures re- Hawk both flight and posture. Voice is a semble females. Marsh hawks rasping chatter. Merlins prey mainly inhabit fresh- or saltwater on birds, but also take small mam- marshes, wet meadows, bogs mals and insects. They favor open and flat open farmland. They woods or heavy timber in wild ar- prey on mice, insects, small eas. They nest about 35 to 60 feet birds and rabbits. The spe- up on ledges, in natural cavities or cies tends to congregate in in old nests of other birds. Eggs: 4 to winter. Voice is a weak nasal 5 whitish, almost covered by fine pee, pee, pee. Marsh hawks nest on brown marks. Incubation takes 30 days or near the ground, sometimes in and is by the female. fields and occasionally on a branch over the water. Nests are made of sticks, straw, grasses and are lined with feath- Falco sparverius ( American Kestrel ) — Length, 9 to ers. Eggs: 4 to 6, usually five, oval, dull white to pale blue. 12 inches; wingspread, 20 to 24 inches; weight, 34 ounces Incubation is mostly by the female and takes about 24 (robin size). Kestrels, also known as sparrow hawks, have days. rusty red head caps, backs and tails, and a black and white face pattern. Males have blue-gray wings, females brown ) — Length, 15 to Falco peregrinus ( Peregrine Falcon wings. The kestrel is one of our smallest raptor and our 20 inches; wingspread, 38 to 46 inches; weight, 1½ to 2½ most common falcon. Its flight is erratic and buoyant, and pounds. Peregrines, also known as duck hawks, are slate it often perches on telephone poles or hovers in one spot blue, barred darkly above, with a black cap and "mus- killy killy killy. on rapidly beating wings. Voice is a shrill tache" mark below the eye. Young birds are browner and In summer, kestrels take insects and occasionally birds; heavily streaked below. Peregrines have long pointed in winter, they prey mainly on mice. They inhabit open wings and fly with quick rowing wingbeats similar to those woods, orchards and fields, and breed throughout the east- of a pigeon. In attacking prey — ducks, pigeons, blue jays, ern United States. Kestrels nest in tree cavities, aban- flickers and other birds, a peregrine folds its wings close doned woodpecker holes and old buildings, and at times to its body and dives at speeds sometimes more than 175 even nest boxes. Eggs: 3 to 5, whitish, dotted with brown; mph; it strikes with its large knobbed feet, usually break- the female incubates them 29 to 30 days. ing the victim's back and killing it outright. When the Wildlife Notes are available from the Pennsylvania Game Commission Bureau of Information and Education Dept. MS, 2001 Elmerton Avenue Harrisburg, PA 17110-9797 www.pgc.state.pa.us An Equal Opportunity Employer
113 Wildlife Note — 11 LDR0103 River Otter by Chuck Fergus The river otter, Lutra canadensis , is an elusive aquatic adept in water of all the land mammals. It can travel un- mammal. It belongs to the mustelid or weasel family and derwater a quarter-mile without coming up for air, dive is closely related to the sea otter, mink, badger, wolver- up to 50 feet and, if necessary, stay submerged up to four ine and weasels. minutes. While underwater, valve-like structures seal an Otters slide on ice or snow, shoot down slick muddy otter's ears and nose, and its pulse rate drops, slowing banks into creeks, play with food, sticks and stones, and blood and oxygen circulation, making long submersion wrestle each other. Few people are lucky enough to see possible. otters in the wild, but those who do rarely forget the ex- Underwater locomotion is mainly by body movement, perience. with the feet and tail used for steering; propulsion comes from up-and-down body flexing, as opposed to the side- Biology to-side movement of a swimming fish. An otter's top swimming speed is about seven miles per hour. A mature male otter weighs 10 to 25 pounds and is 30 Otters den on the edges of lakes, rivers or streams, or to 40 inches in length, plus a 12- to 15-inch tail. Females occasionally on islands or patches of high ground in are slightly smaller. An otter is muscular, streamlined and marshes. Dens may be excavations under tree roots or solidly built, somewhat like a dachshund; height at the rock piles, abandoned beaver, muskrat or woodchuck shoulder is about 10 inches. An otter's tail is long and burrows, or unused beaver lodges. A typical den has an tapered, thickest where it joins the body and furred its underwater entrance hole, a living space above water entire length. The face is broad, and the eyes protrude level and several air or exit-entry holes to dry ground. slightly. Otters mature sexually by two years of age. They breed Otter fur is a rich dark brown, lighter on the under- sometime between January and May, mating taking place parts; the throat and chin are grayish, the nose black and in the water. As with bare. Two fur layers — short dense underfur and longer many other guard hairs — combine with a subcutaneous layer of fat mustelids, otters to insulate the body. In autumn, the normally thick fur have delayed im- grows in even thicker for extra cold resistance. All four plantation. This feet are wide and webbed between the toes, although the means that after fer- hind pair are used more in swimming than the front pair. tilization, eggs re- Otters obtain most of their food from the water. Fish main dormant in the are favorites: minnows, sunfish, suckers, carp and trout. female's uterus until Other foods are frogs, turtles, snails, mussels (an otter the following Decem- crunches the shells with its teeth), crayfish, snakes and ber, January or Febru- snake eggs, worms, insects, aquatic plants, roots and, on ary, when they attach occasion, muskrats. to the uterine wall An otter's hearing is acute, its eyesight adequate above and start to de- water and superb below. It has a keen sense of smell and velop. Approxi- a set of long, stiff, sensitive whiskers just behind and be- mately two low the nose; these serve as sense organs when the ani- months later, mal is searching for food in murky or turbulent water. from February to An otter is a fast, graceful swimmer, probably the most April, one to five
114 antarctic regions, and desert areas. In North America, (most often two or three) young are born. Females usu- otter populations remain large in the lake region of east- ally have their first litter at age three. ern Canada, Florida, Louisiana, the Carolinas, Alaska, Pups weigh 4 to 5 ounces and are blind and toothless the Pacific Northwest, Michigan and Wisconsin. at birth. They do not open their eyes for five weeks, and In Pennsylvania, the species has been protected since their mother keeps them in the den until they are three 1952, with no hunting or trapping allowed. Because ot- or four months old. The female breeds shortly after giv- ters are secretive and nocturnal, it's hard to estimate the ing birth, but she will not allow a male near her young population. Many of the state's otters are found in our for several months. Males are polygamous. northeastern counties, but they can be found in every When a young otter emerges from the den, its mother major river basin in the state. must teach it to swim. First she carries or pushes the pup Both New York and Maryland have substantial otter into the water; then she submerges, remaining nearby as populations. Their numbers are fairly stable, and trap- the pup tries to swim and letting it climb onto her back ping is permitted in both states. This situation is brought when it tires. After several such lessons, young otters about by the large amounts of suitable aquatic habitat begin to enter the water on their own and eventually play, — numerous lakes in New York, and the Chesapeake and hunt and feed in it. By autumn, they are nearly adult size. seaboard areas of Maryland. They may remain with their mother until she is ready to The Game Commission, Wild Resource Conservation bear another litter. Fund, Pennsylvania State University and other partners Curious and playful, otters romp and wrestle with each have funded otter restocking efforts in the state since other or play by themselves, even as adults. On snow, the early 1980s, and related research and management they take three or four running steps, efforts are ongoing. launch themselves and slide on their Water pollution — strip mine run-off, industrial bellies. While playing, they make wastes, sewage — made many Pennsylvania streams, lakes a variety of sounds: chirps, and rivers unfit for aquatic life, otters included. But much chittering noises and low progress has been made in cleaning up many of the state's chucklings and polluted waterways. A direct benefit of that is the return grumblings. A of river otters. scream is the dan- ger call. Otters Habitat are mainly noc- turnal but oc- Clean water supporting fish and other aquatic life is casionally ven- the foundation of good otter habitat. Although otters ture out during have been sighted miles from water — usually during the the day. breeding season — they were probably en route to an- Otter pre- other water source. dation isn't Otters are found in extremely varied habitat in North common as few America, including high Rocky Mountain lakes, spruce of our predators can and birch forests in the North, marshes and swamps in catch an otter and females go to great lengths to protect the South, and major river basins. their young. Too swift and agile to be caught in the wa- While otters sometimes live near towns and cities, ter, otters are able fighters if cornered on land. They have they seem to prefer wilder territory. Water quality, more tremendous strength, reflexes and endurance, sturdy than any other factor, will determine where otters will teeth and powerful muscles. live in the future. Right now, the future's bright as fish Otters do not store food for winter, nor do they hiber- and other aquatic life are prospering in many of our once- nate. If lakes or rivers freeze, they swim under the ice; polluted waterways. Moreover, tough anti-pollution laws they breathe on the surface of open water, in their dens now safeguard these waters from returning to the crippled or from air pockets lodged against the underside of the state they were in not too long ago. For the otter's sake, ice. In winter, they spend much time in the water, which that's good news and should translate into continuing is often warmer than the air. Otters are more sedentary range expansion for some time to come. in winter than in summer — especially during extreme cold spells — although winter food shortages may force individuals to cover as much as 50 miles of stream over the season. Otters groom themselves frequently and are in the water much of the time, so external parasites are not too common; however, lice have been found on some pelts. Wildlife Notes are available from the Internal parasites include liver flukes and stomach and Pennsylvania Game Commission intestinal worms. An otter's lifespan is 10 to 20 years. Bureau of Information and Education Dept. MS, 2001 Elmerton Avenue Population Harrisburg, PA 17110-9797 www.pgc.state.pa.us Various types of otters are found throughout the world, except in Australia, New Zealand, the extreme arctic and An Equal Opportunity Employer
115 Wildlife Note — 2 LDR0103 Ruffed Grouse by Chuck Fergus Bonasa umbellus, The ruffed grouse, has been flushed from the same area in the woods several days in a Pennsylvania's official state bird since 1931, and its row. beauty is admired by hunter and nonhunter alike. Grouse Grouse eat many types of food. In the summer, they are still fairly plentiful in many parts of Penn's Woods, consume insects (which are rich in protein), blackber- although they're not as abundant today as they were a ries, blueberries and other wild fruits. In fall, when in- hundred years ago. Where mature forests dominate the sects are scarce, their diet is almost exclusively plant landscape, grouse, while present, are limited. But wher- foods including small acorns, beechnuts, cherries, bar- ever brushy conditions are found, there's a good possi- berries, wild grapes, apples, hawthorn and dogwood fruits, bility grouse can be found there, too. and various buds and leaves. Buds form the basis of the Grouse are gallinaceous birds and are related to quail, grouse's winter diet: aspen, birch, beech, maple, cherry turkeys, pheasants and ptarmigan. The ruffed grouse is and apple buds are favored. Ferns, green leaves and other found throughout much of the northern part of our con- evergreen foods are eaten until food becomes more plen- tinent in areas of suitable habitat. tiful in the spring. Like most birds, grouse have keen eyesight and hear- Biology ing. At one time, they were not nearly as wary as they are today; reputedly, early settlers killed them with sticks A grouse weighs about 1½ pounds, body length is 15½ and stones. Today you may surprise a grouse bathing in to 19 inches, and wingspread is 22 to 25 inches. The bird's the dust on a back road, in a sandy bare spot on the for- plumage is rich brown sprinkled with white and black est floor, or in the debris around a rotting stump. Dust above, and white with horizontal dark brown bars on the bathing may stimulate feather growth in young grouse, breast and undersides. The tail is brown and has a wide, maintain adult plumage or rid birds of external parasites. black band between two narrower grayish bands. The Grouse seek shelter beneath conifers during stormy name "ruffed" comes from a ruff of iridescent black feath- weather, and they roost in conifers and hardwoods. They ers that almost completely encircles the neck. may spend winter nights beneath the snow, sometimes Two interesting color phases occur infrequently. flying directly into a soft snowbank at dusk. Grouse are "Silvertailed" birds have gray instead of brown in the not especially gregarious, although groups of birds are tail; "red-ruffs," even rarer than the silver-tails, have rust- sometimes found together in the fall. These are usually a colored feathers with chocolate-brown ruffs and a dark hen and her offspring of that year. During winter, a brown — rather than black — tail band. grouse's feet develop snowshoe-like properties through Males (cocks) differ from females (hens) in several the growth of a horny fringe around the toes. ways. They weigh a little more than females, and have Although its take-off is thunderous and powerful, a much more prominent ruffs, which can be fluffed up for a grouse cannot fly long distances. Its top flight speed is courtship display. The hen has a shorter tail, and her black about 20 m.p.h. After take-off, it flies rapidly and then tail band is generally broken in the center, while the locks its wings and glides to safer territory, usually trav- cock's band is usually continuous. Grouse molt once each eling less than 100 yards. During mating season — March year. Adults molt from July into September and may and April — male grouse attract females by drumming. have difficulty flying when many flight feathers have With tail fanned, the male stands on a large, prominent dropped and replacements have not fully developed. Im- log or rock and beats the air sharply with his wings. The mature birds molt in August and September, when adult rush of air created by his wingbeats sounds much like plumage replaces juvenile feathering. drumming. The drumming starts slowly and increases in Grouse are found throughout Pennsylvania in suitable speed, until the individual thudding beats merge into a habitat and are year-round residents. Individuals rarely fast, steady whir. Males also fight and display for females; range more than a few hundred yards a day unless pressed displaying males fan their tails, puff out their ruffs, hiss by predators or hunters; in fact, the same bird may be and drag their wingtips along the ground.
116 duce undergrowth and cover. Today, good grouse cover A mated hen picks a secluded nesting site, usually at returns wherever forest tracts are cut or burnt off and the base of a tree or under a bush, and lays 6 to 16 white then grow up in brush, duplicating favorable conditions or buff eggs in a leaf-lined depression in the ground. The that were present after the extensive logging of hen may re-nest if nest destruction occurs. The incuba- Pennsylvania's forests around the turn of the 20th cen- tion period is approximately 24 days, and the male does tury. not help the female incubate eggs or brood young. Baby grouse are precocial — they can leave the nest Habitat when dry. Chicks develop rapidly; at three weeks of age they can fly, and by autumn they look and act like adults. Cover is the most important factor affecting the size In early fall, birds of the year may exhibit a strange pe- riod of restlessness known as the "fall shuffle" or "crazy of our state's grouse population. Cover is comprised of physical things that provide natural shelter and protec- flight." During this time, some young grouse take off in tion for wild creatures; grouse need cover for breeding, apparently undirected flight, and a few are killed when they crash into trees, fences, windows and the sides of feeding, wintering and for raising young. Early in the 20th century, much of Pennsylvania provided excellent grouse buildings. The fall shuffle may serve to scatter broods habitat in brushy, logged-off forest areas. Today, these and expand or disperse the population. Grouse rarely — areas have grown up, or matured, and offer less suitable if ever — die of old age in the wild. Juvenile mortality is low cover. great; most grouse die before they are a year old, and few live to be two years of age. Grouse are shy birds and their range has shrunk where cities and towns have expanded; they don't readily adapt Population to civilization. Grouse can do well in areas without vis- ible water sources, obtaining moisture from vegetation Many factors affect the size of the ruffed grouse popu- they eat. They seldom starve during the winter, as they lation. A cold, wet spring following a harsh, long-lasting are capable of "budding" (eating tree buds that are avail- winter results in lower numbers of successful hatches. able regardless of snow depth). Many females succumb to bad weather conditions while The following plant species and situations contribute trying to incubate eggs or brood young, and chicks find to good grouse habitat and should be encouraged: moun- it especially hard to survive cold, drenching rains. Grouse tain laurel and greenbrier thickets, especially those in- can contract diseases which may kill or weaken them, cluding some hemlocks or white pines; prolific sprout making them more susceptible to predation; parasites growth in areas that have been burned or logged within affect grouse similarly. the last 10 years and are growing up again; dense pine Birds may die of a variety of physical accidents, in- clusters in immature hardwood forests; stands of wild crab cluding being hit by cars on back roads. Predation, se- and hawthorn trees; edge provided by logging roads and vere weather and natural disasters like floods and forest trails through wooded areas; and abandoned apple or- fires also contribute to mortality. Hunters harvest only chards near thick cover. Taller trees can be felled to al- what biologists term "surplus" grouse, birds that would low more sunlight to reach grapevines, greenbriers, small die of other causes before the next breeding season. Some conifers, thornapple trees and the like. wildlife biologists estimate that hunters can safely har- Aspen stands can be managed to favor grouse. Aspen vest two out of every five birds present at the beginning has about a 40-year life expectancy and produces a maxi- of hunting season without endangering the next year's mum amount of buds at this age. A percentage of mature breeding stock. In years of good production, hunters usu- trees can be cut every 10 years, producing four different ally take two or three juveniles for every older bird they growth stages in each stand; further segments of each 10- harvest. year stand can be cut every two years to give five ages The grouse population seems cyclic, undergoing fluc- within each stand. These practices result in a variety of tuations — from low to high numbers of birds — that age groups — from one to 40 years old. span periods of five to 10 years. Populations fluctuate Landowners interested in building a good grouse popu- differently in different re- lation should also try to increase the following on their gions, due to local cover, property: juneberries, grapes, greenbriers and witch ha- food, and weather zel. At the same time, they should cull out towering, conditions. Grouse shade-producing trees which may kill the more favor- will not tolerate able low fruiting vegetation. crowding; the minimum area needed to sup- port a single Wildlife Notes are available from the brood is about Pennsylvania Game Commission nine acres. Bureau of Information and Education Pennsylvania's Dept. MS, 2001 Elmerton Avenue rapidly maturing Harrisburg, PA 17110-9797 forests and large www.pgc.state.pa.us deer herd have combined to re- An Equal Opportunity Employer
117 Wildlife Note — 31 LDR0103 Shrews by Chuck Fergus Although most people never see one, shrews are plen- Active year-round, shrews have terrific metabolic rates tiful animals that play an important role in nature. Shrews and must eat almost continuously. They are quick and belong to the order Insectivora, a diverse group consid- aggressive and may attack animals larger than themselves. ered the most primitive of the true placental mammals. At least one species of shrew has poisonous saliva, a rare As their name suggests, Insectivores feed mainly on in- example of toxicity in mammals. Delivered with a bite, sects. Shrews do most of their feeding above ground or the toxin slows down or kills prey, and can cause sore- in tunnels in the leaf mold and debris right at the ground's ness and swelling in humans. surface. They are related to moles, insect-eaters that live Shrews are short-lived. They die from floods, starva- deeper in the soil. tion, rapid temperature changes, accidents, fights with Shrews range in size from the pygmy shrew (a little other shrews and even from shock due to fright. Many over three inches long, weighing 0.08 to 0.13 ounces) to predators catch and kill them, perhaps in mistake for the short-tailed shrew (4 to 5 inches long, 0.44 to 0.82 mice, but because shrews secrete a repelling musky odor, ounces). In each of the seven shrew species inhabiting predators often do not eat them. Pennsylvania, the sexes are equal in size and weight. Shrews raise several litters each year. Gestation is Shrews have long, pointed noses, beady eyes and slen- about three weeks. Newborn young are helpless and der skulls. Their small ears are covered (or nearly so) by unfurred, but grow rapidly and reach adult size when 4 short, velvety fur. Here's how to tell one from a mouse: to 6 weeks old. For more specific life history informa- shrews have five toes on each foot (most mice have four tion, see listings under each species. toes on their front feet); shrews' teeth are sharp and pointed, and often stained dark (mice have chisel-like Sorex cinereus Masked Shrew ( ) — The masked shrew cutting incisors typical of rodents, without the dark stain- is the most widely distributed shrew in North America, ing); and shrews' eyes are beadier and their noses more ranging over almost all of the continent's northern half. pointed than those of mice. Most Pennsylvania shrews It occurs throughout Pennsylvania. Overall length, 3.3 look fairly similar, and it often takes an expert to tell to 4.3 inches; tail, 1.4 to 1.8 inches; weight, 0.12 to 0.2 them apart. ounces (less than a dime). Masked shrews molt twice a year. In winter, they are dark brown to almost black on their upperparts, lighter brown or grayish on their underparts. Summer colora- tion is lighter and browner. Sorex cinereus closely re- sembles the slightly smaller pygmy shrew. Short-tailed Masked shrews inhabit wooded areas, living under rocks logs and in the leaf litter, often in swamps or along Shrew stream banks or spring runs. Rarely found in dry fields, they occasionally inhabit hedgerows and stone walls in open country. Masked shrews spend most of their lives in underground runways they construct, or in the tun- nels of mice or other small mammals. Masked shrews sometimes climb into low bushes or fallen trees. They are good swimmers but rarely enter the water. Their ability to see and smell are poor, but their sense of touch is well-developed. Masked shrews eat insects, worms, centipedes, slugs,
118 mer, and an overall slate gray in winter. Total length, 3.9 snails, mollusks and spiders, vegetable matter such as to 5.3 inches: tail. 2 to 2.3 inches: weight. 0.14 to 0.21 moss and seeds, and carrion. They probably do not store ounces. food. One observer reported that a captive ate over three Foods include small invertebrates and plant materi- times its body weight daily. als. Little is known of the life history of this shy species, The species nests under logs, stumps or rocks, in fist- but it is probably similar to those of the masked shrew size nests of leaves, grass and fine rootlets. Breeding runs and smoky shrew, which often share the same habitat. from March to September. After an 18-day gestation, 2 to 10 (usually about 7) young are born. They are blind Sorex hoyi and helpless but grow quickly and are on their own after Pygmy Shrew ( ) — The pygmy shrew ranges about a month. They mature sexually at 20 to 26 weeks across much of northern North America. It occurs in of age. An adult female may raise three litters; the male northern and western Pennsylvania, but records are remains with the family during the early life of the young. sparse. Masked shrews are active day and night, but especially This is the smallest mammal in Pennsylvania and one of the smallest in the world. Overall length, 3.2 to 3.8 at dusk. An individual's heart beats 1,200 times per inches; tail, 1.1 to 1.3 inches; weight, 0.08 to 0.13 ounces minute, evidencing its rapid metabolism. Owls, hawks, — about half that of a large earthworm. In the field, the herons, shrikes, weasels, foxes, cats and the larger shrews kill masked shrews, few of which reach their maximum pygmy shrew is almost impossible to distinguish from a small masked shrew. lifespan of about 18 months. Pygmy shrews often live in wet or closely mingled wet and dry habitats. They live under old stumps and rotting ( Sorex fumeus ) — The smoky shrew oc- Smoky Shrew logs, among the litter in sedges, ferns, aspen clumps, and curs throughout the Northeast from Nova Scotia to hardwood forests, and in heavy conifer stands bordering North Carolina. It inhabits most of Pennsylvania but is water. scarce in southwestern and southeastern counties. We know almost nothing about the species' life his- Coloration is a uniform dull brown, except for the bi- tory, but it is probably similar to those of other long- colored tail, brown above and yellowish below, and pale tailed shrews (long-tailed, smoky and masked shrews). buffy feet. In summer, the fur is slightly darker and browner. The smoky shrew resembles the masked shrew Short-tailed Shrew Blarina brevicauda ( ) — The short- but is larger, stouter and darker. Overall length, 3.7 to 5 tail is one of the commonest shrews and most abundant inches; tail, 1.4 to 2 inches; weight, 0.21 to 0.35 ounces, small mammals in its range. It inhabits the eastern United about one-third the weight of a house mouse. States from southern Canada to Florida, and occurs state- The smoky shrew prefers cool, damp woods with deep wide in Pennsylvania. leaf litter. Prime habitats include deep, shaded hemlock This shrew is dark slate above and paler below, slightly ravines, northern hardwood forests, spruce and sphag- lighter in summer than in winter. It is the largest and most num bogs, and stream borders with moss-covered boul- robust of Pennsylvania shrews. Overall length, 4.1 to 5.2 ders and logs. inches; tail 0.7 to 1.2 inches: weight 0.44 to 0.82 ounces. Smoky shrews may be active at all hours. They bur- Short-tailed shrews live in almost all habitats: woods, row through the leaf mold or travel in other animals' tun- banks of small streams, tall grass and brush. They fre- nels. They eat insects, salamanders, snails, worms, spi- quent the top few inches of soil and leaf litter, digging ders and small birds either alive or as carrion. their own tunnels or using those of mice, voles and other These shrews build baseball-size nests of dry vegeta- small mammals. They burrow through the snow in win- tion deep within rocky crevices or stone piles, or under ter. Home range is a half-acre to an rotting logs, stumps or boards. They breed from late acre. Active day and night, short- March into August. Females bear up to three litters an- tails eat insects, worms, snails, nually, of 2 to 8 (usually 5 or 6) young. Offspring are salamanders, small snakes, independent by one month of age. songbirds, mice, voles, Smoky shrews appear to be social animals, with popu- other shrews, lations fluctuating from year to year. They fall prey to carrion short-tailed shrews, weasels, foxes, bobcats, hawks and owls. Maximum lifespan is about 17 months. ) — The long-tailed Sorex dispar ( Long-tailed Shrew shrew inhabits the Appalachian Mountains from Maine Water to North Carolina. It occurs throughout Pennsylvania, Shrew except in the extreme southeast and west. likes cool, damp forests, deciduous or Sorex dispar mixed. It is also called the rock shrew, since its pre- ferred habitat is rock-slides, where it lives in natural tunnels among the jumbled boulders. In Pennsylvania, the species prefers moun- tain slopes. Long-tailed shrews are dark gray with slightly paler underparts in sum-
119 underground or beneath logs, stumps or debris. They breed from March through Masked Shrew November. Three to six blind, hairless young are born following a gestation pe- riod variously reported as 15 to 23 days. Several litters may be raised each year. Both parents care for the young, which are weaned at 21 days. Longevity is less than two years. and vegetable matter. Individuals cache food in small Water Shrew ) — The water shrew in- Sorex palustris ( chambers in their burrows. habits much of northern North America. In the East, it The short-tailed shrew has poor eyesight, a fair sense ranges from New England to North Carolina. It is found of smell and keen hearing and touch. It possesses poison- across Pennsylvania's northern half, and south through ous saliva but lacks an efficient injection system, so the the Appalachians. toxin must get into a prey animal through cuts caused by Sorex palustris is the second largest Pennsylvania shrew the shrew's sharp teeth. The toxin slows down or kills (the short-tailed shrew is more robust). Overall length, warm-blooded prey. 5.3 to 6.1 inches; tail, 2.4 to 3.5 inches; weight, 0.35 to Blarina brevicauda weaves dry plant materials and hairs 0.6 ounces. In winter, the pelt is brownish-black above into two types of nests, a resting nest and a larger mating (sometimes faintly grizzled with silver) and light gray be- structure, beneath logs, stumps, rocks and debris. Breed- low. In summer, the upperparts are browner and the un- ing may begin as early as January; 3 to 10 young (usually derparts paler. The long tail is brownish-black above, 5 to 7) are born 21 days later and are on their own at 25 paler below. days of age. Two or three litters may be raised per year. The water shrew inhabits heavily wooded areas and is Foxes, dogs, bobcats, cats, skunks, weasels, hawks, owls adapted to a semi-aquatic life. The banks of cold, clear shrikes and snakes kill short-tailed shrews. The average streams provide optimum habitat. Water shrews occupy lifespan is 18 to 20 months. small surface runways under bank overhangs, fallen logs and brushpiles. They also live in bogs and springs, and Cryptotis parva ( ) — The least shrew lives Least Shrew may shelter in a beaver lodge or muskrat house in winter. in the southeastern and central United States, north and Nests are usually made of dry moss. east into New York. It's found statewide in Pennsylvania. This shrew uses its big hind feet, fringed with short, Coloration is cinnamon to brown above, ashy gray below, stiff hairs, to paddle about under water. It can stay sub- darker in winter than in summer. Overall length, 2.7 to merged about 15 seconds. Water cannot penetrate the 3.5 inches; tail, 0.47 to 0.78 inches; weight, 0.14 to 0.2 shrew's dense pelage, so the animal itself never gets wet. ounces. A water shrew can run short distances across the water's Favored habitats are open, dry situations, such as old surface, buoyed up by globules of air like a water bug. pastures or meadows, or along woodland edges. Least Water shrews locate aquatic prey by touch. They eat shrews are scattered in local colonies throughout suit- insects and other small invertebrates (both aquatic and able habitat. More convivial than most other shrews, which terrestrial), small fish and fish eggs. tend to be belligerent toward others of their own species, Little is known about the breeding habits of this secre- least shrews may nest in groups of a dozen or more, espe- tive species. The gestation period is about three weeks, cially in winter. with 4 to 8 young born from late February to June. Fe- Least shrews are active at all hours, but mainly at night. males probably bear more than one litter each year. They travel their own or other small mammals' runways Water shrews tend to be nocturnal but are also active and burrows. They eat insects, earthworms, centipedes, at dusk, on cloudy days, and in the shade on sunny days. millipedes, snails, mollusks, frogs and carrion, and they Predators include weasels, mink, otters, hawks, owls, drink water freely. snakes and fish (smallmouth bass, trout and pickerel). Lon- Least shrews build nests of dried grass or leaves, either gevity is about 18 months. Wildlife Notes are available from the Pennsylvania Game Commission Bureau of Information and Education Dept. MS, 2001 Elmerton Avenue Harrisburg, PA 17110-9797 www.pgc.state.pa.us An Equal Opportunity Employer
121 Wildlife Note — 62 Snow Ldr1204 Goose By Chuck Fergus Chen caerulescens , is one of the world's The snow goose, most abundant waterfowl species. Snow geese breed in the eat leafy parts of grasses, sedges, rushes and other aquatic arctic and subarctic regions of North America during spring plants, and grub out the roots and tubers of a variety of land and summer, then migrate south to spend the winter in in- plants and shrubs. En route to and on the southern wintering land and coastal areas, including Pennsylvania. They feed grounds, they dine on aquatic grasses, sedges and rushes; ber- voraciously on vegetation, and recent population increases ries; corn, wheat, barley and other grains gleaned from har- have led to serious damage of the species' habitat, mainly on vested fields; and pasture grasses and leafy stems of crops its breeding range, but also in some wintering areas. such as winter wheat and rice. In winter, snow geese feed from two to more than seven hours per day. In spring, when Biology building up fat reserves for migration, they may feed more A medium-size goose, the snow goose is 27 to 33 inches than 12 hours daily. long, with a wingspread of about 54 inches. It has a chunky Males and females establish lifelong pair bonds. Most body and weighs from 3.5 to 7 pounds, with males slightly snow geese choose mates having the same color as the family heavier than females. in which they themselves were reared. Individuals pair up has two distinct subspecies, the greater Chen caerulescens during their second winter or on their second northward snow goose and the lesser snow goose. The lesser snow goose migration, when they are almost two years old; generally is dimorphic, meaning it comes in two color phases, white they first breed successfully at age three. During courtship, and blue. The white phase is all white with the exception of the male puffs up his body and stands in an exaggeratedly black primary wing feathers. On the blue phase, the head straight and tall posture. Males and females display to each and front of the neck are white, and the body is gray-brown, other by raising the head and neck, calling vociferously and with white or gray underparts. Intermediate color forms also flapping their wings. Mating takes place in shallow water occur. All snow geese have, in addition to black primaries, a and on land. black patch on the edge of the bill, suggesting a grin when Snow geese nest on arctic tundra, near river mouths and viewed from the side. The eyes are dark, the bill is pink, and on islands, usually within five miles of the coast. They gather the legs are dark pink. White individuals sometimes show in colonies varying greatly in number and density of pairs. A rust-colored stains on the head and neck, caused by the birds' pair defends an area around its nest, where both partners grubbing for food in muddy ground. feed heavily. The female builds a shallow nest out of plant It is primarily the greater snow goose that winters in Penn- material and down plucked from her body; she may reuse sylvania. The lesser snow goose's U.S. wintering range has her previous year's nest. Nests are often sited on low ridges or traditionally been a column sweeping from north to south hummocks offering good visibility over the surrounding ter- through the Midwest part of the country, not reaching as far rain. A female typically lays three to five creamy white eggs, east as Pennsylvania. As the range of the lesser snow goose sometimes as many as seven. Incubation is by the female expands, however, blue phase geese are being seen infre- alone, with the male remaining close to the nest. Sometimes quently on Pennsylvania wintering grounds. one pair may trespass in another pair's territory; while the Snow geese are good swimmers. They do not normally resident male is occupied in driving off the intruding male, dive to find food, but can submerge to evade predators. the intruding female tries to lay an egg in or near the resident They walk readily on land, and run swiftly. They sleep float- female's nest. Because unattended eggs attract predators, a ing on the water, or on land, sitting down or standing on one female will usually roll a deserted egg into her own nest, leg; the head is held low or tucked partway beneath one which can lead to her rearing another female's young. Biolo- wing. Strong fliers, snow geese can reach speeds of 50 miles gists describe this phenomenon as "nest parasitism." Chen caerulescens is extremely vocal. Individuals per hour. Main nest predators are foxes, gulls and parasitic jaegers. kowk or whouk sound a , given repeatedly in flight and on the Bears, wolves and ravens also take some eggs. Eggs hatch ground and resembling the shrill barking of a dog. When after 22 to 23 days of incubation. The goslings emerge wet, feeding, snow geese make quieter gah notes. Parent birds but dry within four hours beneath the brooding female. Gos- vocalizations to their goslings. uh-uh-uh utter lings are able to walk, swim, dive and feed soon after they Snow geese feed in shallow water and on the ground, leave the nest, usually within hours of hatching. typically in saturated soil. On their breeding grounds they Both parents help raise the young. A family may walk
122 geese is the Game Commission's Middle Creek Wildlife Man- more than two miles per day between food sources and up to agement Area in Lancaster County, where up to 150,000 45 miles during the brood-rearing season. Goslings graze on birds have been seen. In autumn, the greatest numbers of vegetation, and also eat some insects. They grow rapidly, snow geese pass through Pennsylvania in November. Each gaining around 5.5 ounces per day. Goslings are taken by year, weather conditions and food availability influence mi- gulls, foxes and snowy owls; adults are occasionally preyed gration dates. on by foxes, wolves, bears and eagles. Snow geese can live beyond 26 years. Individuals perish The young begin to fly 42 to 50 days after hatching. They from avian cholera, hitting power lines in flight, hunting stay with their parents while migrating south for their first and predators. Predators on the wintering range include coy- winter. The family remains intact through the winter and otes, foxes and eagles. during the migratory journey north again in spring. After arriving on the breeding grounds, the family breaks up and Habitat the adults begin rearing another brood. In summer, snow geese nest along braided river mouths, During migration, snow geese fly both by day and night. on islands and in sections of arctic tundra studded with In fall, they often travel in large flocks with more than 1,000 ponds. Many of the greater snow geese that winter in Penn- members; spring flocks vary in size from a few dozen to a few sylvania nest in the eastern high arctic, with Baffin and Bylot hundred individuals. Usually they migrate along fairly nar- islands containing the largest colonies. They favor areas that row corridors, with traditional stopping points along the become clear of snow early in the year and do not flood way. Migrating snow geese take advantage of following winds, during the spring thaw. Parents lead their goslings to food- good visibility and periods of no precipitation. They fly in rich areas — damp meadows, edges of freshwater lakes and long, diagonal lines and in V-formations, at altitudes of up ponds and tidal marshes. During migrations, snow geese fre- to 7,500 feet. When preparing to land, they may tumble to quent freshwater and brackish marshes, slow-moving rivers, lose height in what has been described as a "falling-leaf" lakes, ponds and farm fields. Winter habitats include coastal maneuver. marshes, wet grasslands and agricultural fields. Pennsylvania The species' breeding range extends from Alaska east to is attractive to snow geese because of the large number of western Greenland. Biologists recognize three separate popu- agricultural fields. Waste grain left after havesting allow birds lations. The western population breeds in Alaska and to recharge fat reserves needed for spring migration and nest- Canada's Yukon, Northwest and Nunavut territories and win- ing and, thus, has been implicated in increasing survival ters from Oregon south to Mexico, with concentrations in rates. At times, snow geese can be destructive feeders, pull- the central valleys of California. The midcontinent popula- ing stems and roots of plants out of the ground. This grub- tion breeds from Nunavut Territory east to Hudson Bay and bing behavior is largely responsible for extensive habitat winters in the U.S. Midwest south to Louisiana and Texas. damage of marsh habitats on both breeding and wintering The eastern population breeds on islands in the High Arc- areas. tic, including Ellesmere and Baffin then winters along the Atlantic Coast from Massachusetts to South Carolina, with Population concentrations in southeastern Pennsylvania, New Jersey, had Chen caerulescens Around 1900, the population of Delaware, Maryland, Virginia and North Carolina. In win- ebbed to only 2,000 to 3,000 birds. During the 20th century ter, snow geese are highly gregarious and often feed in flocks and into the 21st century, the population has burgeoned as numbering thousands of individuals. snow geese have begun taking advantage of farm crops, in- Migrants follow all four major North American flyways. cluding waste grain, along migration routes and in wintering Migration north from wintering areas. In some areas, populations have increased as much as areas takes place from Feb- 9 percent per year. Biologists estimate that there are now 5 to ruary to May. In autumn, 6 million snow geese in North America, a population that snow geese de- may be too large to be environmentally sustainable. part from Each year, wintering populations vary in abundance, de- the north- pending on nesting conditions in the arctic (cold, wet ern breed- weather may drastically lower breeding success); the avail- ing areas in ability of food on breeding grounds, staging areas and stop- September and ar- over points along migration corridors; and hunting pressure. rive in wintering Harvest estimates since 1998 indicate that from 1 to 1.5 habitats in Novem- million birds are harvested annually. Recent conservation ber and December. hunts implemented in Canada and the U.S. have been suc- In Pennsylvania, cessful in doubling the harvest rates of snow geese and bring- snow geese are seen ing down the populatons of both lesser and greater snow more frequently in geese. When snow geese populations are too large, the birds' spring than in fall. feeding can destroy their own habitat, which is also used by They pass through other species. the state from about Wildlife Notes are available from the the third week of Feb- Pennsylvania Game Commission ruary to the first week of Dept. MS, 2001 Elmerton Avenue April, with a peak in early Harrisburg, PA 17110-9797 to mid-March; an excellent www.pgc.state.pa.us place to view migrating snow An Equal Opportunity Employer
123 Sparrows Sparrows Sparrows Sparrows Sparrows Wildlife Note — 45 and and and and and LDR0103 owhee owhee T T owhee T owhee owhee T T White-Crowned by Chuck Fergus Sparrow At first glance, sparrows (Family Emberizidae) may seem nogamous, but the breeding biology of many species hasn't to be drab, ordinary birds. Because of their apparent been studied carefully enough to allow definite conclusions. sameness — as well as the dense or grassy cover in which In the savannah sparrow, males may have two mates whose most are found — beginning and casual birdwatchers may broods are staggered, so that the male can help first with find it tough to identify the different species. In fact, the one brood and then with the second. Some male swamp plumage of each is a distinctive, complex blending of shades sparrows also have two mates. and streakings of brown, and the birds' habits and adapta- Sparrows do not make long migrations. Most species tions work in fascinating ways to let them take advantage winter in the southern United States and northern Mexico, of many habitats. "Sparrow" comes from spearwa , an and none go as far as the tropics. In winter, sparrows are Anglo-Saxon word meaning "flutterer"; English settlers often gregarious and travel in flocks when searching for food. applied the name to New World sparrows. (In England to- In open country, flocks often contain individuals of only day, birds we would call sparrows are referred to as bun- one species, but in brushy areas or along woods edges, which tings.) More than 30 species are native to North America. offer a more diverse suite of foods, mixed-species flocks are Eleven breed in Pennsylvania, and five more cross the state the rule. By far the greatest threat to sparrows is the de- when migrating. struction of their habitat. Draining swamps and converting Sparrows have short thick bills for cracking the hard seeds fields to housing developments relentlessly cuts into the of grasses, weeds and trees. Most forage on the ground, size and diversity of sparrow populations — as well as harm- scratching with their feet to expose food in dense grass and ing many other kinds of wildlife. weeds and in low shrubs. They keep in contact with mates A closer look at five common Pennsylvania spar- or or flock members by using short calls, often chip seep rows follows. sounds, which vary between species. Sometimes sparrows make short flights to catch flying insects that they've flushed from the ground. Adults eat insects in summer and nourish their young with this high-protein fare. In late summer and fall, sparrows eat berries and fruits. And they eat many seeds, Eastern Towhee especially those of grasses and weeds. Males defend territories mainly by singing from exposed perches, and their songs are often complicated and mellif- luous. The males of some grassland sparrows perform flight-and-song displays. Males also chase away rivals. In most species, pairs nest in isolation or in loose colonies brought together less by social tendencies than by attrac- tion to a special habitat. Sparrows usually nest in low bushes or on the ground. The typical nest is an open cup woven out of grass, weeds and twigs, built mostly or entirely by the female. The eggs of the various Northeastern sparrows are spotted or blotched with brown. In most species, the fe- male incubates the eggs; the male may bring food to her. Both parents share in feeding the young. Should a female begin a second brood, her mate may assume the care of first-brood young that have fledged from the nest. Ornithologists believe that most sparrow pairs are mo-
124 Chipping Sparrow brown spotting. She incubates them for 12 to 13 days; dur- ing the day, she sneaks off to feed about once every half hour. After the eggs hatch, the male brings food for the brooding female and the young. In about a week the female begins leaving the nest to help the male forage and feed the brood. Young leave the nest after 10 to 12 days, and their parents feed them for another month. Most females build a second nest, and most pairs produce two broods. In Penn- sylvania, towhees nest from late April into August. After fledging, young birds flock together; adults do not defend their territories against juveniles, even if not their own. In winter towhees shift southward into the southern states, where they forage in loose flocks averaging 15 to 25 members. Females go farther south than males. The esti- mated life span is four to six years. The clearing of the East- ern deciduous forests around the turn of the century helped towhee populations to expand. More recently, as old fields have matured into woods, the population of this species has declined noticeably. Pipilo erythrophthalmus ) — Formerly Eastern Towhee ( called the rufous-sided towhee, this large (seven to eight Chipping Sparrow ( Spizella passerina ) — This small, slim inches), long-tailed sparrow breeds statewide in Pennsyl- sparrow is about five inches long and marked with a rusty- vania. Adults have rusty sides, white bellies, and colored cap and a line of white above each eye. The Penn- solid-colored backs and heads that are black in the male sylvania breeding bird atlas survey found the chipping spar- and brown in the female. The eyes are red. Males sing a row to be the fourth most widespread bird in the state; only distinctive drink your tea , with the middle syllable low and the song sparrow, crow and robin were observed more fre- the last syllable drawn out and quavering. Both sexes fre- quently. Chipping sparrows feed and breed in suburbia, ur- call. A way to or quently give an emphatic chewink tow-hee ban parks, gardens, clearings around rural homes, pastures, locate the birds is to listen for the rustling they make while orchards, shrubby fields, open woodland and woods edges, scratching for food in the leaf litter. The eastern towhee is in openings and roadsides within the deep woods. On a sometimes called the "chewink," for its call, and "ground continental scale, they breed from Alaska to Nova Scotia robin" for its foraging habits. Eastern towhees are found mainly in second-growth for- ests, overgrown fields, woods edges, clearcuts, hedgerows, thickets, dense brush, and the understory of open decidu- ous woods. Rarely do they live in suburban yards, cities or intensively farmed areas. When seeking food, towhees en- ergetically turn up leaves by hopping backwards, scratch- ing with both feet. They pick up beetles, ants, bugs, spiders, millipedes and snails; they eat caterpillars (including late-stage gypsy moth larvae) and moths (adult gypsy moths and others); and they dine on seeds, small fruits, berries and acorns. In April, males arrive in the north in small bands; they disperse and, singing from high perches, proclaim individual territories of one-half to two acres. Females show up about a week later. Males and females spread their wings and tails to each other, exhibiting their white patches. The female gathers materials for the nest, while the male sings nearby. She scuffs out a shallow depression in the ground and builds a bulky but well-camouflaged nest of leaves, bark strips and other plant matter, lined with fine grasses and pine needles. Occasionally the nest is built in a bush, as high as five feet above the ground. The female lays three or four eggs, creamy white with Field Sparrow
125 Song Sparrow and south to Nicaragua. They are not very shy of humans. The song is a rattling or buzzing trill: a series of chips in one pitch. Chipping sparrows forage in trees and on the ground. Their diet in early summer may be 90 percent insects, in- cluding grasshoppers, caterpillars, beetles and moths. They eat many seeds, especially in fall and winter, of chickweed, pigweed, ragweed, foxtail and other grasses. Males arrive on the breeding range in April, ahead of females, and claim territories of one half to one and a half acres. In early May the females build nests, often in conifers (including subur- ban plantings) 3 to 10 or more feet above the ground. A female usually lines her nest with fine grasses or animal fur, including horse hair. The three or four eggs are a pale bluish green, marked with brown spots. The female incu- bates the eggs for 11 to 14 days; young fledge from the nest eight to 12 days after hatching. Chipping sparrows are believed to be monogamous breeders. Most pairs raise two broods per summer. In August and September, family flocks desert their home territories and wander while searching for food. In late Sep- swee-swee-swee-swee- notes speeding up into a trill tember and October, most chipping sparrows leave the . Field sparrows live in old fields with scat- wee-wee-wee-wee Northeast for wintering grounds in the Gulf States. In the tered brush and bramble and sumac clumps, in thickets, 1800s the chipping sparrow was the common sparrow of fencerows, and Christmas tree plantations; they avoid open American towns and cities, but the introduced house spar- meadows, cropland, urban areas and deep woods. The spe- row largely took over that role. Chipping sparrows are preyed cies breeds in every Pennsylvania county but is absent from upon by blue jays, snakes, domestic cats, and the smaller heavily developed areas around Lancaster, Philadelphia and hawks and owls; brown-headed cowbirds often parasitize first Pittsburgh. It ranges across the East and winters from south- broods, but chipping sparrows raise their second broods af- ern Pennsylvania southward. ter the cowbirds' annual breeding period has ended. Field sparrows arrive in their breeding habitat in mid- April. Males' territories average two to three acres. ) — Like the closely related ( Field Sparrow Spizella pusilla Females build their nests on or near the ground for the chipping sparrow, the field sparrow has a chestnut-colored season's first brood, then often select a thick shrub, such as a cap; however, it lacks a white facial stripe and has a notice- hawthorn, for a second-brood nest. The three to four eggs ably pink or rusty colored bill. The song is a series of sweet hatch after about 11 days of incubation. Unlike chipping sparrows, field sparrows rarely nest near human dwellings; like chipping sparrows, field sparrows permit people to come quite close. Field sparrows migrate south in September and Spizella pusilla was first described and named by or- October. nithologist Alexander Wilson on the basis of specimens col- lected around Philadelphia. ( Geothlypis trichas ) — An accomplished Song Sparrow songster, this shy sparrow has a heavily streaked breast with a dark central spot. When in the species' habitat of over- grown weedy areas, thickets or abandoned pasture land, lis- ten for the melodious song: three or four repeated notes, sweet sweet sweet sweet , followed by a number of shorter vari- able notes and a trilled ending. Song sparrows breed across North America and winter in the lower 48 states. They breed statewide and abundantly in Pennsylvania; more song spar- rows winter in the southern half of the state than in the northern half. Corn stubble and brushy thickets are prime wintering areas. Song sparrows nest mainly on the ground in grasses, sedges Tree Sparrow
126 and cattails, with later nests often located in trees or bushes up to 12 feet high; on rare occasions, song spar- rows nest in tree cavities. Prolific breeders, they may raise two, three or even four broods per season, sometimes all in the same nest. The normal clutch is four eggs. The eggs of brown-headed cowbirds look very much like song spar- rows' eggs (greenish white, heavily dotted and blotched with reddish brown) and, except for the yellow warbler, the song sparrow is the most frequently reported host for the parasitic cowbird. The song sparrow population in Pennsylvania seems to be stable or rising slightly. Junco hyemalis ) — Juncos are famil- ( Dark-Eyed Junco Dark-Eyed Junco iar winter visitors; many people are surprised to learn that juncos breed in Pennsylvania, too. These birds have slate-gray backs and heads, white bellies, pink bills, and white outer tail feathers. The springtime song is a slow musical trill similar to that of the chipping sparrow; what's usual in winter is a string of twittering notes. Ground-loving birds, Six other sparrows breed in Pennsylvania. The vesper juncos scratch in the leaf duff, soil and snow to expose their ) is a grassland species that Pooecetes gramineus sparrow ( food. In summer, insects make up about half of the diet. breeds in scattered locales across the state; its numbers have Seeds of ragweed, foxtail, crabgrass, smartweed, pigweed, and declined in the last 30 years. The shy, inconspicuous savan- other grasses and weeds predominate in fall and winter. Jun- nah sparrow ( Passerculus sandwichensis ) nests on the ground cos also eat springtails, the tiny "snow fleas" that pepper the in open grassy areas such as meadows, hayfields and reclaimed snow on warm winter days. surface mines. Another species inhabiting grasslands and Juncos breed across northern North America and south meadows is the grasshopper sparrow ( Ammodramus in the Appalachians to Georgia. In Pennsylvania they nest savannarus ). Henslow's sparrow ( Ammodramus henslowii ) on wooded ridgetops and in hemlock ravines across the for- breeds mainly in western Pennsylvania, in abandoned weedy ested northern third of the state. In spring, males stake out fields, damp meadows and reclaimed strip mines. The swamp breeding territories of two to three acres, singing from tall Melospiza qeorgiana sparrow ( ) is found in Delaware River tidal trees — about the only time these birds ascend very far from marshes, in freshwater marshes in the state's northeastern the ground. Breeding runs from April into August. Females and northwestern quadrants, and elsewhere in bogs, swamps, build nests on the ground: on vegetated cutbanks of logging and rank growth adjoining ponds and sluggish streams. The roads, stream banks, and hillsides, or tucked beneath ex- ) breeds mainly white-throated sparrow ( Zonotrichia albicollis posed tree roots overhung by dirt or plants. The three to six in the north, often in or near forested wetlands, and its range eggs are pale blue profusely dotted with brown. Some pairs extends south into Pennsylvania's northern tier; this chunky, raise two broods. Juvenile birds are streaked with brown. colorful sparrow is also frequently seen during migration. Juncos move south in flocks, mainly in October. The in- dividuals we see wintering in Pennsylvania probably bred or As well as the above-mentioned species, other sparrows were hatched farther to the north. Winter flocks tend to move through Pennsylvania in spring and fall. The Ameri- have same-age, same-sex members; each flock numbers Spizella arborea can tree sparrow ( ) is a common migrant and around 15 to 30 birds who forage together on an area of 10 Passerella iliaca ) and a winter resident. The red fox sparrow ( to 12 acres. In winter, juncos favor hedgerows, brush piles, white-crowned sparrow ( Zonotrichia leucophrys ) also may thickets, weedy fields and shrubbery around houses. At night, winter in Pennsylvania. The saltmarsh sharp-tailed sparrow flock members roost together in a habitual site, usually in ( Ammodramus caudacutus ) and Lincoln's sparrow ( Melospiza the dense boughs of a conifer. ) migrate through our state. lincolnii Wildlife Notes are available from the Pennsylvania Game Commission Bureau of Information and Education Dept. MS, 2001 Elmerton Avenue Harrisburg, PA 17110-9797 www.pgc.state.pa.us An Equal Opportunity Employer
127 Wildlife Note — 1 LDR0603 Squirrels by Chuck Fergus Most Pennsylvanians are familiar with the gray squir- Gray squirrels eat mast — acorns, hickory nuts, wal- rel, which lives both in towns and rural areas. The gray is nuts and beechnuts. Other foods include berries, mush- our state's most common rooms, pine seeds and corn (only the germ at the base of squirrel; the fox, red the kernel is eaten), and dogwood, wild cherry and black and flying squirrels are gum fruits. three other species na- In early spring, squirrels eat buds, a high-energy food. tive to our state. They eat the buds and flowers of red and sugar maples in Squirrels are fast and April, and later may feed on the winged fruits of red agile, scaling trees and maple. These foods have a high moisture content that jumping from treetop supplies squirrels' water needs, although grays will drink to treetop with great from available ground water sources. Grays smell out nuts speed. When jumping, they they have previously buried for winter food. Unrecov- use their large tails to help ered nuts may sprout and grow into trees. In this way, keep balanced. squirrels help ensure continual forest growth. Squirrels see only in Grays are probably the wariest of Pennsylvania's squir- shades of black and white, rels. They're quicker than fox squirrels and less vocal but their eyes are than reds, although they sound warning barks and assorted sharp and detect "chucks." Hawks, owls, foxes and tree-climbing snakes movement well. occasionally kill young squirrels, but adults are not eas- They have keen ily taken. Predators do not appreciably affect squirrel senses of hearing populations on good ranges — availability of food is the and smell. They are key to population size. most active in early A maximum life span for a wild gray squirrel could be mornings and late afternoons, ex- 10 years or even longer, but few live more than two or cept the nocturnal flying squirrel. three years. Grays live in nests and dens. They build leaf Squirrels are rodents, and the four nests in trees near good food supplies in both summer species do not interbreed. Born blind and hairless, young and fall. The leaf nests are cooler than tree dens, they're are dependent upon their mother for up to two months. about 12 by 16 inches and are built of twigs, leaves, grass, bark and other plant materials. Tree dens are often in Biology cavities where limbs have broken off or in deserted wood- pecker holes, usually 40 to 60 feet off the ground. Resi- ( Gray squirrel ) — Adult gray Sciurus carolinensis dent squirrels gnaw back the outer tree bark that, in time, squirrels weigh 1 to 1½ pounds and are 18 to 20 inches would otherwise seal off den holes. in length; about half this length is a broad, bushy tail. Gray squirrels breed in late winter or early spring. Most grays are colored silvery-gray above and off-white Following a 44-day gestation period, females bear litters below, often with rusty or brownish markings on the sides of 4 to 5 young in late February, March or early April. or tail. Albinism is rare, but melanism (black coloration) The young are usually raised in tree dens and nursed by is fairly common. Once, black-phase gray squirrels were their mother for 5 to 7 weeks. Gray squirrels often bear a found throughout Pennsylvania; today they occur most second litter in July or August, and small grays seen in often in the northcentral counties. "Black squirrels" may autumn are from summer litters. Grays are gregarious and be any shade from dark gray to nearly jet black, often do not seem to demonstrate territoriality. Three or four with a brownish tinge. individuals may feed side by side where food is plentiful.
128 Adults are 8 to 10 inches long, including a 3- to 5- ( ) — Fox squirrels are found Sciurus niger Fox squirrel inch tail. Weights range from 1.5 to 3 ounces. The soft, mainly in the western and southern counties. Unlike velvety fur is grayish brown on the back and pearly white grays, fox squirrels prefer open, park-like woods with on the belly. The large, dark brown eyes are adapted for sparse ground cover, usually avoiding mountains and night vision. The so-called flying membrane is a loose extensive forests. Their nesting, denning and feeding flap of skin between the fore and hind legs on either side habits are much like those of gray squirrels. of the body; when a flying squirrel extends its legs, they Fox squirrels have gray to reddish-gray upper parts stretch the membrane taut, making an airfoil on which and buff to pale orange-brown undersides. Larger than the animal can glide from one tree to another or from a grays, weighing nearly two pounds, they are slower, more tree to the ground. A flying squirrel can sail up to 40 sluggish and less vocal. They are about 21 inches in yards in a downward direction. It uses its broad, flat tail length, including a 10-inch tail. as a rudder. Like the other Pennsylvania tree squirrels, fox squir- Flying squirrels are mainly arboreal, although they rels never actually hibernate in winter but will hole up also forage on the ground. They are rarely seen, since and sleep soundly through several days of snowstorms or they are nocturnal. They nest in hollow tree limbs and extreme cold. woodpecker cavities and sometimes in large Mating season is in January, and young birds' nests, which they cap with shred- are born in late February or early ded bark and leaves. After a gestation March. Average litter size is 2 to 4 period of about 40 days, 2 to 7 young young; only one litter is raised per (on average, 3 or 4) are born in year. April, May or June. The young are Fleas, chiggers and mosquitoes weaned after about two months. may bother squirrels, and tape- Adult males do not help the fe- worms have been found in some males rear the young. The south- specimens. Fox and gray squir- ern flying squirrel may produce rels seem to get along together two litters per year, with the sec- wherever their ranges overlap. ond litter arriving in September. Flying squirrels may be more ( Red Squirrel Tamiasciurus common than many people hudsonicus ) — The red squir- think. A good way to look for rel is alert, raucous and ener- them is to rap a stick against getic. About half the size of trees or branches that have cavi- the gray, the red measures ties; the squirrels may stick their about a foot from nose to tail- heads out or emerge to see tip and weighs about 5½ what's going on. ounces. In summer its fur is a Flying squirrels eat nuts; seeds; rich, rusty brown, turning grayer winter buds of hemlock, maple and in winter, when this squirrel also beech; tree blossoms and sap; fruits; develops prominent ear tufts. The un- berries; ferns; and fungi, both above-ground dersides are off-white. and subterranean types. They store surplus nuts in their The red squirrel is sometimes called a chickaree or a dens and also bury them in the ground. Although small pine squirrel, reflecting its preference for nesting in co- and apparently docile, flying squirrels are the most pre- nifers. Behavior, feeding habits and denning practices are daceous of the tree squirrels eating moths, beetles, in- generally similar to those of gray and fox squirrels, al- sect larvae, spiders, birds and their eggs, small mice and though reds sometimes nest in holes at the base of trees. shrews and carrion. Owls and house cats are major preda- They enjoy eating the immature, green cones of white tors of flying squirrels; foxes, coyotes, weasels, skunks, pine. Unlike fox and gray squirrels, reds do not bury nuts raccoons and black rat snakes also take them. The aver- singly, preferring a large cache — often in a hollow log age life span is estimated at five years. — for storing food. Active year-round, flying squirrels are quite sociable, The breeding season for red squirrels begins in late and in cold weather several individuals may share a tree winter, with 3 to 6 young born in April, May or June af- cavity, sleeping snuggled together for warmth; up to 50 ter a 40-day gestation period. Reds have strong territo- southern flying squirrels have been found in one nest. rial instincts, often defending food sources and den trees The southern flying squirrel may become torpid during against intrusion, and will even aggressively drive off the coldest part of the winter. One to three individuals trespassing grays. typically live on an acre of suitable wooded habitat. Glaucomys volans ( Southern Flying Squirrel ) — The ( Northern Flying Squirrel ) — The Glaucomys sabrinus southern flying squirrel is found throughout Pennsylva- northern flying squirrel is slightly darker and browner nia; it occurs from southern Maine to Florida and from than its southern counterpart. The two species' ecology Minnesota to Texas, with isolated populations in Mexico and habits are similar, although the northern flying squir- and Central America. The southern flying squirrel is rel shows a greater affinity for conifers, and the southern slightly smaller than the closely related northern flying flyng squirrel favors nut-producing hardwoods. The squirrel, and much more common in Pennsylvania.
129 squirrels in Pennsylvania today. They're our most heavily harvested small game species. Biologists estimate that a healthy autumn squirrel population is composed of about 35 per- cent juveniles, 30 percent sub-adults and 35 percent adults; also, that one gray squirrel per acre of woodland is a good density and that three per acre is excellent and only occurs on prime habitat. Although a hundred or more squirrels may thrive in a park or cam- pus, these situations do not occur in the wild. If food becomes scarce in the wild, large segments of the gray squirrel popu- lation may leave their home locales to travel in search of food and concentrate where they find it. Squirrel populations fluctuate. Good re- production — with most females bearing two litters — follows autumns in which large mast crops were produced. Severe winters, on the other hand, may reduce squirrel num- bers, especially if they follow a mast failure. Habitat Woodland areas can be managed to favor squir- rels. Of the two main forest types found in Pennsyl- vania — oak-hickory in the south and beech-birch- northern flying squirrel inhabits New England as far south maple in the north — the oak-hickory forest is better squir- as the mountains of northern Pennsylvania; there are also rel habitat, mainly because it has a greater variety of veg- disjunct populations in parts of the Appalachians to the etation types. south. Glaucomys sabrinus ranges from the Great Lakes Gray squirrels prefer a deciduous forest with a variety states west to Alaska. of tree species that provide a diverse food supply. A for- Northern flying squirrels inhabit old-growth and ma- est of mixed maples, oaks, hickories and beech, for in- ture forests, particularly northern hardwoods (beech, stance, would support more grays than would a ridge-top birch, maple) interspersed with hemlock, spruce and fir. stand of chestnut oaks. The fox squirrel needs woodland Home ranges are estimated at 5 to 19 acres and perhaps edge — places where the trees border corn or other crop larger. Adults do most of their foraging between dusk and fields. midnight, and for one to three hours before dawn. They A good squirrel woods should contain many mature feed heavily on lichens and fungi, including many under- mast-producing trees, a mixture of other tree and shrub ground ones, truffles and their relatives, which the squir- species to provide seasonal food variety, natural den trees rels sniff out. They also eat seeds, buds, fruits and insects. and hollow tree cavities for escape purposes. Diverse tree They den in tree cavities or woodpecker holes during the and shrub species ensure adequate food supplies even winter, and in the summer, they may build nests out of though weather, tree characteristics or tree vigor may leaves and shredded bark, in crotches of conifers high cause food crop failure of some types of vegetation. above the ground. Females produce one litter per year, Red, black and scarlet oaks regularly produce mast, usually with 2 to 4 young. while white and chestnut oaks are less reliable. Although The loss and fragmentation of old-growth forest may white oak makes better sawtimber, landowners favor the be causing a decline in the northern flying squirrel popu- red oak group if they wish to support a large, stable squir- lation in Pennsylvania, and it is considered a threatened rel population. In selective logging operations, four to species here. six hickories should be left per acre (if they are avail- able), as they are heavy mast producers. Population Old, hollow trees with many openings are rarely used for dens, although they provide temporary shelter from Once there were so many gray squirrels in Pennsylva- predators and hunters. A good den site is usually a tree nia that they were considered nuisances by pioneering nearing maturity with one or two openings into a cavity. farmers. In fact, bounties were paid on 640,000 squirrels Entrance holes are round and seldom over three inches in in 1749, and many more were doubtless taken for the diameter. If you want to manage a timber tract for squir- table. rels, keep at least four or five active den trees on each Settlement and development of our state has changed acre. In forests where trees have reached a mast-produc- the habitat, and squirrel numbers have decreased since ing stage but are not mature enough to serve as good den the 18th century — but even so, there is no shortage of sites, artificial nesting boxes may be used.
131 Wildlife Note — 23 LDR0603 Striped Skunk by Chuck Fergus The striped skunk ( Mephitis mephitis ) belongs to the They move at a deliberate walk, slow trot or clumsy gal- mustelid family, which includes weasels, ferrets, martens, lop; their top speed is about 10 miles per hour. They can fishers, mink, otters and badgers. Three other skunk spe- swim, but are poor climbers. Their senses of sight, smell cies live in the United States: hooded and hognose and hearing have been judged poor to fair compared with skunks, which inhabit the Southwest; and the spotted those of other wild mammals; their sense of touch, how- skunk, found over much of the country, but in the East, ever, is acute. north only to southwestern Pennsylvania. Skunks are armed with a potent defensive weapon: a The species commonly found in Pennsylvania is the pair of large scent glands found beneath the skin on ei- striped skunk. Widespread, it occurs in all 48 contigu- ther side of the rectum. These glands have nozzle-like ous states, southern Canada, and northern Mexico, from ducts, which protrude through the anus. Skunks discharge sea level to timberline in suitable habitat. The word their scent, or musk, through these nozzles, powering the "skunk" comes from the Algonquin Indian name for the stream with a strong hip muscle contraction. seganku animal, . Other names include polecat and the Musk is an oily liquid, creamy or yellowish in color. French Canadian , or "child of the devil." enfant du diable Its active ingredient is a sulphide called mercaptan. Field guides refer to the musk as "highly repellent to all mam- Biology mals." In short, it stinks. Musk can make a predator sick or, if the skunk has been able to direct the substance into Adult skunks are about two feet long, including a 7- the animal's eyes, temporarily blind. to 10-inch tail. They weigh 3 to 12 pounds, depending A skunk can shoot musk about twelve feet, but will on age, sex, physical condition and time of year. Males use it as only a last resort, preferring, instead, to bluff an on average are 15 percent larger and heavier than fe- enemy. If threatened, a skunk drums its forefeet on the males. ground, snarls, arches its back and raises its tail. It can Skunks have small heads, with small eyes and ears and spray in any direction by twisting its rump toward the a pointed nose; short legs; and wide rear ends. The bot- target. And, contrary to popular opinion, it can discharge toms of their feet are hairless, like those of bears or rac- when hoisted by the tail. coons. And, like these two other mammals, skunks walk Striped skunks are omnivorous. What they eat de- in a plantigrade manner — on the soles of their feet with pends on where they live and what's available. In sum- heels touching the ground. The claws of a skunk's fore- mer, they feed heavily on insects — adult and larval forms feet are long and sharp, well-adapted to digging. — including grasshoppers, crickets, beetles and wasps. A skunk is colored black and white. Its body is often (Pest insects eaten: potato bugs, tobacco worms and Japa- mostly black, with white occurring in a narrow blaze up nese beetles.) the middle of its forehead; a broad patch on the back of Skunks dig out bumblebee nests and scratch at the its head, and a V-shaped mark over its shoulders, which entrances of beehives, catching and eating any honey- forms stripes that continue along the animal's back, of- bees that fly out. Frequently they leave evidence of their ten uniting at the base of its tail. Stripes vary in length and width among individuals. The tail is bushy and black, usually tipped white. Sexes are colored and marked alike. A skunk's pelt is composed of soft, wavy un- derfur overlain with long, coarse guard hairs. Skunks molt yearly, beginning in April and ending some time in September. Skunks make a variety of sounds, includ- ing hisses, growls, squeals, soft cooings and churrings. By nature, skunks are placid and sluggish.
132 which lacks a well-developed sense of smell and appar- feeding: small, cone-shaped holes in the soil, pine needles, ently is not bothered by the skunk's musk, is a predator. leaf duff or suburban lawns mark where they've dug for Dogs, foxes, coyotes and bobcats take an occasional grubs. Other summer foods: spiders, toads, frogs, lizards, skunk, but the skunk's potent musk warns off most preda- snakes, mice, chipmunks and the eggs of turtles and tors. ground-nesting birds. Other mortality factors are diseases such as pneumo- In fall and winter, skunks eat fruit such as wild grapes nia, distemper, pulmonary aspergillosis, tularemia, bru- and cherries; small mammals such as moles, mice, voles cellosis and rabies; highway kills, starvation and trap- and shrews; plant items such as grasses, leaves and buds; ping. Skunks are host to fleas, lice, mites, ticks and vari- mast and carrion. Chiefly nocturnal, they hunt from dusk ous internal parasites. Most skunks live two to three years until dawn. in the wild; in captivity, they have lived 10 years. They den in ground burrows, beneath buildings, stumps, wood and rock piles and overhanging creek Population banks. Often a skunk will use an abandoned woodchuck burrow, although if none is available it will dig its own. The burrow has a central chamber (12 to 15 inches in Striped skunks live throughout Pennsylvania. High- diameter) about three feet underground, connected to est numbers are found in farming areas; lowest popula- the surface by one or more tunnels 5 to 15 feet long. The tions occur in densely forested mountain regions. Wild- central chamber is lined with dry grass and leaves. Skunks life researchers have estimated an average of one skunk per 10 acres of prime habitat and 13.5 skunks per square seem to prefer slopes for den sites, probably because these mile of agricultural land. areas drain well. In spring, summer and early fall, a skunk Mephitis mephitis has proven highly adaptable. Along may den in several different burrows; in winter, it tends with the woodchuck, raccoon, Canada goose, mourning to use just one. Normally solitary, males and females get together for dove, several species of blackbirds and other wildlife, breeding in February and March. Males fight with each the skunk prospers wherever humans clear land for farm- other, although they rarely discharge musk during these ing and remove or drive out larger predators. Skunks can live in an area for years and, because of conflicts. They travel widely in search of mates and breed their nocturnal habits, remain unseen — although per- with several females if possible. haps not "unsmelled" — by most people. Some farmers A mated female drives off males shortly after her 3- day estrus period ends. After 60 days' gestation, she bears welcome their presence, realizing that these small preda- tors eat many pest insects and rodents. 2 to 10 young (usually 5 to 7). Skunk are capable of breeding in their first year. Younger females may bear Skunks are susceptible to distemper and rabies. Trap- fewer young and give birth later in the year than older ping may help minimize the impacts of disease on a skunk population. Local populations are also affected by se- females. vere weather, food scarcities and habitat change. At birth, striped skunks weigh less than an ounce. Although they're blind and unfurred, the pattern of their Habitat future black-and-white pelage shows on their pinkish, wrinkled skin. They develop quickly. After three weeks, Skunks live in a variety of habitats. They favor mixed their scent glands become functional; at four weeks, their woods and brushland, rolling weedy fields, fencerows, eyes open; and at about two months the young are weaned wooded ravines and rocky outcrops in or near agricul- and ready to leave the den for nighttime hunting forays. tural areas. For day retreats (resting cover), they use By November, young of the year are as large as adults. hayfields, pastures, fencerows and brushy borders of wa- While family ties are usually broken in August or Sep- terways. Cornfields are good feeding areas, where skunks tember, some mothers over-winter with their offspring. forage for grasshoppers, grubs and beetles; high corn Community dens have been found containing 12 or more plants also protect young skunks from airborne and land skunks, mostly females and young. predators without impeding their movements. Skunks do not hibernate, although they may remain Although they may cover several miles each night dormant underground all winter. Their body tempera- while hunting, established individuals rarely wander more ture remains near normal. Several than a half-mile from their home burrows. In general, skunks may share the same winter den. adults range more widely than juveniles, males more Females usually lose 10 to 30 per- widely than females. cent of their body weight by spring; males lose only about 10 percent, as they are more inclined to leave their dens and Wildlife Notes are available from the feed during mild Pennsylvania Game Commission spells, mostly at Bureau of Information and Education night but occa- Dept. MS, 2001 Elmerton Avenue sionally during Harrisburg, PA 17110-9797 the day. www.pgc.state.pa.us The great horned owl, An Equal Opportunity Employer
133 Wildlife Note — 56 LDR0103 anagers anagers T T anagers T anagers anagers T T By Chuck Fergus Two tanager species migrate north from the Neotropics to breed in eastern North America. This is but a small percentage of the more than 200 Scarlet Tanager species in the tanager subfamily Thraupinae, many of whose members sport dazzling colors. The word tanager comes from a South American Indian word denoting a small, brightly colored bird. In tropical forests, mixed feeding flocks may include more than a dozen species, in plumages of red, yellow, green, blue and purple. of twigs. Sometimes they make short flights to catch fly- ing insects, particularly bees and wasps. They eat cater- ( Piranga olivacea ) — The bright- Scarlet Tanager pillars, moths, adult and larval beetles, dragonflies, est red I've ever seen met my vision when I focused bin- aphids, snails, spiders, worms and millipedes. During cold oculars on a male scarlet tanager singing in a treetop: snaps they land on the ground and hunt for beetles, earth- Against a backdrop of dark clouds and lit by the last rays worms and other terrestrial prey. They also eat tender of the evening sun, he looked positively fluorescent. buds, wild fruits and berries, and cultivated fruits such Males arrive on the breeding range (eastern North as cherries. America from southern Canada to the Carolinas) in late Scarlet tanagers nest in late May and June. To rear April and early May, just as trees are beginning to leaf a brood, a pair needs at least four wooded acres, with out. Their bodies are red, and their wings and tails are eight the optimum. During courtship the male flies to a jet black. Females, which show up a few days later, are a perch below the female; he droops his wings and spreads greenish yellow that blends with the leaves in which they his tail to show off his brilliant back. If the female strays rest and feed. Adults are about seven inches in length. outside his territory, he chases her back into it. Tanagers Scarlet tanagers favor dry, upland oak woods. They mate frequently, with the female crouching and calling also inhabit mixed and coniferous forests and shade to entice the male. She chooses the nest site and builds plantings in suburbs and parks. Males claim two- to six- the nest herself, over three to seven days, while the male acre territories by singing almost constantly from promi- sings from perches at the mid-forest level. Tanagers nest nent perches and driving away competing males. The lower than they forage; nests are 8 to 75 feet up (usually jeeyeet jeeay jeeeoo jeeyeer jeeyeet song sounds like , five often near the end of a horizontal branch 18 to 50 feet), to nine slightly hoarse notes ("like a robin with a sore in an oak, with a view of the ground and with clear fly- throat," said Roger Tory Peterson). Males whose territo- ways from nearby trees. The nest is flattish and rather ries adjoin sometimes perch along shared boundaries and flimsy, made of twigs and rootlets and lined with grasses countersing. Males return to previous years' territories, and stems; some nests are so loosely woven that the eggs but it's thought that females lack this strong homing in- can be seen from beneath. The female lays two to five stinct, so they rarely take the same mate in succeeding eggs, usually four; they are pale blue-green marked with years. brown. Insects and fruits form the bulk of the diet. Females The female incubates them for about two weeks, forage higher in the tree canopy than males. Both sexes with the male bringing food to her. Both parents feed work slowly and methodically, inspecting leaves, twigs insects and fruit to the young, which leave the nest after and branches and picking at leaf clusters near the ends
134 think. The highest populations occur in mature, exten- 9 to 15 days; their parents keep feeding them for two sive forests. Scarlet tanagers are absent from treeless ur- more weeks. Only one brood is produced each summer. ban areas and intensively farmed lands. Fledglings are brown, with slight streaking. In late summer the adults molt, and for a while the male is a Summer Tanager ) — This all-red Piranga rubra ( patchwork of red, yellow and green; he ends up looking tanager breeds mainly in the Southeastern U.S., where it like the female, but retains his black wings and tail. Scarlet is called the "summer redbird." Its range extends into tanagers leave Pennsylvania in September and early Oc- southwestern Pennsylvania, and it is regularly found only tober. volunteers found in Greene County. Breeding Bird Atlas They migrate mainly through the Caribbean low- it during the 1980s in Greene, Washington and Beaver lands of Middle America and spend most of the year east counties. Summer tanagers inhabit dry upland forests, of the Andes in remote forests of Colombia, Ecuador, with a preference for slightly open oak woods. In sum- Peru and Bolivia. There they sometimes join mixed-spe- mer they eat mainly insects: caterpillars, moths, beetles, cies flocks and feed in the canopy (along with other tana- cicadas, grasshoppers, flies and others; often they tear gers) and in fruiting trees. open wasp nests to feed on larvae, apparently without One scarlet tanager that had been being stung. The banded lived for ten years; most, however, summer tanager's probably don't survive for half that breeding and long. They're preyed on nesting habits are by hawks, falcons and similar to those of owls. Tanagers attack the scarlet tanager. squirrels and blue jays, Some Individuals which, nevertheless, seen in springtime in manage to rifle many Pennsylvania may have nests. Crows also eat eggs overshot their normal and fledglings. Brown- range and may then headed cowbirds parasitize turn around and more than half of all tanager move back south nests in some areas, particu- to find mates. larly where the forest has Summer tanagers been fragmented by spend most of the logging or home de- year on a large velopment. Scarlet range that extends tanagers nest state- from central wide in Pennsylvania Mexico to Bolivia and are more common and Brazil. than many people Summer Tanager Wildlife Notes are available from the Pennsylvania Game Commission Bureau of Information and Education Dept. MS, 2001 Elmerton Avenue Harrisburg, PA 17110-9797 www.pgc.state.pa.us An Equal Opportunity Employer
135 Wildlife Note — 61 Tundra Ldr1204 Swan By Chuck Fergus Have you hiked along a lake or river in early spring and seen flocks of white, long-necked swans resting or feeding in the shallows? Chances are good that those graceful, majestic swans feed by dabbling with their bills. They also tip their Cygnus birds were tundra swans. The tundra swan ( tails up, submerge their heads, and extend their necks to nip ), formerly known as the whistling swan, breeds columbianus off vegetation as deep as 3 feet below the surface. in northern Alaska and Canada and migrates south to winter Males and females form life-long pair bonds. On the breed- along and near the Pacific and Atlantic coasts. Tundra swans ing range, a pair maintains a territory in which they feed, fly across Pennsylvania in spring and fall, and some winter in nest and rear young. The territory usually includes part of a the southeastern part of the state. Our only other swan is the large body of water, used for feeding and escaping from preda- Cygnus olor ), originally imported from Europe mute swan ( tors. A typical territory covers an area of about half a square and now here in domestic and feral populations. mile. Young pairs may establish home areas a year or more before breeding. Each year, a pair will use the same territory, Biology defending it against other tundra swans and waterfowl in- The tundra swan — 4 to 5 feet long and with a wingspan cluding Canada geese, white-fronted geese, snow geese and of about 66 inches — is markedly smaller than the mute oldsquaws. When it encounters a competitor, a swan may swan. Adult tundra swans weigh 10 to over 18 pounds, with hiss, stare, raise its wings and, using the wrist portion of its males somewhat larger than females. The plumage is white, wings, deliver blows to the intruder. and the sexes look alike. The bill and the front portion of The male and the female build a nest out of grasses, the face are black (the mute swan has an orange bill with sedges, lichens and mosses, on the ground, usually on an black knobs at the base). Most adult tundra swans have a island or a low ridge or some other spot providing good yellow spot in front of the eye. The legs are black. The neck visibility. The mound-shaped nest is 1 to 2 feet across, with is held straight up most of the time (the mute swan, in con- a depression in the center. A pair may reuse the same nest in trast, usually keeps its neck in a curved position). successive years. Tundra swans court by facing each other, Whether taking off from water or land, before a tundra spreading and quivering their wings, and calling loudly. swan can become airborne it must take many running steps. Mating takes place in the water. The female lays three to Individuals can fly up to 50 miles per hour. The flight call five (rarely as many as seven) creamy white eggs. She broods consists of one to three syllables, usually described as varia- her clutch the majority of the time; the male broods only tions of the sounds oo , oh , and ; the voice of a tundra swan ou when she is absent. After 31 to 32 days, the eggs hatch. Pairs sounds similar to that of a Canada goose. Parents and young produce only one clutch per season; if the nest fails, the make softer kuk kuk sounds to communicate at close range. adults do not lay a second clutch. Tundra swans are good swimmers, propelling themselves Young swans, called cygnets, are light gray in color. Their with their webbed feet. They are able to dive beneath the eyes are open when they pip the shell. Their downy feathers water if necessary. dry out a few hours after hatching, and they begin walking As their name implies, tundra swans breed in the treeless about near the nest. Around 12 hours after the last egg hatches, tundra of northern Alaska and Canada's Northwest Territo- the parents lead the cygnets to water. With the young swim- ries, Nunavut, northeastern Manitoba, northern Ontario, and ming along behind, the adults use their feet to kick loose northwestern Quebec. The highest breeding concentrations and churn up plants on which the cygnets feed. For about a occur in the river deltas of Alaska and the Northwest Terri- week after hatching, the parents may brood the young. Tun- tories. Swans that breed east of Point Hope in northern Alaska dra swans sleep almost exclusively on land during the breed- winter on the Atlantic coast, while birds breeding from Point ing season; they stand or sit and may rest their head on their Hope south winter along the Pacific. back or tuck it partway under a wing. On their northern breeding range, tundra swans eat a va- On the breeding grounds arctic foxes, red foxes, bears, riety of plants, including sedges, pondweed, pendant grass, wolves, eagles, jaegers, gulls and ravens prey on eggs and arrowleaf, and algae, consuming seeds, stems, roots, tubers cygnets. Parents defend their eggs and young against smaller and some invertebrates. While floating on the water, tundra predators and usually flee their nest when a large predator,
136 the year. Flocks leave wintering areas in mid-March and such as a bear or a human, is several hundred yards away; this head north by stages. As much as 25 percent of the Eastern strategy may make the nest harder to find. Adults molt their population stops in the Susquehanna River Valley, where flight feathers during late summer. While molting, they can- they feed heavily and accumulate energy reserves for migra- not fly and, if threatened by a predator, will walk or run to a tion and breeding. They depart from the area in late March large pond or lake and swim out to the center. and move on to the next staging area in southern Ontario. Cygnets are able to fly after two to three months. As the They migrate through Wisconsin, Minnesota and North northern summer dwindles, family groups vacate their home Dakota in April, and arrive on the arctic breeding grounds territories and fly to staging areas, mainly along brackish by mid-May. Although family groups depart from wintering shores of river deltas, which remain free of ice longer than areas together, parent birds arrive unaccompanied by their other arctic wetlands. In late September, flocks begin head- young. ing south. Flocks are composed of multiple family groups Tundra swans are long-lived. The oldest known indi- and can number more than 100 individuals. The swans fly vidual was a banded bird that lived at least 21 years. Scien- in V-formations at altitudes of 1,800 to 4,500 feet and higher. tists estimate that 92 percent of adults, 81 percent of juve- Flocks follow traditional inland migratory routes. The nile males, and 52 percent of juvenile females survive each Eastern wintering population arrives in early October in the year. One study found a 52 percent survival rate for young Devils Lake area of North Dakota and the upper Mississippi eastern tundra swans during their first migration. River in Minnesota. Later, flying by day and night, they make a nonstop migration of almost a thousand miles to Habitat wintering areas in coastal New Jersey, the Susquehanna River During spring and fall migrations, tundra swans stop to Valley in southern Pennsylvania, the Chesapeake Bay re- rest and feed in estuaries, shallow ponds, lakes and marshes gion, and coastal North Carolina. Some birds winter in the fringing rivers. They also set down in harvested fields and Great Lakes region. Tundra swans arrive at the wintering those in which winter grains are growing. The Arctic breed- grounds from mid-November to mid-December. Banding ing habitat includes many lakes, ponds, pools and wetlands. studies indicate that individuals often return to the same Wildlife biologists believe that migratory staging areas wintering area year after year. are important late winter and early spring habitats in which Tundra swans winter on shallow tidal estuaries and on swans feed heavily and accumulate energy reserves for the freshwater lakes, ponds and rivers. In the past, tundra swans coming breeding season. In Pennsylvania, most tundra swans fed largely on submerged aquatic vegetation, as well as a winter along the lower Susquehanna River and at the Game small amount of animal matter, including clams. As aquatic Commission's Middle Creek Wildlife Management Area in plants have dwindled, due to the destruction of wetlands, Lancaster County. Many swans in the Eastern wintering popu- wintering swans have shifted to feeding on land. They for- lation stage in these areas. age mainly in farm fields, picking up waste corn and soy- beans left after the harvest, and eating crops such as winter Population wheat, rye, and barley. In winter, tundra swans spend the During the late 1800s, the tundra swan population was at night floating and sleeping on the water. During the full an ebb, probably because of unregulated shooting by mar- moon, flocks may feed at night. They fly back and forth ket hunters. Following the 1918 Migratory Bird Treaty, num- between resting and feeding areas. bers increased. was thought to have been Cygnus columbianus Individual birds tend to lose weight over winter. Studies extirpated from breeding areas in the southern Hudson Bay have shown that adult males region, but the species has recently begun nesting there again, may lose 14.5 percent along the coasts of Manitoba, Ontario and Quebec. Since and adult females 18.7 the late 1960s, as aquatic plants have declined and mute percent of their body swans (which compete for preferred habitats) have increased weight. When they fly north in number in the Chesapeake Bay, the number of tundra in the spring, they are at their swans wintering on the Chesapeake has fallen. A greater lowest body weight for percentage of the population now winters in North Caro- lina, where flocks feed extensively in agricultural fields. Since 1984, some states have allowed a limited hunting season on tundra swans. In the East, North Carolina, and Virginia issue permits for hunting swans. At this time, no swans may be legally hunted in Pennsylvania. The U.S. Fish and Wildlife Service, which monitors populations of migra- tory birds, has established target population sizes of 80,000 tundra swans in the East and 60,000 in the West. Today the population of Cygnus columbianus is considered stable. Wildlife Notes are available from the Pennsylvania Game Commission Dept. MS, 2001 Elmerton Avenue Harrisburg, PA 17110-9797 www.pgc.state.pa.us An Equal Opportunity Employer
137 Wildlife Note — 30 LDR0103 Vultures by Chuck Fergus Vultures, also called buzzards, are large, blackish birds have pink heads and necks; in young birds, these skin with broad wingspans, often seen soaring in wide circles areas are blackish. The turkey vulture's heavy bill has a in the sky. They are active in the daytime, when they sharp hook at the end for tearing. Its toes are equipped search for carrion to eat. Sometimes they perch in trees with strong, curved talons. or stand on the ground, usually near a dead animal. Al- Vultures are essentially voiceless; lacking a syrinx, or though graceful in flight, they are clumsy on the ground. voice box, all they can do is hiss and grunt. They have Seven species of vultures inhabit North America, in- keen vision and a sharp sense of smell, and use both to cluding the endangered California condor. Pennsylva- locate carrion. Their olfactory organs are large and well Cathartes aura ) nia has two species: the turkey vulture ( supplied with nerve endings. and the black vulture ( Coragyps atratus ). The Vultures are efficient turkey vulture is by far the more common; soarers, their long, it is found statewide, while the black vul- broad wings holding ture, more of a southern species, occa- them aloft like kites. sionally strays into southeastern Penn- In a rising current of sylvania. Both are protected by game air, a vulture can laws. maintain or even in- Black Vulture crease altitude without ( )— Turkey Vulture Cathartes aura flapping its wings. The turkey vulture is the chief avian Since they don't use scavenger of the United States, consum- their wings as much as ing huge quantities of unsanitary and (to hu- most birds, vultures man sensibilities) offensive carrion from have relatively small roads, fields and forests. Three subspecies in- breast muscles. Like habit North America: the eastern many hawks and falcons, (found in Pennsylvania); west- vultures migrate along ern; and Mexican turkey mountain ridges, using thermal vulture. updrafts to help keep airborne. Adults are about 30 They may remain on their roosts for inches in length, with several days when rainy weather wingspans up to six makes soaring difficult. feet. Their bodies are Observations from gliders show covered with black- that the turkey vulture has a ish-brown feathers, and lower sinking speed than the sexes are colored alike. black vulture. This heightened Turkey Vulture Seen from below, a turkey soaring ability may have helped vulture's wings appear two-toned, the flight feathers the turkey vulture extend its range farther north than lighter-colored than the rest of the feathering. Turkey the black, which keeps more to the south, where the vultures soar with wings held above the horizontal, form- warmer sun generates abundant strong thermals. ing a gently V. The birds rock and tilt on the air currents. Vultures eat all kinds of carrion, including fish, snakes, To probe deeply into carrion without becoming overly winter- and highway-killed mammals, domestic animals, messy, the head and neck are unfeathered — "like the and slaughterhouse refuse. Both captive and wild turkey bare arms of a butcher," wrote an early naturalist. Adults vultures have been observed killing smaller birds.
138 in the southeastern counties (Adams, Berks, Bucks, Favored breeding habitat includes remote areas inac- cessible to predators, such as caves, steep cliffs, hollow Chester, Cumberland, Delaware, Franklin, Lancaster, logs or stumps or dense thickets. (Unusual nesting sites: Lehigh, Montgomery, Northampton, Philadelphia and abandoned farm buildings; the snag of a dead tree with York), and occasionally in the southwestern counties (Fayette and Greene). Most turkey vultures winter in an entrance 14 feet above the nest; six feet below ground the southern United States, Central America and South level in a rotted stump; and a cavity in a beech tree 40 feet above the ground.) America. Vultures make little or no nest, depositing their eggs on the ground, in gravel on cliff ledges, or on rotted saw- ) — The black vul- Black Vulture Coragyps atratus ( dust or chips in logs and stumps. ture, about 24 inches in length, with a wingspan less than The female lays one to three eggs, typically two. Eggs five feet, is smaller than the turkey vulture. The black are 2¾ by 1¾ inches, elliptical or long-oval. Their shells has a short tail and black head. Because its wings form are smooth to slightly grainy, dull or creamy less sail area, it is not as efficient at soaring as the turkey white, overlain with irregular spots and vulture, and must fly using several rapid wing flaps fol- blotches of pale and bright brown. lowed by a short sail. Both parents share incubating. Airborne, the black vulture shows distinctive After 30 to 40 days, the eggs white patches on the undersides of the wings hatch into altricial young that near the tips. The black holds its wings more remain in the nest for about four horizontally than the turkey vulture. In weeks. The young birds eat car- both species, their naked heads look rion regurgitated to them by so small for the size of the bird that their parents. Careful conceal- from a distance they sometimes ap- ment or an inaccessible nest is pear almost headless. important at this time, as the The black vulture strays into, but carrion's stench may attract poten- is uncommon in, these southeastern tial predators. Pennsylvania counties: Adams, Vultures are gregarious; groups of Berks, Bucks, Chester, eight to 25 or more adults and juveniles Cumberland, Franklin, Lancaster, may wheel in the sky or roost together Perry and York. It has nested in in trees. Although turkey vultures like Adams and York counties. to nest in caves, they apparently rarely Behavior, food, and nesting enter them at other times of the year habits of the black vulture are and do not use them for winter shelter. similar to those of the turkey vul- Both young birds and adults molt once ture. Eggs, usually two per clutch, are Turkey Vulture each year, from late winter or early spring slightly larger than turkey vulture until early fall. eggs, and are grayish-green, bluish- The turkey vulture is a year-round resident of Penn- white, or dull white, with brown blotches and spots. In- sylvania. It is a common migrant in late February and cubation (by both sexes) takes 28 to 39 days. For un- March. In summer, it breeds throughout the state. In fall, known reasons, black vultures sometimes litter their nest it passes through during September and October, with areas with bright bits of trash, such as bottle caps and stragglers into early November. Cathartes aura winters broken glass. Wildlife Notes are available from the Pennsylvania Game Commission Bureau of Information and Education Dept. MS, 2001 Elmerton Avenue Harrisburg, PA 17110-9797 www.pgc.state.pa.us An Equal Opportunity Employer
139 Wildlife Note — 26 LDR0603 Weasels by Chuck Fergus Weasels are mammals belonging to the family concentrate on larger prey, relieving feeding competi- Mustelidae. The mustelids, which are characterized by tion when prey species are scarce. strong musk, vary in size, color, behavior and habitat. Secretive and wary, weasels are difficult to study in They are found worldwide, except for Antarctica and nature, and many gaps remain in our knowledge of their most oceanic islands. Other Pennsylvania mustelids are reproduction. Two of the species covered in this Wild- the striped skunk, mink, otter and fisher. Ferrets, bad- life Note (the ermine and the long-tailed weasel) exhibit gers and wolverines also belong to the family. delayed implantation, common in mustelids. In delayed Three weasel species occur in Pennsylvania: the er- implantation, mating takes place in summer or autumn; mine, also called the short-tailed weasel, Bonaparte's the fertilized eggs go through a short period of develop- weasel, and stoat; the long-tailed weasel, also known as ment and then lie dormant within the female until spring, the New York weasel; and the least weasel, or mouse wea- when they implant themselves in the uterine wall and sel. Ranges of the three species overlap in Pennsylvania, continue to grow. About 25 days later, young are born. the Great Lakes states and parts of Canada. In Delayed implantation has two possible adaptive Pennsylvania, the ermine is found mostly in advantages: It assures that all litters arrive at a the northern and eastern parts, the long- time when prey is abundant and competition for tailed is common throughout the state, and food is not extreme. Additionally, it doesn't re- the least is found in greatest numbers in the strict mating to one short period, increasing the southcentral and northwest. odds that females will come in contact with Weasels have long, slim bodies. Their males and be bred. Female weasels give birth to short legs have five small-clawed toes on 4 to 12 young, usually in underground nests. each foot. Their necks are long, their heads Least weasels are thought to produce several lit- small and triangular; eyes are small in rela- ters each year, while ermines and long-tailed tion to head size, and the ears, set low on weasels bear one litter in April or May. Young the skull, are rounded and well-furred. of all species are born blind and naked or Weasels travel with a loping gait, stopping sparsely furred. Adult males may bring food to occasionally to sit on their haunches or stand the mother and nursing young, which develop on their back legs to look around. rapidly and are on their own after weaning. Weasels are consummate predators. Their senses Weasels remain active year-round, seldom den- of sight, smell and hearing are acute, their hunting in- ning for long periods regardless of weather. During spring, stinct is keen, and they are active, aggressive and quick. summer and fall, their fur is brown with creamy or white They kill and consume a wide variety of prey, including underparts. In Pennsylvania, most or all ermines change animals larger than themselves. Small rodents form the from brown to white for winter, and perhaps one in six bulk of most weasels' diets. Although mainly nocturnal, long-tailed weasels turn white. Some least weasels un- weasels may hunt during the day. dergo the brown-to-white transformation, which is trig- They find prey mainly by scent, darting in and out of gered by shortening days. rodent burrows, checking brushpiles and rock crevices. A weasel pounces on its prey and bites it at the base of ( ) — The ermine is found in Ermine Mustela erminea the back of its skull; the weasel's forelegs hug the prey, northern regions around the world. In North America, it and the hind legs kick and scratch. occurs from Pennsylvania and Maryland north to New A weasel has a fast metabolism and must eat more food England, west across the Great Lakes states and Canada, in proportion to its body weight than other mammals of from western Montana south in the Rocky Mountains to similar size. Males are typically larger than females; some New Mexico, and from northern California north to biologists believe this size difference may lead males to Alaska. Although present throughout Pennsylvania (ex-
140 of the daytime in a den cept perhaps in the southwestern corner), the ermine is beneath a stone wall, much scarcer here than the closely related long-tailed rock pile, log, fallen tree, weasel. or abandoned building. Adults are 9 to 15 inches in length, including a 1.6- A den may have three or to 3.2-inch tail; males are larger and heavier than females. four tunnels leading to it. Weights are 1.6 to 3.7 ounces. Both sexes are smaller Breeding habits are than corresponding sexes of the long-tailed weasel; a large similar to those of the male ermine is about the same size as a small female long- long-tailed weasel. Fe- tailed. The ermine's bushy tail is shorter than that of the males — including long-tailed weasel. young of the year, 2 to 3 An ermine's pelt consists of soft, short underfur and months old — come into long, coarse, glossy guard hairs. The sexes are colored heat in summer. (Males alike, and immatures are similar to adults. Albinos are do not mature sexually rare. until late winter or early In summer, an ermine's upper-parts are dark brown, spring following the year slightly darker on the head and legs. The chin and throat Ermine they were born.) Young are are white, and the underparts are white or cream-col- born from mid-April to mid-May, ored, extending down the insides of the legs and includ- after a gestation period of about nine ing the feet. The end third of the brown tail is black. In months due to delayed implantation. winter an ermine is white, tinged with yellow on the un- The natal nest is underground, lined with leaves, derparts and back. The tail tip remains black. grasses, fur and feathers. The female bears 4 to 9 young, An ermine molts twice a year, in spring and autumn. usually 6 to 7. Newborns are blind, pink and weigh about The molts are triggered not by temperature but by half an ounce. amount of light per day, increasing in spring and decreas- Young develop rapidly. Their eyes open at 35 days; ing in fall. Molts usually begin on the belly and spread to they are lightly furred and play with each other inside the sides and back, finishing with the tail. Aside from and outside the den at 45 days. The male may help the the varying hare, the weasels are the only Pennsylvania female care for them. A 7-week-old male is larger than animals to turn white in winter. its mother. The autumn molt (brown to white) begins in October Ermines are preyed on by man, large hawks and owls, and is usually complete by late November or early De- foxes, snakes and domestic cats and dogs; they are para- cember. A molting ermine looks mixed brown and white. sitized by fleas and intestinal worms. Longevity is esti- The white-to-brown spring molt runs from mid-March mated at five or six years. to late April. An ermine's home range is thought to be about 30 to Like all weasels, ermines are alert, curious and bold. 40 acres, and 20 individuals have been found per square sound, hiss, purr, chat- took-took-took They make a rapid mile of good habitat. In winter and early spring, ermines ter, grunt and screech. When annoyed, they stamp their travel long distances for food, often 2 to 3 miles per night. feet or emit musk from their anal scent glands. In the northern part of its range, Mustela erminea lives Ermines can swim (sometimes pursuing prey in water) in low brush and thickets along waterways in heavily for- and climb trees, but spend most of their time on the ested areas. To the south, ermines inhabit open country ground. Their normal gait is a series of short bounds with fencerows and rockpiles, brushy land and, occasion- (about 20 inches), made with back arched. An ermine ally, swamps. can leap five or six feet and run about 8 mph for short distances. ) — The long- Mustela frenata ( Long-Tailed Weasel Prey includes mice, voles, rats, chipmunks, shrews, cot- tailed weasel is found from sea level to timberline from tontail rabbits, frogs, lizards, small snakes, birds, insects Maine across the United States and southern Canada, and earthworms, and carrion when hunting is poor. Cap- south to Florida, Mexico and South America, ex- tive ermines eat food equal to about one third of cluding the U.S. Southwest. Pennsylvania's larg- their weight every 24 hours. est weasel, it is fairly common statewide; dur- Ermines consume flesh, fur, feathers and ing years when Pennsylvania paid a bounty on bones of small prey, but generally just the flesh weasels, eight of every 10 turned in were long- of larger animals. They may lick warm blood tails. from a kill, but do not suck blood. They The long-tailed weasel is similar to the er- often kill more than they can im- mine in proportion, color and markings, al- mediately eat and cache excess though the long-tailed species is slightly larger kills. and its tail is longer. An ermine spends most Adult males are larger and heavier than fe- males. Length varies from 15 to 23.5 inches, in- cluding a 3.2- to 6.3-inch tail; weights are 2.5 to 9.3 ounces. Sexes are colored alike. In sum- mer, upper parts are a uniform dark brown, ex- tending onto the feet and toes (feet and toes Long-Tailed Weasel
141 ) — The least weasel is (Mustela nivalis Least Weasel of an ermine are white). The dark brown tail is tipped the world's smallest carnivore. It is found in Europe, north- black. ern Asia and North America. On our continent it inhab- The long-tailed weasel normally becomes white only its the Appalachian Mountains from Pennsylvania south in northern sections of its range; in Pennsylvania, five of to North Carolina, the northern Midwest, Canada and every six stay brown in winter, and farther south all indi- Alaska (it's absent in New England and the Pacific North- viduals probably remain brown. Mustela nivalis west). In Pennsylvania, is most common in Two molts occur each year. The fall molt is from Octo- the Allegheny Plateau area of our northwest and in the ber into November, the spring molt from mid-February southcentral part of the state. or early March into April. In autumn, molting starts on Least weasels are 6 to 8½ inches long, including a 1½- the belly and moves upward; in spring, the order is re- inch tail. They weigh 1 to 2 ounces. Males are slightly versed. larger and heavier than females. Coloration is brown Behavior of the long-tailed weasel is similar to that of above, white below. The chin and feet are white, and the the ermine. Long-tailed weasels are good swimmers and brown tail has no black tip. Sexes are colored alike. In adept climbers that will chase a squirrel up a tree. Al- Pennsylvania, some least weasels turn white in winter; in though generally solitary, two individuals may play to- Canada, most or all individuals change into white pel- gether. A long-tailed weasel is a persistent, efficient preda- age, including the tip of the tail. tor, chasing prey, pouncing on it, hugging it with the fore- Least weasels are just as aggressive and predatory as legs, and biting the victim at the base of the skull. the larger weasels and kill in the same manner. If disturbed Prey: small terrestrial mammals, bats, hares, rabbits, near its nest, an adult least weasel will chirp at its enemy. birds and their eggs, frogs, snakes, earthworms, insects and The chirp is a threat cry; least weasels also hiss (when carrion; smaller victims are eaten whole. A weasel can afraid or threatened) and trill (in friendly encounters with drag prey much heavier than itself. other least weasels). When agitated, they spray musk from A long-tailed weasel seldom digs a den, preferring to their anal scent glands. modify a chipmunk burrow, enlarge a hole under a stump, The species preys on mice, voles, small birds, insects, or move into a hollow log or a crevice in rocks, stone earthworms and small amphibians. Sometimes they kill walls, or beneath an abandoned building. Nests are lo- more than they can eat and cated about six inches underground and two feet from cache uneaten prey in their burrow entrances. Roughly nine inches in diameter, dens. Least weasels are noc- they are made of grass packed in layers and turnal, solitary and are sel- lined with shrew and mouse fur. dom seen; they spend most Breeding season is July and of their time hunting and August, and young are born consume food equaling 40 the following April or to 50 percent of their May after a 205- to Least body weight each day. 337-day gestation Least weasels breed and (average is 279 Weasel reproduce year-round, with days). Delayed im- the possible exception of plantation occurs, winter. Delayed implanta- with development tion does not occur, and two of the eggs resum- or more litters may be pro- ing during the last duced each year. A female's estrus 27 days of pregnancy. lasts four days. If bred, she bears 1 to 6 young (usu- One to 12 young may be born ally 4 to 5) following a 35-day gestation period. (average, 6 to 8). Young are blind and naked, but develop rapidly. Hair Newborns are about 2½ inches long and weigh 0.11 covers their bodies in four days; canine teeth erupt at 11 ounces. They are blind, naked and pink-skinned, and tend days; eyes open at 26 to 30 days; and weaning occurs be- to make more noise in the nest than young ermines. The tween 42 to 49 days, after which they are on their own. male brings food to mother and young. Young develop Immatures reach adult length after about eight weeks, and quickly. After 21 days, their backs are well-furred; at 28 adult weight when 12 to 15 weeks old. Females mature days, teeth erupt; at 36 days, their eyes open and the fe- sexually in four months, males in eight. male begins weaning them. Soon after, the young leave Least weasels inhabit meadows, fields, brushy land, or the nest and disperse, and by November are almost fully woods. They may take over nests and burrows of mice, grown. moles and voles, lining them with fine grass or fur; in win- Females breed in their first autumn, while males do ter, the fur lining may be an inch thick and matted like not mature sexually until the following year. Man, foxes, felt. Least weasels rarely travel more than 100 yards from dogs, hawks and owls prey on long-tailed weasels; cap- their home burrows, and the average individual range is tive specimens have lived five years, but wild individuals estimated at two acres. lives Mustela frenata probably do not survive that long. This tiny weasel occupies a lower position in the food in open woodlands and brushy fields, preferably near wa- chain than ermines and long-tailed weasels. It is preyed ter. Rocky fencerows are favorite hunting grounds. Size on by the larger weasels, snakes, owls and cats. Longevity of an individual's range would vary with food availability in the wild is not known. and type and quality of cover.
143 Wildlife Note — 28 White-Tailed Deer by Chuck Fergus The white-tailed deer, Odocoileus virginianus , was so onset of the breeding sea- named because the underside of its tail is covered with son than they do at its conclu- white hair, and when it runs it often holds its tail erect so sion. Hence, a 140-pound buck in December might have that the white undersurface is visible. Whitetails belong weighed 180 pounds in September. to the Cervidae family, which in North America includes Hair color is alike in both sexes. In adults, the belly, elk, moose, caribou and mule deer. Cervids are split- throat, areas around the eyes, insides of the ears and the hoofed mammals with no incisor teeth in the front of the underside of the tail are white all year long. During sum- upper jaw. They are classed as ruminant animals, mean- mer, the upper parts of the body are reddish brown, and ing they have a four-chambered stomach and frequently in winter they are grayish brown. chew a "cud." Adult male whitetails grow and shed a set Summer hairs are short, thin, straight and wiry. Win- of antlers each year. On rare occasions, adult females also ter hairs are long, thick, hollow and slightly crinkled. grow antlers. Winter hairs afford the deer excellent protection against Scientists have identified 30 subspecies of whitetails the cold. Summer coats are shed in August and Septem- in Central and North America. Whitetails occur from ber, winter coats in May and June. southern Canada south through the United States and Melanistic and albino deer occur but they are rare. Mexico to Panama, but they are absent from most of Partial albinos, sometimes called "piebalds" or "calico" Canada, Nevada and Utah. They occur commonly deer, occur more frequently. throughout Pennsylvania. Fawns are born with white spots in the upper coat. The largest of the subspecies is the northern wood- When a fawn is lying on the ground or in dry leaves this land whitetail, and the smallest is the endangered Florida coat looks like the sun hitting the ground after it passes Key deer. The subspecies throughout most of Pennsylva- through the treetops. This provides excellent camouflage nia is the northern woodland whitetail. for the fawns. Their summer coats are molted about the In Pennsylvania the average adult buck weighs about same time as the fall molt in adults, and fawns take on 140 pounds live weight and stands 32 to 34 inches at the the same coat colors as adults in the fall. shoulder. He is about 70 inches long from the tip of his Whitetails have scent-producing glands: two tarsals, nose to the base of his tail. His tail vertebrae add only one inside each hind leg at the hock joint; two metatar- about 11 inches, but the long sals, one on the outside of each hind leg between the hair makes it far more con- hock and the foot; four interdigitals, one between the spicuous. Does tend to aver- toes of each foot; and two preorbitals, one below inside age less in weight and body corners of each eye. The tarsals and metatarsals release length than males of the scents conveying excitement or fear, while the same age from the same area. interdigitals produce odors which let deer trail each other Deer weights vary consid- by smell. The preorbitals are used to personalize the erably, depending upon age, prominent overhanging branch at "scrapes" — thrown- sex, diet and the time of year. For up dirt patterns — used to attract does during the rut. example, breeding-age bucks may Deer can run at 40 miles per hour for short bursts and weigh 25 to 30 percent more at the maintain speeds of 25 miles per hour for longer periods.
144 While antlers grow they're soft and subject to injury. They are also good jumpers capable of clearing obstacles Bent and twisted tines and main beams are a result of up to nine feet high or 25 feet wide. The air-filled hairs injury to the antler while it was growing. Broken antlers of their coats enable them to swim easily. occur after the antler has stopped growing and is hard. Although whitetails are color-blind and sometimes The small cavities sometimes seen in polished antlers are have a hard time identifying stationary objects, they are a result of botfly larvae damage during the growing pe- easily alerted by movement. Their keen senses of smell riod. and hearing also help them detect danger. The antler cycle is influenced by secretions from the Usually deer are silent, but they can bleat, grunt, pituitary gland. Changes in length of daylight periods whine, and when alarmed or suspicious, make loud and, to a lesser degree, temperature influence the hor- "whiew" sounds by forcefully blowing air through their mone secretions from this gland. Hormones are believed nostrils. Does whine to call their fawns and fawns bleat to be a factor in the initiation of new antler growth. In- to call their mothers. creases in the amount of testosterone in the blood of Although antler growth is evident on male fawns, the whitetail bucks in late August and early September cause button-like protrusions are not prominent. A buck's first blood flow to the antlers to stop. The velvet dies and is set of antlers begins to grow when it's about 10 months shed or rubbed off. Throughout the breeding season, tes- old. Each year after the buck reaches this age, it will grow tosterone levels continue to increase until they peak in and shed a new set of antlers. Typical antlers curve up- November, usually coinciding with the height of breed- ward and outward to point forward, and consist of two ing. After that, testosterone abates, apparently trigger- main beams with individual tines growing upward from ing antler shedding. them. Shedding usually occurs earlier in northern states than If the yearling buck comes from an area with poor food southern ones. Spike bucks tend to retain their velvet conditions, his first set of antlers may be only "spikes" — longer and shed their antlers sooner than bucks with antlers consisting of single main beams only. Spikes are branched antlers. The roles of age and nutrition in the more common in yearling deer than older ones because length of antler retention are not fully understood at antler growth starts at a time when the young buck's body present. is still growing rapidly. But because antler development is tied in closely with the animal's nutritional status, older Social Organizaton bucks might also carry spikes if they come from an area with poor food conditions. More of the nutriments in the The social organization of the whitetail is largely ma- young buck's body are going for body growth than in older triarchal. Although large numbers of deer are sometimes bucks, hence, less are available for antler development. seen together in feeding areas or wintering areas, these Fifty percent or more of the yearling bucks from poor associations are usually temporary and do not reflect the deer range in Pennsylvania may produce only spikes, same strong ties as family associations between related compared to 10 percent or less from good deer range. does. The most common social group is an adult doe, her Antlers generally begin to grow in March or April. fawns and her yearling female offspring. Sometimes three Growing antlers are covered by a skin called "velvet." or four generations of related does are present in a fam- This velvet is covered with soft hairs and contains blood ily group. When fawning season rolls around in late May, vessels which supply nutriments to the growing antlers. adult does leave the family group and remain alone to The solid bone-like substance which makes up the pol- bear and rear their fawns. Once a pregnant doe leaves ished antler is secreted by cells on the inside of the vel- the family circle to bear her fawns, her yearling offspring vet. By August or early September antler growth ceases are left on their own for the summer. and the velvet is shed or rubbed off by the buck as he Siblings tend to remain together throughout most of rubs saplings, shrubs or rocks with his antlers. Polished summer. Sibling groups with yearling bucks separate in antlers are carried throughout most of the breeding sea- September as the rut approaches. Yearling bucks tend to son, which can last into late February. The antlers are disperse from the mother's home range at this time. Year- shed at the end of ling does remain in the mother's home range and gener- this period, and a ally rejoin their mother and her new fawns between Sep- new set begins to tember and October. grow in March or During the breeding season adult and yearling bucks April. tend to stay alone except when in pursuit of a female approaching estrus. After the breeding season, in late January, yearling and adult bucks form loose associations of small groups, usually two to four animals, which re- main together throughout most of the winter and sum- mer months. These groups break up around September when the rut starts. Reproduction The mating season of white-tailed deer begins as early as September and can last into late January. Breeding
145 gram to shelter deer in severe winter weather is some- activity reaches its peak in early November, and most adult times necessary where suitable cover of that type is ab- females have been bred by the end of December. Some sent. The value of these plantations to deer is low during females are capable of reproducing at seven or eight most of the year but high during winter. As with months of age and give birth at 14 or 15 months of age. clearcutting, conifer plantations should be kept small and Most of these animals breed a month or two later than scattered. Large plantations are unnecessary. Small clumps older does, and they usually produce a single fawn. of only 30 to 60 trees will suffice. Individual trees within The age and health of a doe influence her reproduc- the plantation can be spaced as far apart as eight to ten tive capacity. Females from the best range produce more feet. Preferably, these clump plantings should be located fawns than those from poor range. Adult females (2.5 years in lowlands or on south-facing slopes. and older) usually produce twins, and triplets are not un- common. There is a tendency for young females to pro- duce a larger percentage of male offspring than older does. Management Food Habits Deer are a valuable natural resource, but they must be closely managed or they'll quickly overpopulate the range they inhabit. When overpopulation occurs, deer strip their Whitetails eat a wide variety of herbaceous and woody habitat of its life-supporting qualities, not just for deer, plants. In a Pennsylvania study where biologists exam- but for many woodland wildlife species. Crop and other ined and measured the food contained in the rumens of property damage problems also increase, as well as deer- vehicle-killed deer, about 100 different plant species were vehicle collisions. identified. More than half were tree, shrub or vine spe- Pole timber and over-browsed woodland cannot sup- cies, the remainder, herbaceous plants. A good number port large densities of deer. Without adequate food of ingested plants could not be identified. sources and cover, deer populations are stressed. Deer Whitetail food preferences are largely dependent on must work harder for daily nourishment and often have plant species occurring in an area and the time of year. not built up the energy reserves they need to make it Green leaves, herbaceous plants and new growth on woody through winter. Young deer, because they require food for plants are eaten in the spring and summer. In late sum- both growth and energy reserves, are most susceptible to mer, fall and early winter, both hard and soft fruits such as winter starvation and exposure. They simply don't have apples, pears and acorns are a major component of their the muscle to push away older, more dominant deer at diet. In winter, evergreen leaves, hard browse and dry feeding locations. leaves are eaten. Good supplies of a variety of natural Under-nourished deer are more prone to succumb to foods at all times of the year are essential if an area is to exposure and disease. In addition, unhealthy deer typi- carry a healthy deer population. cally have smaller body size, lower reproductive rates and smaller antlers. So the key to managing deer is keeping Habitat their populations at healthy levels. This essentially en- tails ensuring they don't exceed their range's ability to A seedling-sapling forest satisfies two deer needs: (1) concealment, and (2) food in the form of buds, stems and support them. We use hunting to adjust deer populations. leaves of shrubs and young trees. Seedling-sapling stands Population control can be accomplished only through a rationed harvest of female deer. The Game Commis- are created most frequently by timber harvesting. sion issues permits entitling hunters to take antlerless deer Clearcutting, or even-aged timber management, means cutting most trees larger than saplings, but leaving an area in particular management units, areas where the agency continually collects deer population data. Deer popula- of land looking "clear." This cutting technique should be tions and density restricted to areas where sufficient regeneration is present goals based upon to guarantee a sustainable forest. In the timber cut, snags, habitat, along den trees, mast trees and rare tree species should be left behind to assure a good habitat diversity for an abun- with hunter suc- dance of wildlife. cess rates, are Newly cut treetops provide an immediate source of used to gauge how browse in winter months when snow cover makes other many hunting per- mits should be is- sources of food unavailable. Therefore, when possible, the sued. actual cutting operations should be carried out when the Public support trees are dormant. However, the greatest benefit of of our manage- clearcutting to deer lies in the often abundant new growth ment program is vegetation and succulent sprouts and seedlings that flour- essential to main- ish in the sunlight following the cutting. Once established, taining the deer this new thick growth also provides concealment for deer, population as a not only in the early years following the cutting, but for a public asset to be longer period, after much of the browse has grown out of enjoyed by future their reach. generations of Penn- While most deer habitat management should revolve around a forest cutting program, including the establish- sylvanians and visitors ment of herbaceous openings, a conifer tree planting pro- to Pennsylvania.
147 Wildlife Note — 17 LDR0103 Wild Turkey by Chuck Fergus The wild turkey is a shy, permanent resident of domesticated the big birds. Later, the wild turkey became Pennsylvania's woods and mountains. Infiltrating a flock a steady food source for white settlers. It earned a sym- of these big birds is no easy feat, and when the hunter or bolic role as the main course of the Thanksgiving meal, naturalist is finally discovered, he's treated to a spec- which epitomized the successful harvest. Benjamin tacle as the flock breaks up. Turkeys flap upward on loud Franklin so admired the big bronze bird that he wanted wings. Some run full tilt, heads extended on serpentine it for our national emblem. Comparing it to the bald necks. Others sneak along through the understory. eagle, he said: "The turkey is a much more respectable Eventually, quiet returns to the woods. And, with time bird, and withal a true original Native of America." the first tentative calls of regrouping birds break the si- Several theories explain how the bird got its name. lence . . . . Early naturalists may have confused it with a species of Turkeys have long been important to man in North Old World guinea fowl found in Turkey. Or the word may America. Indians hunted them for food, and some even describe one of the bird's calls, which sounds a bit like "turk, turk, turk." Still a third explanation is that the word sprang from an American Indian name for the bird. "firkee." By whatever name, the fact remains that this big bird was nearly exterminated by the ax, the plow and the gun. As our nation grew, settlers cleared forests for farms. And they shot turkeys for food. By 1800, market hunters were selling the birds for as little as six cents each. By the early 1900s — when eastern forests had been lum- bered and periodic fires hampered their regeneration — the turkey was in trouble. Fortunately, here in Pennsylvania, the newly-formed Game Commission stepped in. Through seasons and bag limits, the agency succeeded in safeguarding what remained of the state's once-thriving popu- lation. It was found in the mountains of the state's southcentral counties. Over time, the agency experimented with ways to return turkeys to the rest of Penn's Woods. A tur- key farm was tried. So was placing hen tur- keys in holding pens for wild gobblers to breed with. But neither technique faired well. What turkeys needed was habitat improve-
148 ments. In the 1950s, as the state's forests began to ma- warms up, they eat more insects, including grasshoppers, ture, turkeys began to expand their range. Expansion was walking-sticks, beetles, weevils, dragonflies and larvae. furthered through a Game Commission wild turkey trap- They also consume spiders, harvestmen, ticks, millipedes, and-transfer program that would become a model for ev- centipedes, snails and slugs. But even in summer, a ma- ery state interested in turkey restoration. Today, turkeys jority of the diet (perhaps 90 percent) is vegetable. A are found in every county, and this wily bird has devel- wide variety of plant species are eaten, as well as a num- ber of plant parts, including fruits, seeds, seedheads, tu- oped quite a following among hunters. bers, roots, bulbs, stems, leaves, flowers and buds. In fall, turkeys eat mast (beechnuts, acorns); fruits Biology (dogwood, grape, cherry, gum, thornapple); and seeds (grasses and sedges, ash, corn, oats, weeds). During win- North American turkeys — including the domesti- ter, they rely on seeds, nuts, and fruits left over from au- cated bird — belong to the single and highly variable tumn, and on green plants, crustaceans and insect larvae . Taxonomists recognize at least species Meleagris gallopovo found in and around spring seeps. Temperature of this five subspecies; the variety found in Pennsylvania is water is above freezing, so the seeps remain open all win- known as the Eastern wild turkey. Turkeys are gallina- ter, providing food for turkeys and other wildlife. ceous — "chicken-like" — birds (order Gal- A turkey often scratches for its food, kicking liformes), related to grouse, quail, pheas- forest duff and leaves behind. If the bird ants and chickens. finds an acorn, it picks up the nut in its Adult males, also called "gob- beak, straightens its neck, and swallows. blers" or "toms," stand 2½ to 3 The nut is stored in the bird's crop, a feet tall and 3 to 4 feet long. flexible bag in which juices and body Females (hens) are shorter by heat work to soften it. Then the nut about a third and weigh about passes into the gizzard, an enlarged, half as much. Gobblers weigh thick-walled section of the food up to 25 pounds, averaging canal which contains small stones 16. Adult hens weigh 9 to 10 and gravel called grit. Strong pounds, and six-month-old birds, 6 muscles use the grit to grind down to 13 pounds. the acorn. The wild turkey looks much like the Turkeys may range up to several domesticated subspecies, except the wild miles a day in search of food and wa- bird is slimmer, has a smaller head, a longer ter, sometimes establishing regular neck, longer, rangier legs, and smaller fleshy feeding areas if left undisturbed. In head and neck adornments. Tail feathers and autumn, hunters "read" the food tail coverts are tipped chestnut brown on scratchings to determine when a wild birds, white on domesticated ones. flock passed by, what size the Plumage is an overall rich brown. In shad- flock was, and which way the ows, turkeys appear black; in bright sunlight, birds were headed. their feathers gleam with copper, blue, green and Physical properties, behav- mahogany highlights. A hen's plumage is duller ior: Like most birds, turkeys and not quite as iridescent, and her breast feath- have keen eyesight and hearing. ers end in a brown or buff band, while those of a They hide cleverly, fly 40 to 55 mph, gobbler are tipped with black. cover more than a mile while airborne, swim with ease — Gobblers have spurs — sharp, bony spikes on the but they usually rely on their feet to escape danger. The backs of their legs that are used in fighting — and rough, strides of chased gobblers have been measured at four black "beards," growths of rudimentary, hair-like feath- feet and their top speed estimated at 18 mph. Tracks vary ers called mesofiloplumes, which protrude from their somewhat by the age of the bird (a young tom, for ex- breasts. These beards grow quickly for the first four or ample, might have a shorter print than an adult hen) but five years, then more slowly, until they're about 12 inches any track larger than 4¼ inches, from the back of the long. The ends may break off, though, so beard length heel pad to the tip of middle toe, was probably made by isn't a reliable indicator of age. Usually, hens have nei- a male. ther spurs nor beards. Each evening, turkeys fly into trees to spend the night. A gobbler's head is practically bare, while that of a A flock of up to 40 or more birds may roost in the same hen is covered with hair and fine feathers. A fleshy, pen- tree or in adjacent trees. They prefer the shelter of coni- cil-like appendage called a caruncle, or snood, dangles fers during inclement weather. In early morning, the birds from between the gobbler's eyes. Heads of both sexes are glide to the ground, call, and regroup for feeding. bluish-gray, and their necks may have a pinkish flush. Turkeys make a wide range of sounds. Best known is During mating season, a gobbler's head and neck are more ), used ill-obble-obble-obble the male's gobble (described red; during courtship display, his snood may become long in spring to attract females and proclaim territory. Other and swollen, and the color of his head and neck changes keouk, keouk, keouk calls include yelps ( ), made by both quickly from red to blue, purple and white. sexes; the cluck ( kut ), an assembly note; the whistle, or Food: In spring, turkeys eat tender greens, shoots, tu- "kee-kee run" of a young bird ( kee, kee, kee ); and the bers, left-over nuts and early insects. As the weather
149 tumn they're practically self-sufficient. Birds of the year putt alarm note ( ). Gregarious birds, turkeys call when sepa- can be identified by their middle tail feathers, which are rated from the flock. By imitating such calls, hunters at- longer than the others. In adults, the edge of the fanned tract birds. tail forms an unbroken curved line. Reproduction: Toward the end of March, a male tur- In autumn, flocks often contain several old hens and key changes physically. His fleshy crown swells and turns their young, and occasionally hens that have not raised pale, his wattles redden and hang from his head, and he broods, for a total of 40 or more birds. Old toms usually develops a thick, spongy breast layer containing oils and remain apart, in pairs or trios. During early winter, family fats to help sustain him over breeding season. Toms gobble groups disperse and form new flocks by sex and age: hens, loudly in early morning and sometimes in late evening. young toms and old toms. Blowing a car horn, beating a tin pan, or making almost Although susceptible to diseases turkeys are hardy any loud noises may provoke lusty gobbles. animals. Disease outbreaks have been verified in the past, If hens are present, a gobbler will display by fanning but none has had substantial population impacts over his tail, erecting his feathers, and tucking his head back large areas. Periodically, a harsh winter may lead to star- against his body. He will strut back and forth, hissing and vation, especially if there is deep, powdery snow which dragging his wing tips on the ground. Rival males fight: makes it difficult for birds to become airborne. each grasps the other's head or neck in his bill and tries to shove or pull his foe off balance. The first bird to let go or Population lose balance gets thrashed with wing and spur. Year-old birds are sexually mature; hens often mate In 1900, few turkeys were left in the eastern United during their first spring, but young males usually can't States, largely because widespread logging had destroyed compete with mature gobblers. A dominant male may their woodland habitat. An estimated 5,000 birds re- collect a harem of 8 to 12 or even more hens. Males are mained in Pennsylvania, a far cry from the large, healthy polygamous: a gobbler mates with several hens and plays population that had existed here (mainly in southcentral no part in nest site choice, brooding eggs or rearing young. Pennsylvania's oak and American chestnut forests) a cen- In late April, mated females slip away from the flock. tury earlier. They choose nesting spots in wooded or brushy areas, near water sources and usually close to forest clearings or old Restoration of the species involved several steps. First, fields. Nest: a leaf-lined depression in the ground. It may refuges were established and new game laws strictly en- forced to protect remaining local populations. Half-wild be located under the curve of a fallen log, concealed by turkeys were bred on the Game Commission's wild tur- vegetation or fallen branches or at the base of a tree. key farm, beginning in 1930. These birds proved to be The gobbler's sperm is stored in the hen's oviduct, so nearly useless. As cut-over forests began to regrow, exist- that fertilized eggs may be laid up to four weeks after mating. One mating is usually sufficient to fertilize an ing wild flocks began to move into new areas on their own. In addition, wild birds were trapped in areas where entire clutch. A hen lays an egg nearly every day until her nest contains 8 to 15 (average, 12; smaller clutches they were abundant and transferred to suitable, but un- by younger birds), but won't begin incubating constantly occupied, habitat to speed up the dispersal that was natu- rally occurring. The superiority of this approach over until after all eggs are laid. game farm turkey releases has been obvious. Today tur- Eggs are oval and pointed markedly at one end. The smooth, dull shells are colored pale buff and are evenly keys are found throughout the state and are abundant in marked with reddish-brown spots or fine dots. Foxes, bob- areas where, in the past, continual releases of game farm cats and great horned owls prey on nesting hens; eggs are turkeys failed to establish even limited self-sustaining eaten by the aforementioned predators plus mink, rac- populations. coons, opossums, black snakes, skunks, crows and red The Game Commission also works to improve turkey habitat, especially brood and winter range, which are nec- squirrels. Incubation takes about 28 days. After young hatch, essary for population expansion to occur. Penn's Woods is currently home to about 250,000 wild turkeys. the hen broods them until they're dry and then, if the weather is mild, leads them away from the nest. What are a turkey's chances of survival, from egg to adult? The following statistics are from Poults: Young turkeys are called poults. They're cov- The Wild Turkey - , edited by James G. Dickson and ered with a fine, brownish fuzz and even at hatching have Biology and Management published in l992 by Stackpole Books: (a) nesting suc- a wild turkey's distinctive long neck and legs. Easy game for predators, their main defense is to hide. They scatter cess of the turkey is 31 to 45 percent, about normal for a ground-nesting species; (b) 53 to 76 percent of poults and freeze at the hen's warning call, remaining motion- perish, mostly within two weeks of hatching; (c) life ex- less until she sounds the all-clear. A hen may feign injury to lure intruders away from her young. pectancy of a turkey surviving its first two weeks of life is Poults need high-protein food, and the hen soon leads still less than 1½ years, although a few have been known them to open areas where insects abounds. Poults eat leaf- to survive more than 10 years in the wild; (d) annual tur- hoppers, crickets, other insects and larvae, tender greens key survival generally ranges from 54 to 62 percent; (e) predation is generally the most common cause of wild tur- and fruits. The hen broods them nightly for at least two weeks, until their wings develop and they can roost in key mortality; and (f) hunting-related turkey mortality is trees. When poults are about three weeks old, several fam- highly variable, depending largely on varying hunting ily groups may merge to form a flock of hens and poults. season regulations, but can range from less than five per- cent to more than 50 percent of all losses. Six-week-old poults are fairly strong fliers, and by au-
150 grasses and forbs to spring up; increased plant life gives Habitat rise to increased insect life, and insects form a key part of a young turkey's diet. Thus, forest openings resulting from Turkeys have shown more tolerance for fragmented cleared timberlands, old logging roads and logging camp habitat (woodlots) and human disturbance than previ- sites, power line rights-of-way and old beaver meadows ously believed, but they still depend on forested habitats should be preserved, or planted with a grass-legume mix- and do best with limited human activity. Habitat diver- ture if needed. Spring seeps are also important, as they sity — varying habitat types and differing ages — is the provide insect and vegetable food over winter. key to good turkey habitat. Turkeys seem to do best with Free water (streams, lakes, ponds, springs, seeps, rain- a mix of forested, actively farmed and reverting farmland water in shallow depressions) has never been demon- habitat types. strated to be lacking for wild turkeys in the eastern United A turkey flock uses an extensive area — several thou- States. Artificial feeding? Turkeys don't generally need sand acres — during a year to meet its needs, so small it, especially if they live in good habitat. Such feeding landowners shouldn't expect to have resident flocks. How- may actually pose a hazard by unnaturally concentrating ever, anyone with forested land can do something to ben- a local population, thus increasing the danger of poach- efit turkeys, especially if neighboring landowners will ing and disease spread, and giving predators an unnatural cooperate. advantage. Trees such as oaks, beech, cherries, etc., are most ben- Every day, expanding towns and new roads cut into eficial to turkeys when producing the maximum mast; this our state's limited amount of wildlife habitat. Second occurs when trees are 50 to 100 years old. Landowners home development — booming in the northcentral's can manage their woodlands for saw-timber by conven- prime turkey range — is especially threatening. We can- tional even- or uneven-age silvicultural approaches and not expect to continue taking land at this rate and still "pushing" young hardwood stands to maturity by culling have animals like turkeys and bears which don't coexist out less-vigorous and non-mast-producing trees. Some well with man. Snowmobiles, trailbikes and four-wheel- woodland cuttings — which aren't economical in terms drives disturb turkeys, even though the drivers of these of timber management — can be made to allow more sun- vehicles may never see a single bird; if such intrusion goes light to reach grape, dogwood, greenbrier, hawthorn, on too long, it can cause flocks to leave a given area for viburnum and other food-producing understory species. good. Planting shrubs such as Japanese barberry, autumn olive, Pennsylvanians can be proud of the wild turkey's res- Asiatic crabapple and Washington hawthorne will pro- toration to this state. With enough concern for meeting vide abundant and persistent winter foods. the birds' needs, we can enjoy them well into the fu- all Forest clearings are especially used by hens and poults. ture. Here, sunlight penetrates the tree canopy and allows Wildlife Notes are available from the Pennsylvania Game Commission Bureau of Information and Education Dept. MS, 2001 Elmerton Avenue Harrisburg, PA 17110-9797 www.pgc.state.pa.us An Equal Opportunity Employer
151 Pennsylvania Game Commission Wildlife Notes Envirothon students will be able to identify the animals described in the Wildlife Notes listed below. 1. Bats 27. Mink & Muskrats 2. Beaver 28. Northern Cardinal, Grosbeaks, Indigo Bunting, and Dickcissel 3. Black Bear 29. Opossum 4. Blackbirds, Orioles, Cowbird, and Starling 30. Owls 5. Blue Jay 31. Pheasants 6. Bobcat 32. Porcupine 7. Canada Goose 33. Puddle Ducks 8. Chickadees, Nuthatches, Titmouse, and 34. Raccoon Brown Creeper 35. Raptors 9. Chimney Swift, Purple Martin, and 36. River Otter Swallows 37. Ruffed Grouse 10. Common Nighthawk and Whip-Poor-Will 38. Shrews 11. Cottontail Rabbit 39. Sparrows and Towhees 12. Crows and Ravens 40. Snow Goose 13. Diving Ducks 41. Squirrels 14. Dove 42. Striped Skunk 15. Eagles and Osprey 43. Tanager 16. Eastern Coyote 44. Tundra Swan 17. Elk 45. Vultures 18. Finches and House Sparrow 46. Weasels 19. Fisher 47. White-tailed Deer 20. Flycatchers 48. Wild Turkey 21. Foxes (Red and Gray) 49. Wood Duck 22. Gray Catbird, Northern Mockingbird, 50. Wood Warbler and Brown Thrasher 51. Woodchucks 23. Heron Family 52. Woodcock 24. Kingfisher 53. Woodpeckers 25. Mallard Duck 54. Wrens 26. Mice and Voles
152 Release #007-09 WHITE-NOSE SYNDROME SURFACES IN PENNSYLVANIA By Joe Kosack Wildlife Conservation Education Specialist Pennsylvania Game Commission SHINDLE, Mifflin County – Aware since 2008 that White-Nose Syndrome appeared to be making its way to the Keystone State, the Pennsylvania Game Commission now has evidence that the deadly bat disorder is likely present in a mine near this small community in the state's heartland. Where else this may be occurring and the consequence to bats –a fragile guild of wildlife species – remains an unfolding story. In late December, Dr. DeeAnn Reeder, a biologist with Bucknell University, and Greg Turner, a biologist with the Game Commission's Wildlife Diversity Section, found bats in an old Mifflin County iron mine that exhibited some of the signs of White-Nose Syndrome (WNS), during field investigations into bat hibernation patterns that included weekly monitoring for the disorder's presence in several Pennsylvania hibernacula. During this work, which had been ongoing for weeks, wing dozens of bats suddenly had a fungus appear around their muzzles and on membranes, while many more displayed other symptoms associated with this disorder. Several bats were submitted to the National Wildlife Health Center in PGC Photo/Joe Kosack Madison, Wisconsin, which now is reporting that the bats have preliminarily tested Game Commission In Deep – positive for the cold-loving fungi found on many bats with WNS. Biologist Greg Turner and Dr. DeeAnn Reeder of Bucknell University monitor the signals of transmitters affixed to "Our agency, with assistance from the U.S. Fish and Wildlife Service and other hibernating bats in Shindle Iron Mine. management partners, will work diligently and methodically to measure the extent Get Image of the problem in Pennsylvania and monitor the disorder's progression," said Carl G. Roe, Game Commission executive director. "This find is a direct result of the Game Commission's ongoing initiative to proactively monitor for WNS. "To date, no dead bats have been found in Pennsylvania. That's a plus, but it comes with no promise of what will or won't follow. In New York and New England, the disorder seems to arouse bats from hibernation prematurely. Once they depart from caves and mines, they quickly sap their energy reserves and die on the landscape. Mortality in some colonies has exceeded 90 percent, ensuring that any local recovery will be quite lengthy given the low reproductive rate of bats. Little brown and the federally-endangered Indiana bats produce only one young per year." Currently, researchers still are unsure exactly how bats contract WNS and how it initially and, ultimately, affects a bat's body. They cannot confirm whether the fungus appearing on some bats is a cause or a symptom of the disorder. What is clear is that the geographic area where WNS has been documented is expanding. It was first found in bat colonies in New York in 2006, and subsequently in populations in Connecticut, Massachusetts and Vermont in 2007. Now bats in Pennsylvania and New Jersey appear to be affected. "We do know that the visible fungus appears on some – but not all – bats afflicted with WNS, and that a significant percentage of bats in affected hibernacula move closer to the entrance," explained Turner. "The bats eventually leave their hibernacula – often in daylight, which is unnatural. Most of those bats likely die on the landscape, but some may return to the cave or mine they left. Researchers cannot determine what bats are searching for, or if they're hunting for anything. Most bats found dead on the landscape have depleted their fat reserves." About the only thing certain about WNS is that its ambiguity continues to baffle the cadre of researchers who are working long hours to positively identify what it PGC Photo/Joe Kosack is, and if there is anything wildlife managers can do to disable it. WNS does Troubled Future – A few of these appear to be spreading bat-to-bat, but it's unknown whether it's passed in hibernating little brown bats in summer roosts, or hibernacula, or both. It also is unknown yet whether the Shindle Iron Mine exhibit what is
153 Wildlife Note — 38 LDR0603 Wood Duck by Chuck Fergus The wood duck is our most brilliantly colored duck. . Woodies are excellent swim- ing, finch-like twee twee , can be loosely translated Its scientific name, Aix sponsa mers and fast, agile fliers. Above open terrain they can as "a waterfowl in wedding dress." This shy, retiring bird wing along at up to 50 mph; in woodlands they twist and inhabits ponds and sluggish streams surrounded by wood- turn between the trees, moving their heads almost con- lands. Nicknames include Carolina duck, squealer, sum- stantly in flight. mer duck and woodie. Most authorities place the spe- The wood duck feeds along shores of woodland streams cies with the puddle or dabbling ducks, a group distin- and ponds. A dabbler, it tips its head into shallow water guished by its habit of feeding on and near the surface of and probes the bottom for vegetative parts and seeds of shallow waters, rather than diving for food. pondweeds, wild rice and water lilies. It also eats grapes, Wood ducks range from the Mississippi River east to berries, and nuts — acorns, hickory nuts and beech- the Atlantic coast, and from the Great Lakes Region south nuts — which are swallowed whole and crushed, inside to the Gulf of Mexico. Most of them winter from the the gizzard, into digestible bits. Insects and spiders com- Carolinas south to the Gulf and west to eastern Texas. A prise about 10 percent of the adult's diet, while the duck- small population of wood ducks also inhabits the Pacific ling eats a larger percentage of these high-protein ani- Northwest. In Pennsylvania, woodies are common mi- mal foods. In winter, wood ducks may turn to waste corn grants in March and April; summer breeding residents; if natural foods are scarce. common migrants in September, October and early No- Breeding occurs in late March and April, extending vember; and occasional winter residents in the south- into May in the north. Most pairs form on the wintering east and southwest corners of the state. range, following an intense courtship. The male preens behind his wings, spreading them to show off their iri- Biology descent sheen, he tucks in his chin, erects his crest, and fans his tail. He swims at the hen then circles her. An adult wood duck is 18 to 20 inches long, has a 24- When the birds migrate north, the hen homes in on inch wingspan, and weighs 1½ pounds. The male is called last year's nest tree or, if she is a yearling, on the same a drake, the female a hen. The drake's coloration is noth- general locale in which she was hatched. The male sets ing short of exotic. His head is iridescent green, shading up no actual territorial boundaries, but will defend his into blue and purple, with a slicked-back crest of feath- mate from the attentions of other males. Several breed- ers and a white chin-bib. His eyes are bright red, his bill ing pairs may share the same pond. Nesting concentra- reddish-orange, his legs yellow. His chest, a rich chest- tions are largely determined by the availability of nest nut, is separated from his golden-yellow sides by vertical sites. The mated hen seeks out a cavity in a tree; the male bars of white and black. The hen's plumage is drab, a com- follows her on these search flights, but the hen appar- bination of gray, white and brown. She has a small head ently picks the exact spot. crest and a circle of white surrounding Wood ducks prefer to nest each eye. in trees standing over Wood ducks do not water, but sometimes quack. The hen, more will settle for sites up vocal and louder to a mile away. They than her mate, normally use natural squeals a shrill cavities with en- warning call, hoo-eek trances too small for hoo-eek . The drake raccoons to enter, of- whistles an ascend- ten choosing excava-
154 inconsistent state plans. The wood duck was also aided tions made by pileated woodpeckers. They also nest by Pennsylvania's beaver reintroduction program, which readily in man-made boxes. began in 1917, and the construction and placement of The hen lays 8 to 15 eggs (one per day) in the bottom thousands of wood duck nest boxes by conservation or- of the cavity, on accumulated wood chips covered with ganizations. down from her breast. The eggs are dull-white and un- The wood duck population grew steadily. In 1941, marked. Incubation, by the female alone, starts with the hunting was again permitted. In 1976, waterfowl scien- last egg and takes about a month. Unlike most other male tist Frank Bellrose reviewed many local studies and con- ducks, the drake woody stays with his mate well into her cluded that the adult population of wood ducks is about incubation. He has usually left the scene, though, by the 1 million before each year's breeding. Others have esti- time the eggs hatch. mated the annual post breeding population at 2½ to 3½ All the eggs hatch on the same day. The hen usually million. keeps her brood in the nest overnight, and then in the Today the wood duck has reclaimed most of the At- morning she flies out and lands on the ground or water lantic Flyway and a large part of the Mississippi drain- below, where she begins calling softly. The day-old duck- age. The greatest concentration of woodies lies in lings leap out of the nest to join her. They tumble down Ontario. perhaps 60 feet, sailing like cotton puffs and usually land- ing unharmed. The hen leads them to safety along a lake Habitat or a stream. If a raccoon, snake or squirrel destroys her first clutch, Wood ducks inhabit slow-moving creeks, woodland the female may lay a second. A few hens raise two broods, but the vast majority raise only one. ponds, lakes, swamps, marshes and beaver ponds. They Ducklings — and adults — are preyed upon by minks, rest in thick growths of water lilies, smartweeds and other otters, raccoons, hawks and owls. In Maryland, scientists emergent plants; hens hide their ducklings in vegetation, under overhanging banks and among fallen, partly sub- found that half of the young were killed in their first month. The brood begins to break up after six weeks or merged trees. so, and the young can fly when two months old. Woodies nest in cavities of mature sycamore, maple, After leaving his incubating mate, oak, basswood, elm and gum trees. Where big trees are scarce, they will use man- the drake woody joins other male made nest houses. Artificial nests wood ducks in the dense cover should be made predator- of a swamp or wooded pond. proof, as they attract rac- Here he molts into eclipse coons, squirrels and other plumage: dull feathers re- sembling the drab plumage predators looking for a of a hen. During part of the meal. Place nest boxes on poles over water; attach annual summer molt, wood ducks — both drakes and, metal shields partway up the poles, and make sure the later, hens — lose their wing boxes' entrances are small feathers and cannot fly. In late summer or early fall, a enough to exclude raccoons. second molt begins, restor- Studies in Pennsylvania show that hens and broods ing the normal plumages. having to travel more than Wood ducks migrate south a mile from their nest box to for the winter. Some seek out brood-rearing wetlands expe- common roosting and feeding sites, rience the highest mortality. That's why it's a good idea grouping in flocks of less than a hundred to several thou- sand. Pennsylvania band surveys show most of our home- to place nest boxes near suitable wetlands. Wood duck grown woodies winter in the Carolinas, Georgia and boxes also provide nesting space for American kestrels, Florida. common screech owls, mergansers, squirrels and occa- sionally, wrens and tree swallows. Plans for the boxes can be obtained by writing: Pennsylvania Game Commission, Population Dept. MS, 2001 Elmerton Avenue, Harrisburg, PA 17110- In the early 1900s, the wood duck was nearing ex- 9797. tinction. Many woodland ponds, the species' favorite habitat, had been drained. Widespread logging had re- moved the mature trees needed for nesting. And for years Wildlife Notes are available from the the woody had been hunted hard for its good-tasting flesh. Pennsylvania Game Commission In 1913, wood duck hunting was banned for five years Bureau of Information and Education by the U.S. Department of Agriculture to spur a popula- Dept. MS, 2001 Elmerton Avenue tion recovery. That effort was followed by the ratifica- Harrisburg, PA 17110-9797 tion of the Migratory Bird Treaty Act between the United www.pgc.state.pa.us States and Canada, which established the framework needed to manage waterfowl on a broader scale than with An Equal Opportunity Employer
155 Wildlife Note — 47 LDR0103 ood ood W W ood W ood ood W W arblers arblers W W arblers W arblers arblers W W by Chuck Fergus Like jewels strewn through the woods, our native war- blers appear in early spring, the males arrayed in gleaming colors. Twenty-seven warbler species breed commonly in Pennsylvania, another three are rare breeders, and seven migrate through Penn's Woods for breeding grounds far- Yellow Warbler ther north. In central Pennsylvania the first species begin arriving in late March. The great mass of warblers passes through between May 10 and 15, and then the migration trickles off until it ends in late May — by which time the trees have leafed out, making it tough to spot canopy-dwell- Protonaria citrea widely. The prothonotary warbler ( ), a rare ing species. breeder in wetlands and bottomland forest in Pennsylva- In southern Pennsylvania, look for the migration to be- nia, builds its nest in a tree cavity, often an old downy wood- gin and end a few days to a week earlier; in northern Penn- Vermivora ruficapilla ) pecker hole. The Nashville warbler ( sylvania, it's somewhat later. In August warblers start mov- is one of several species that nest on the ground. Some ing south again, with migration peaking in late September warblers nest exclusively in conifers; others use hardwood and ending in October, although stragglers may still come trees. The northern parula warbler ( Parula americana ) through into November. But by now most species have weaves its nest into hanging clumps of lichens, twigs or pine molted into cryptic shades of olive and brown: the "confus- needles. Most species are monogamous. Generally the fe- ing fall warblers" of field guides. male builds the nest. The eggs, usually two to five per clutch, The wood warblers (subfamily Parulinae) are found only are whitish with dark spots. Typically the female does most in the New World. The group includes 110 species, with or all of the incubating, and both parents feed the young. more than 50 found regularly in North America. Wood We know less about warblers' habitat requirements and warblers are small lively birds that use a range of habitats. feeding activities on their winter range. Most species win- All of the North American species are migratory; almost ter in Mexico, Central America and South America, where certainly, most developed in the tropics and extended their they forage in mixed flocks with several to many different ranges northward to exploit new breeding zones. species. Wood warblers tend to shun lowland rain forests, The name "warbler" is a misnomer, because few species preferring foothill and mountain forests instead. A few hardy possess warbling voices and many have thin, scratchy, un- species (the yellow-rumped warbler, Dendroica coronata , is musical songs. Males use two calls: a song to advertise terri- one) stay in North America all winter. tory, and a shorter call to attract a mate and to communi- Warblers are small birds with limited fat reserves, and cate with her. many perish from the rigors of migrating. A route followed Wood warblers breed in May and June, in woods and by many species in spring requires a nonstop flight from the brushland, in areas that may be dry, moist or wet. They Yucatan Peninsula across the Gulf of Mexico to Louisiana, forage from ground level to the treetops and eat mainly Mississippi, Alabama and Florida. If migrating birds encoun- small insects plus a few fruits; some warblers take flower ter headwinds, many exhaust their strength, fall into the nectar. When several species inhabit the same area, their ocean and drown. Tremendous numbers of warblers and feeding strategies are usually different enough that they don't other night-migrating birds die when they fly into commu- compete directly with one another. Nesting habits vary nications towers and tall buildings, particularly on cloudy
156 nights. Many individuals are killed by the smaller hawks nests or to build a new nest on top of the cowbird eggs. and owls. Warblers have been documented to live for more Yellow warblers arrive in Pennsylvania in April and May than 10 years in the wild, but most die before reaching that and head south again as early as July or August. They win- ter in Mexico, Central America and northern South age. America. Some wood warbler populations are holding their own. Those of others, such as the cerulean warbler ( Dendroica ), which breeds in mature forests, have declined. cerulea )—In ( Chestnut-Sided Warbler Dendroica pensylvanica spring, both sexes sport a yellow crown, black face mark- ings, and chestnut streaks on their sides. The song is similar please please to the yellow warbler's and has been rendered as please ta meetcha . This now common species increased its numbers after Pennsylvania's virgin forests were logged. Chestnut-sided warblers inhabit brush and briers, slashings Black-and-White of cut-over woods and reverting fields. They forage for in- Warbler sects by hopping from branch to branch, darting out now and then to intercept prey in midair. The nest is built in low, dense shrubs or blackberry tangles, and is woven out of strips of cedar or grapevine bark, weeds, grasses and roots, with a soft lining. Immature birds and adults in autumn wear a dull greenish plumage and look not at all like their bright spring selves. The winter range extends from Mexico through Panama. Dendroica ( Black-Throated Blue Warbler ) — One of the handsomest birds in the forest, caerulescens the black-throated blue is aptly described by its name. (The slatey blue is set off by a white breast.) The species typi- cally nests in deep woods, often in cove forests well stocked with hemlocks, with a bubbling stream nearby and plenty of gnats, moths, crane flies, caterpillars, and other insects. Males usually forage higher in the understory than do fe- males; some black-throated blue warblers steal insects from . zur, zur, zree spider webs. Males sing a buzzy, drawn-out The nest is a bulky cup hidden in a rhododendron, laurel, When northern woodlands are broken into smaller patches or shrubby conifer. The species nests commonly in the by logging or home development, warblers lose habitat. In mountains of northern Pennsylvania and north into fragmented woods, native birds and mammals, including Canada; it winters in the Bahamas and the Greater Antilles. blue jays, raccoons, foxes and squirrels, and feral house cats can prey more easily on warblers and their nests. Brown- headed cowbirds, which live in open areas, find greater ac- cess to warblers' nests: The female cowbirds surreptitiously lay eggs in the nests, and when the young cowbirds hatch, they are raised by the host adults, whose own smaller, American slower-to-develop young usually don't survive. Redstart Following is a closer look at eight common wood war- blers of Pennsylvania. Yellow Warbler ( Dendroica petechia ) — This showy all-yellow bird has a rufous-streaked breast. The male's song is a lively weet weet weet weet tsee tsee . The most widespread of all wood warblers, the species breeds statewide in Penn- sylvania. Look for yellow warblers in low brush or shrubs, woods edges, orchards, parks and gardens; they're often found along streams and near swamps. Caterpillars may make up two-thirds of the diet. Yellow warblers also snatch up mayflies, moths, mosquitoes, beetles, damselflies, treehoppers and other insects, plucking their prey from twigs and leaves, hovering to glean from the un- dersides of foliage, and making short flights. The nest is a neat open cup built of plant materials and lined with plant down or fur. Yellow warblers are often parasitized by cow- birds. Foreign eggs cause some yellow warblers to desert their
157 Black-and-White Warbler Mniotilta varia ) — This abun- ( Louisiana Waterthrush dant bird acts more like a nuthatch or a creeper than a war- bler, foraging methodically in tree bark, circling trunks and limbs of trees while looking for insects and their eggs. Both males and females have zebra stripes on their back and crown. Next to the Louisiana waterthrush, the black-and-white warbler is the earliest spring migrant; individuals are easily observed before the leaves push out. They often feed low in trees and usually nest on the ground in deciduous woods. weesee, weesee, weesee , etc., repeating The male sings a thin the phrase at least seven times. The female builds a nest out of dry dead leaves and lines a central cup with grasses, strips of grapevine bark, rootlets and weed fibers. The nest is built at the base of a tree or tucked partway under a log, stump or rock. Cowbirds often heavily parasitize black-and-white war- blers. Black-and-whites winter in Florida, the Gulf Coast states, the West Indies, and from Mexico south into South America. American Redstart ( Setophaga ruticilla ) — Males are an eyecatching mix of black, orange and white; orange patches ) — In April, Louisiana Waterthrush ( Seiurus motacilla show on the wings and tail, which the bird often flashes trout fishermen see this shy warbler walking on stones along open and shut. Redstarts flutter about in treetops, hovering the edges of streams, turning over wet leaves with its bill among leaves, leaping up or darting out like a flycatcher to and flitting out over the water to catch prey. A Louisiana grab a passing insect: A redstart even has bristles framing its waterthrush looks like a thrush and acts like a sandpiper, mouth to help it catch flying prey. The song is a series of teetering and dipping, elevated above slick rocks on its long high-pitched, indistinct notes. American redstarts in- tsee legs, stabilized by large, long-toed feet. Waterthrushes eat habit sapling woods, river groves, forest edges and treelined bugs, beetles, adult and larval mayflies, dragonflies, crane creek banks. A Wisconsin study found the species to be three fly larvae, ants, caterpillars and other insects, plus centi- times as common in woods of greater than 80 acres than in pedes, small crustaceans and snails. They breed from April woodlots comprising less than 14 acres. In Pennsylvania the to June along rushing brooks, sluggish swamp streams, and American redstart is rare in the highly agricultural south- moist hillsides, always in woods. Pairs build their nest in a east, common in the forested northcentral and northeast. hole in the stream bank, hidden by tree roots, weeds or grass. Redstarts eat insects, spiders, seeds and berries. The female Louisiana waterthrushes nest throughout the East; they win- builds a cup-shaped nest in a tree fork 4 to 70 feet in the ter in streamside forests in Mexico, Central America, the air. Some males breed with more than one female in their Bahamas and the Greater Antilles. territories. Redstarts head south in August and Septem- ber; they winter in the Gulf Coast states and from Mexico south to South America. The species is named after a Eu- ropean bird whose name means "red tail." ( Seiurus aurocapillus ) — This bird gets its name Ovenbird from the covered dome-shaped nest it builds on the ground; early observers were reminded of a Dutch oven. An oven- bird looks like a little thrush, olive-brown above and with a dark-streaked (rather than a spotted) breast and an orange, black-rimmed stripe atop the head. Ovenbirds prefer dry mature deciduous woods, but they also inhabit other forest types including swamplands; they do best in extensive wooded tracts. Ovenbirds feed on the ground, taking beetles, ants, caterpillars, bugs, worms, spiders and snails. The song Teacher! Teacher! Teacher! , repeated about 10 is an emphatic times at increasing volume, three to four sessions per minute. The species nests statewide, although it's absent from heavily farmed and urbanized districts. The ornithologist Hal Harrison found cowbird eggs in six of seven Pennsylvania ovenbird nests that he monitored one summer, but research at Hawk Mountain Sanctuary found that few nests in deep Common Yellowthroat forests contained those unwanted guests. Ovenbirds arrive here in April and May, depart in Sep- tember and October, and winter in Mexico, Central America, Florida and the Caribbean.
158 Common Yellowthroat )— Witchity, ( Geothlypis trichas witchity, witchity sings this bird with the gray back, black mask, yellow throat and whitish belly. (Females lack the black Ovenbird mask.) In Pennsylvania, yellowthroats nest in cattail marshes, alder swamps, shrubby bogs, wet meadows, forest edges and openings, and old fields. They like thick briary cover and take advantage of small habitat patches: An ornithologist once found 17 nests in a half-acre swamp in Illinois. As the result of this broad habitat use, they are the most widespread of the warblers. Nests are built on or near the ground, hidden in tus- socks, weed stalks and shrubs; they're bulky, made of dry leaves and coarse grasses lined with finer plant matter. Yel- lowthroats eat insects (grasshoppers, dragonflies, mayflies, beetles, moths, ants, aphids and many others), spiders and seeds. They nest statewide across Pennsylvania and winter in the southern United States, Mexico and Central America. Illegal draining and filling of wetlands — even very small ones — harms yellowthroats and many other forms of wild- life. Yet the population of this spunky, active bird has in- creased in recent years in the Keystone State. tucky, mourning, hooded and Canada, and the northern waterthrush and yellow-breasted chat. Rare breeders include The other breeding warblers in Pennsylvania are the blue- blackpoll, prothonotary and Swainson's warblers. Seven winged, golden-winged, Nashville, northern parula, mag- other warblers migrate through Pennsylvania: Tennessee, nolia, yellow-rumped, black-throated green, Blackburnian, orange-crowned, Cape May, bay-breasted, palm, Connecti- yellow-throated, pine, prairie, cerulean, worm-eating, Ken- cut and Wilson's. Wildlife Notes are available from the Pennsylvania Game Commission Bureau of Information and Education Dept. MS, 2001 Elmerton Avenue Harrisburg, PA 17110-9797 www.pgc.state.pa.us An Equal Opportunity Employer
159 Wildlife Note — 6 LDR0103 Woodchuck by Chuck Fergus Known by many names — chuck, groundhog, whistle gardeners. In the summer, woodchucks feed most actively pig, marmot, monax and others — the woodchuck is a during early morning and late evening. common Pennsylvania game animal. Members of the or- A woodchuck has keen senses of sight, hearing and der Rodentia (rodents) and family Sciuridae (squirrels), smell. Note where the animal's sensory organs are located woodchucks are closely related to tree and ground squir- on its skull: eyes, ears and nose are all near the top of the rels, chipmunks, prairie dogs and marmots. Chucks dig head, enabling a groundhog to check its surroundings burrows; these holes aerate the soil and provide excel- simply by sticking its crown out of the burrow. When lent escape hatches for many other animals, but they are feeding, a chuck usually raises its head every 10 seconds dangerous to livestock and farm machinery. So the wood- or so to check for danger. chuck is often thought of as a "valuable nuisance" — a A muscular body, short powerful legs and sturdy claws contradiction in terms that illustrates well this inhabit- make the chuck an excellent digger, and the critter spends ant of field and fencerow. much of its time underground. It piles excavated dirt at its burrow's main entrance and often sits on this mound Biology to look about. The burrow descends at a sharp angle be- low the entry hole and then levels off into a narrower , is a mammal about Marmota monax The woodchuck, tunnel. Woodchucks often dig many side tunnels and two 20 to 26 inches long, including a bristly, 6-inch tail. or three back entrances. These "drop holes" are incon- Weights of adult chucks vary from 5 to 10 pounds, with spicuous — they aren't marked with dirt mounds — and extremely large animals as heavy as 12 to 15 pounds. chucks use them as lookouts or to get underground in a The weight of an individual fluctuates in a cyclic fash- hurry when danger threatens. Burrows are usually located ion throughout the year, with the animal at its heaviest in well-drained, sloping areas and rarely get flooded. In by summer's end. digging, chucks use their strong forefeet to loosen the Woodchucks have yellowish-brown to blackish-brown soil, then their hind feet to kick the earth behind them. fur. Belly fur is sparse and usually paler than the fur on Even though a groundhog has short legs, it can run at the back. The pelt is coarse and has little or no commer- a fairly fast clip for a short distance. An adult is a fierce cial value. Light-colored hairs in the coat give some in- fighter; dogs, coyotes and foxes are about the only en- dividuals a grizzled appearance. Albinism and melanism emies it has, although young chucks are preyed upon by occur infrequently. A chuck's feet are dark brown or owls and hawks. Woodchucks climb well, ascending and black, and its front incisor teeth are white. These two descending trees head first. They have good balance and front teeth are broad and chisel-shaped like those of rab- frequently walk along wooden fence rails. They use their bits and squirrels and are used primarily to nip off veg- front paws much as people use their hands, to clutch stems etation. They identify the woodchuck as a rodent. of clover or hold apples while feeding. Woodchucks are found throughout Pennsylvania in Woodchucks can produce several sounds. They often open fields, meadows, pastures, fencerows and woodland let out a sharp whistle for an alarm call. When feeding, edges and even deep in the woods. Adults rarely move they may make a "chuck-chuck" sound, and when angry more than a half mile within their home ranges, prefer- or cornered may chatter their teeth. ring to stick close to the safety of the burrow. Woodchucks hibernate during winter. They eat Chucks don't generally have to move far to find food, heavily throughout summer and early fall to accumulate as they eat a wide variety of vegetation — including body fat and prepare to shelter in their burrows all win- green grasses, weed shoots, clover, alfalfa, corn in the milk ter. With the hard frosts of October, chucks begin den- stage, dandelion greens, garden vegetables such as beans, ning up; few remain active past the first of November. A peas and carrots and, in the fall, apples and pears. These hibernating animal goes into a deep sleep, or a dormant feeding habits often get them in trouble with farmers and state: its body temperature, heartbeat and other meta-
160 tion size depends on habitat, and while woodchucks can bolic processes fall off drastically as the animal lives over exist in wooded territory, they don't build up sizable winter on its body fat. (A chuck's body temperature drops populations there. By cutting forests, raising crops and from over 90 F into the low 40s; heartbeat slows from clearing pasture land, settlers provided suitable habitat more than 100 beats a minute to only four.) and the woodchuck population expanded. Today the In the spring, males emerge from hibernation before chuck is one of our most common mammals. females, and during February and March fight aggres- Woodchuck numbers vary from area to area, depend- sively. Fat left over from hibernation sustains chucks ing on food availability, soil type, hunting pressure and during mating season (late February to March), when suc- predation. Sometimes populations are extremely dense, culent green foods are scarce. After a 28-day gestation with up to six or seven individuals per acre; this high period, females bear young in April and early May. Lit- density is seldom reached. A population of four per acre ters average 3 to 4 young; newborn chucks are blind, na- is considered abundant, and the average is probably ked and helpless and remain in the underground nest closer to one per acre of farmland. until about a month old. By mid-June or early July, they In some regions, woodchucks are under heavy hunt- are ready to leave the home burrows and establish their ing pressure but still produce high populations year af- own territories. ter year. This illustrates how a game species can absorb This move is a perilous one for young woodchucks, heavy local losses if it has enough good habitat. Chucks and many are killed by vehicles or fall prey to dogs and can damage crops and gardens and become real pests in foxes. The young often take up residence in abandoned agricultural areas where they are overabundant. dens. As fall approaches, they have to feed more actively As a species, the woodchuck has a large range, ex- than the heavier adults in order to accumulate enough tending north and northeast from Oklahoma and Ala- fat to last them through the coming winter. bama, and west across Canada into Alaska. The yellow- The potential lifespan of a woodchuck is estimated at belly marmot, closely related to the woodchuck, inhab- eight or nine years. In a study conducted at the Penrose its the high country of the Rocky Mountain states. Research Laboratory, Philadelphia Zoo, observers found that captive woodchucks died of many causes, including Habitat cancer of the liver, ruptured aortas, heart attacks, and cerebral strokes resulting from hardening of the arteries. Woodchucks live in many types of terrain, from farm- It's doubtful whether many chucks in the wild live to be land and old, overgrown cemeteries to orchards and sub- eight years old. Enemies shorten this period, and the older urban areas. Ideal habitat might be a thick, almost im- an adult woodchuck gets the more easily it falls prey to penetrable fencerow bordering cultivated cropland. Or- predators. chards, especially if the spaces between trees are not A few chucks are affected by malocclusion, which mowed frequently, provide good habitat; woodchucks dig occurs when the front incisors fail to meet and therefore burrows under dead stumps or at the bases of the trees, can't continually grind each other down. A rodent's teeth where the roots protect den entrances. In stony areas, never stop growing, so this misalignment may result in dens are often dug under large rocks. an incisor growing in a complete circle, sometimes even A chuck may dig its burrow in the center of a field or penetrating the skull cavity and killing the animal. pasture, but usually the animal chooses a more protected location such as a field edge, fence, hedgerow or under a Population stone wall. Apparently, chucks do not require ground water sources as many live far from streams, lakes, creeks The woodchuck is one animal that has benefited from and other bodies of water. Like rabbits, they get mois- civilization. When our state was wilderness — when the ture from succulent plants, dew and water left standing land was almost completely forested and there were no after rainfalls. farms, pastures or orchards — there were far fewer wood- As well as requiring habitat, woodchucks provide it chucks than there are today, with the tunnels they dig. Skunks, raccoons and foxes simply because there was remodel vacant burrows and use them to bear and raise little suitable habitat. young. Foxes may claim a burrow after killing its wood- Probably the only places chuck owner. Rabbits often seek shelter in the dens, es- where chucks became pecially during winter while the chucks are hibernating abundant were on for- below. Animals pursued by predators or hunters also use merly forested tracts that the burrows as escape hatches. had been swept clear by fires and were growing up again in brush. But as these natu- Wildlife Notes are available from the rally-cleared areas Pennsylvania Game Commission matured, Bureau of Information and Education woodchuck Dept. MS, 2001 Elmerton Avenue numbers Harrisburg, PA 17110-9797 would have www.pgc.state.pa.us dwindled; popula- An Equal Opportunity Employer
161 Wildlife Note — 21 LDR0603 Woodcock by Chuck Fergus of year. ) is known The American woodcock ( Scolopax minor A woodcock's bill is long and thin. A female's bill by a host of folk names: timberdoodle, night partridge, measures 2¾ inches or slightly longer, while a male's is big-eye, bogsucker and mudsnipe. It's a strange little usually less than 2½ inches. Sensitive nerve endings in creature with big eyes and a bill that looks too long for the lower third of the bill help a woodcock locate earth- its body. Most active at dusk, night and dawn, a wood- worms. A special bone-muscle arrangement lets the bird cock uses its bill to probe rich soil for earthworms, its open the tip of its upper bill, or mandible, while it's un- favorite food. derground. The long tongue and the underside of the Woodcock are migratory. While a few birds from far- mandible are both rough-surfaced to grasp and pull slip- ther north may wait out an exceptionally mild winter on pery prey out of the ground. Pennsylvania's southern fringe, most timberdoodles pass Eyes are large and set well back and high on the sides through our state. They spend the cold months in the of a woodcock's head. Naturalists have speculated that South — the Carolinas, Georgia and northern Florida this positioning lets the bird look all around — behind, west to eastern Texas and Arkansas, concentrating in above and to the sides, as well as ahead — while it probes Louisiana and southwestern Mississippi. In spring, wood- for food. Nostrils are set high on the bill, close to the cock return north. skull. A woodcock's ears are ahead of the eyes, between Taxonomically, the species is placed in Order the base of the bill and the eye sockets. Hearing and sight Charadriiformes, which includes gulls, oystercatchers, are acute. plovers, stilts, curlews, sandpipers, snipe, phalaropes and The woodcock's brain is unique among birds. Its cer- others. Within this large order, the woodcock belongs to ebellum — which controls muscle coordination and body Family Scolopacidae, a group of snipe and sandpipers with more than 80 species distributed over most of the world. The American woodcock is closely related to the Eu- ropean woodcock ( Scolopax rusticola ). The Old World bird resembles its American counterpart and has a simi- lar life history, but it's larger and almost twice as heavy. Biology A timberdoodle's plumage is an overall mottled rus- set and brown. The beige breast, back and sides are over- laid with black and browns; the forehead and crown are ashy gray to black, barred with gold. The short tail is a combination of brick-red and black, tipped with gray. Feet and toes are bare and gray- to flesh-colored. A woodcock is 10 to 12 inches in length (a little longer than a bobwhite quail), has a standing height of about 5 inches and a wingspread to 20 inches. Body conforma- tion could be described as "chunky" — short and heavy, with a short, thick neck and a large head. Wings are short and bluntly rounded. Sexes look alike, although females generally average a bit heavier than males (7.6 vs. 6.2 ounces). Weights for both sexes vary according to time
162 Females seek out males on the singing grounds. Males balance — is located below the rest of the brain and may mate with several females. In Pennsylvania, most above the spinal column. (In most birds, the cerebellum breeding takes place from early March to mid-May. Both occupies the rear of the skull.) One theory suggests that, sexes breed in their first year on the breeding grounds as the woodcock evolved, the eyes moved back in the (before they're a year old). skull, the bill lengthened, and the nostrils approached Hens usually nest within 150 yards of the singing the base of the bill — adaptations that permitted ground- grounds where they mated; males play no role in nest probing. As a result, the brain was forced back, and the selection, incubation or rearing of young. Favored nest- mid-brain and hind-brain were pushed down and slightly ing habitat includes damp woods near water, hillsides forward. The woodcock of today, in essence, has an up- above moist bottomlands, old fields with low ground side-down brain. cover, briar patches, the edges of shrub thickets and When woodcock flush from the ground, air passing young conifer stands. There may be little overhead cover through their rapidly beating primary wing feathers pro- (old fields) or up to 50 feet of vegetation (hardwood duces a whistling sound. The birds usually flutter up out stands). The average cover height is 12 feet. of cover, level off and fly from 10 to several hundred A typical timberdoodle nest is a slight depression on yards before setting down. Being migratory birds, they the ground in dead leaves. Some nests are rimmed with are capable of sustained flight. twigs or lined with pine needles. An egg-laying or incu- Food: Earthworms, high in fat and protein, make up bating hen is difficult to spot, as her mottled, brown plum- about 60 percent of a woodcock's diet. An addi- age usually blends in with the background. tional 30 percent is insects (ants, flies, beetles, In Pennsylvania, woodcock nest from crickets, caterpillars, grasshoppers and vari- late March into June. Located near ous larvae), crustaceans, millipedes, cen- nesting sites are feeding areas tipedes and spiders. About 10 percent of open woods, abandoned is plant food, mostly seeds from fields, brushy areas and bristlegrass, panicgrass, sedge, rag- mixed forests, where incu- weed, knotweed and blackberry. bating hens feed. Although Timberdoodles do most of their they are solitary nesters, feeding in the early evening hens may share feeding and just before dawn. Diges- grounds with other tim- tion is rapid; an adult may berdoodles. A female lays eat its weight in worms one egg a day until she each day. completes the normal Woodcock are clutch of four. Eggs are oval, 1½ by quite vocal; natural- 1 inch, which are large for the bird's size. The shells are ists have recorded smooth, with a slight gloss, colored pinkish-buff to cin- least 10 separate and interpreted at namon and covered with light brown blotches overlaid ing season, a male tim- calls. During the mat- with darker speckling. berdoodle on the ground will sound a nasal, buzzing, in- Incubation takes 19 to 22 days. It begins after the last sect-like note usually described as peent . Preceding each egg is laid, so all eggs receive equal incubation and hatch is a two-syllable gurgling note, tako peent . While the peent at about the same time. If a hen is disturbed early in the is tako carries several hundred yards, the much softer incubation period, she may abandon the nest. The longer audible only within about 15 feet of the bird. she sits on the eggs, however, the less likely she will desert chirps — The flight song — a series of liquid, gurgling them. Toward the end of the incubation period, she may is sounded by a male trying to attract a mate. A male sit tight even when touched by a human's hand. Nest defending breeding territory against another male calls predators include domestic dogs and cats, snakes, skunks, cac-cac-cac-cac as he flies toward his rival. A female will opossums, raccoons and crows. Fires and flooding also squeal and often feign a broken wing to lure intruders destroy nests. Hens losing their first clutch may re-nest, away from her young. Other calls express alarm or pro- often laying only three eggs. Eggs hatch from early April vide communication between hens and offspring. Migrat- until mid-June, peaking in our state during the last week ing woodcock have turned up in Pennsylvania as early as in April and the first week in May. February 25, but most don't arrive until the last two weeks Chicks: Eggs split lengthwise (unique among birds) as in March. Migration is complete by mid-April. the woodcock chicks emerge. Chicks are precocial, able Reproduction: In spring, males establish territories to leave the nest a few hours after hatching. They're cov- known as "singing grounds." These are woodland clear- ered with fine down, pale brownish to buff with brown ings spotted with low brush, or open fields next to brush spots and stripes above, and rufous below; a dark line or woods; they vary in size, but a quarter-acre seems big runs from the bill back to the eye. From the day of hatch- to attract enough. While on the ground, the males peent ing, chicks "freeze" when threatened or in response to females. A male will take off and fly upward 200 to 300 the hen's alarm call. During the first few days, the hen feet on twittering wings; then he'll spiral or zig-zag back broods her chicks frequently, especially during rain, snow to earth, sounding a liquid, warbling song as he descends. or cold. At first she finds worms for them, but after a few Courtship occurs for short periods at dawn and dusk; it's days, they are probing for and capturing worms by them- most active when temperatures are above freezing and selves. winds are calm.
163 may be scattered, concentrated, or absent, depending on Chicks grow rapidly. After two weeks they can fly short time of year, weather conditions or habitat. In autumn, distances, and at the end of four weeks they're almost fully concentrated groups of woodcock may not reflect the grown, fly strongly and look like adults. The family breaks carrying capacity of land on which they're found, as they up when juveniles are 6 to 8 weeks old. Adults undergo a may just be passing through. The overall population can complete feather molt during the summer; juveniles un- fluctuate greatly over the years. Steady human encroach- dergo a partial molt from July to October. ment on wet woodland, timber maturation and flooding Migration: As days grow shorter and temperatures drop, may pose threats to the woodcock population. timberdoodles begin to head south. Woodcock migrate Woodcock may be exposed to pesticides used to con- at low altitudes (about 50 feet), flying at night and rest- trol either forest or agricultural pests. Contamination from ing and feeding in secluded thickets during the day. They agricultural pesticides is highest in wintering areas where typically travel alone. Birds from farther north may start woodcock feed in farm fields. Earthworms are resistant to to pass through Pennsylvania in October; the migration many chemicals, so they can carry toxins. Since wood- peaks in late October and early November, with strag- cock are predators of earthworms, there's a chance they'll glers up until the end of November. Heavy northwest accumulate persistent toxic chemicals found in worms. winds and cold nights may start large numbers of timber- From 1968 to 1997, Pennsylvania's woodcock popula- doodles winging south. tion had declined about five percent annually. That com- Wildlife biologists believe that woodcock have sev- pares to a two percent average annual decrease over the eral migration routes. Most woodcock nesting east of the same period throughout its North American range. Most Appalachian Mountains appear to winter mainly in the biologists attribute this decline to loss of habitat quan- south Atlantic states. Woodcock breeding west of the Ap- tity and quality. In Pennsylvania, intensive logging, farm palachians are thought to winter in Arkansas, Louisiana abandonment and wildfires that create new and young and other Gulf States. In spring, woodcock reverse direc- forests — highly desirable woodcock habitat — are rela- tion and return north; like many migratory birds, they tively rare today. Development also destroys or fragments home strongly to the areas where they hatched. existing woodcock habitat. Woodcock are hardy and seem able to recover from injuries that would kill most other birds. If a timberdoodle Habitat reaches adulthood, its life expectancy is about 1.8 years. Banded wild birds seven years old have been recovered. Habitat requirements for woodcock change through- Mortality factors include predators; accidents, many oc- out the year. In spring, they need areas for courtship and curring during night flight; hunting; disease; parasites and nesting; in summer, for brood-raising; during fall and spring bad weather. Woodcock heading north too early in spring migrations, for feeding and resting; and they require win- may be caught by late-season snows or hard freezes, which tering habitat in the southern states. Food must be avail- seal off their food supply. able during all seasons. As migratory birds, woodcock fall under the jurisdic- Woodcock are attracted to moist forestland in early tion of the U.S. Fish & Wildlife Service. This agency stages of succession. They tend to use edges rather than monitors the species' population and sets the framework interiors of big, even-aged thickets. The following plants for hunting seasons and bag limits. make land more attractive to timberdoodles: alder, as- pen, hawthorn, gray dogwood, crab apple, blue beech and Population gray birch. These species can be planted or, if they al- ready grow in a given area, encouraged by cutting down Compared to most other game birds, woodcock have a large trees which may be shading them and stunting their low potential productivity. A female raises only one brood growth. For courtship, males need singing grounds — each year, and each brood consists of four (and sometimes clearings a quarter-acre or larger, with a straight, unim- only three) young. Fortunately, the species has a high peded take-off strip 15 to 20 yards long. As trees and nesting success rate — 60 to 75 percent — and low juve- shrubs in the clearing grow larger, woodcock will seek out nile mortality. other areas; to keep a singing ground functioning, it must Population densities vary in any one locale. Woodcock be cleared periodically. Females nest and raise broods near breeding grounds. Good cover includes edges of thickets, young conifer plan- tations and old, brushy fields. The best feeding areas are shrub patches near streams, springs or marshy ground; resting cover often is on high, drier ground. Feeding and resting cover is used by hens and broods, males and migrating timberdoodles. The life of good woodcock cover is about 20 to 25 years in Pennsylvania. As the cover matures, different tree species take over, and it grows less suitable. Over-mature aspen and alder tracts can be cut or burned; the resulting shoot growth will restore good habitat.
165 Wildlife Note — 13 LDR0103 Woodpeckers by Chuck Fergus A drumroll at dawn, a bird in undulating flight through blows from alternating directions — much like a wood the forest, wood chips littering the ground at the base of chopper does. Bones between the beak and the unusu- a tree — all these signal the presence of a woodpecker, a ally thick skull are not as rigidly joined as they are in highly specialized and important member of nature's other birds. Spongy, shock-absorbing tissues connect highly complex world. these flexible joints; strong neck muscles provide force Woodpeckers have been around for a long time: their for drilling; and bristly feathers shield the nostrils from fossil remains date back 25 million years and they're dust and wood chips. widely distributed, with 45 species in the US and more The tongue of most woodpecker species is round, than 200 worldwide. Nine species either live year-round horny and rich in tactile cells. The tip is pointed and in Pennsylvania or visit the state in winter. The common barbed. After chopping exposes a woodborer's cavity, the flicker (yellow-shafted phase), pileated woodpecker, red- long, flexible tongue feels out, impales and withdraws bellied woodpecker, red-headed woodpecker, yellow- the larvae. The tongue is nearly twice as long as its owner's bellied sapsucker, hairy woodpecker and downy wood- head and winds around the inside back of the skull when pecker are residents. The black-backed (Arctic) and retracted. northern (American) three-toed woodpeckers have been To grip trees, a woodpecker has short, muscular legs known on rare occasions to get this far south in the win- and sharply clawed feet. On most species, two toes point ter. forward and two backward. This opposed, "yoke-toed" , The woodpecker family, Picidae fills a unique niche arrangement lets a woodpecker climb with ease. Stiff, in the food chain. Woodpeckers drill into trees to un- pointed tail feathers catch on the rough bark to brace cover insect food, to the hammering body. During molt, the two middle tail create nesting shel- feathers (the strongest ones) do not fall out until the other ters and to com- 10 have been replaced and can support the bird's weight. municate with A woodpecker's flight is undulating. The bird usually other woodpeck- launches off the side of a tree, pumps its wings four or ers. Several body five strokes, and folds them against its body. During this adaptations short pause, the bird loses a few feet of altitude. Then make this drilling more wing beats to gain altitude, another pause, and so possible. on. A wood- Woodpeckers feed mainly on wood-boring grubs, in- pecker has a sects, insect eggs and pupae. They also consume sap, nuts, sharp, stout bill and the fruits of some trees and shrubs. Hollow sounds — with a chisel-like echoes of the woodpecker's tapping — probably signal tip for chipping the location of a wood borer's channel, and the bird drills and digging into up to 100 strokes per minute to uncover the morsel. Even tree trunks and in winter they have no trouble locating insects. branches. In Most woodpeckers "drum" on resonant limbs, hollow Downy pecking out tree trunks, drainpipes, garbage can lids, tin roofs, etc. wood, the bird aims Drumming designates territory and can attract a mate.
166 Downy Common Flicker Hairy Red-headed Soft tapping may be a type of communication between lumber). Wolf trees have many limbs and cavities that mates, or between parents and offspring. provide shelter and nesting space for many species of Courtship and nesting habits are essentially alike in wildlife. all woodpeckers. Much of the rivalry between males is confined to noisy, chattering pursuit. After pair forma- Melanerpes ( Red-Headed Woodpecker tion, both sexes excavate a nest cavity in a branch or — Length, 8 - 9 inches; wingspread, 18 erythrocephalus) tree trunk. The female usually lays the white, unmarked inches. The head of an adult of this species is scarlet, and eggs directly on wood chips left in the bottom of the cav- that of a juvenile, brown. Body plumage is black and ity. Both sexes incubate, with the more aggressive male white, with a large white wing area visible when the bird often staying on the eggs overnight. Young are altricial; flies. Like the flicker, the red-headed woodpecker does a for two to three weeks they remain in the nest and are lot of feeding on the ground. It eats beetles, ants, grass- fed predigested food by their parents. In the southeast- hoppers, caterpillars and other insects, along with acorns, ern states, woodpeckers may raise two broods. corn, wild fruits and apples. Redheads store acorns in tree Woodpeckers have definite economic importance. cavities during winter and defend these food caches They do punch holes in trees, but rarely in healthy ones. against squirrels and other birds. Habitat is open forest- By stripping the bark from a dead or dying tree and clean- land, farm woodlots, towns and parks. This bird often ing up the resident wood borers or carpenter ants, they perches in the open. Nest: 8 - 80 feet up, often in an oak prevent these pests from spreading to nearby healthy and occasionally in a fencepost. Starling competition for trees. Woodpeckers also chop out homes for owls, blue- nesting sites may be reducing this species' numbers. Eggs: birds, tree swallows, nuthatches, chickadees, red and gray 4 - 7, usually five, with a 14-day incubation period. In squirrels and flying squirrels. Adversely, woodpeckers spring, the redhead is an uncommon migrant in late April sometimes damage utility and other poles. and early May; in summer, a breeding resident; in fall, an The Pennsylvania Game Commission manages state uncommon migrant from September to early November; game land woodlots and forests wih the needs of wood- and a winter resident. Call is a raucous kwrrk. peckers — and wildlife — in mind. When marking tracts scheduled for timber cutting, PGC foresters leave a pro- )— ( Sphyrapicus varius Yellow-Bellied Sapsucker portion of food-bearing trees and shrubs, as well as "wolf" Length, 7 - 8 inches; wingspread, 14 inches. Plumage var- trees (older trees, often dying, which do not make good ies within the species, but the narrow longitudinal wing
167 Black-backed Yellow-bellied Three-toed Sapsucker Pileated Red-bellied vertical white stripe down the center of its back, black stripes — visible when the bird is at rest — and the finely wings stippled with white on the upper sides, white feath- mottled back are good field marks. (The back coloration blends well with tree bark.) The belly is tinged yellow, ers forming the outer edge of the tail and white breast. Sexes are similar, but the female lacks the male's small and the head is red, black and white. Sapsuckers drill par- red patch on the back of the head. Larger size and a pro- allel rows of holes in live trees (up to 30 holes per day) portionately longer bill distinguish it from the downy and return later to drink sap and catch small insects at- woodpecker. The hairy eats beetle larvae, ants, caterpil- tracted to the sweet liquid. The bushy tongue of a sap- lars, adult beetles, spiders, etc.; also seeds and fruits. Pri- sucker effectively soaks up sap. Other foods include mary habitat is forest land and wooded swamps. Nest: 5 - beetles, ants, caterpillars, insect eggs, spiders; the cam- 30 feet up; the male may also dig a roosting cavity. Eggs: bium (layer beneath the bark) of maple, aspen, birch, fir, 3 - 6, commonly four, with a 12-day incubation period. hickory, beech, pine, oak and other trees; fruits and seeds. The hairy woodpecker is found throughout the eastern Sapsuckers inhabit forests, orchards and woodlots. US; in Pennsylvania, it is an uncommon resident in all Nest: a gourd-shaped cavity excavated 8 - 40 feet up a seasons. tree; aspen and other trees afflicted with tinder fungus are often chosen as nest sites, because the fungus creates Common Flicker a soft center that is easily dug out. Eggs: 4 - 7, usually five ) — Length, 8 - 10 Colaptes auratus ( or six, with a 12- to 13-day incubation period. The sap- inches; wingspread up to 20 inches (about the size of a blue jay). Flickers, also known as yellow hammers, have sucker is the most migratory of our woodpeckers. In spring, it is a common April migrant; in summer, a rare breeding brown backs, no white on the wings, a prominent black resident (breeds mainly across the northern US and south- band high on the breast, and bright red on the nape of the neck. The male has a black "mustache" mark extending ern Canada); in fall, a common migrant in September and from the bill back onto the throat. In flight, the white October; and in winter a rare resident, as most individu- rump patch and yellow underwings show up well. Flickers als move farther south. Call is a jay-like mewing note. are often seen on the ground or on sidewalks eating ants, Also, sapsuckers tap in a distinctive rhythm, two or three a preferred food. Their saliva neutralizes the formic acid series per minute; they do not drum. which ants contain. They also eat beetles, grasshoppers, Hairy Woodpecker ) — Length, 8 - 9 Picoides villosus ( crickets and other insects. In fall and winter, they eat poi- inches; wingspread, 15 inches. This woodpecker has a son ivy fruits, berries, corn and sumac seeds. Favored habi-
168 ity is 10 - 24 inches deep. Eggs: 3 or 4, incubated 18 days. tat is woodland, orchards, woodlots and yards. Nest: a hole These birds are uncommon residents in all seasons. They opening into a cavity, 2 - 60 feet up a tree. The cavity do not migrate but breed all over the eastern US and takes up to two weeks to build. Eggs: 3 - 10, usually 6 - 8, Canada. A pileated's powerful beak can break loose fist- with an 11- to 12-day incubation period. Starlings may size chunks of wood; the bird twists its head and beak as it drive flickers out of their newly-dug cavities. In spring, strikes to add leverage. Pileateds cut large rectangular flickers are common migrants from March to April; in sum- holes in dead trees, spars, live conifers and utility poles. mer, breeding residents (they breed east of the Rockies They drum loudly and rapidly, then more slowly, trailing and across Canada and Alaska); in fall, common Septem- wick-uh wick-uh wick-uh, in a off softly at the end. Call: ber or October migrants; and in winter, rare residents. kuk, kuk, kuk, kuk-kuk-kuk. series; also Flickers winter principally in the southern US. Call: a loud 2 -7 times per minute; also a shrill, descend- flick or flicker, )— Red-Bellied Woodpecker ( Melanerpes carolinus kee-oo. ing Length, 8 - 9 inches; wingspread, 17 inches. This wood- pecker has a "ladder back" (a pattern of black and white ( ) — Length, Dryocopus pileatus Pileated Woodpecker bands like a ladder), red cap and back of neck, and a breast 12 - 17 inches; wingspread, up to 27 inches; crow-size but tinged a very light red. The female's crown is gray, the with a long, slender neck. The largest American wood- immature's entire head is brown, and the male's crown pecker (except for the rare, if not extinct, ivorybill wood- and neck are red. Foods: acorns, beechnuts, hickory nuts, pecker). Also called the Indian hen and log cock, a grapes and corn; mulberry, poison ivy and dogwood fruits; pileated woodpecker has a solid black back and tail and beetles, wood-boring larvae and ants. Red-bellied wood- a conspicuous red crest for which it is peckers inhabit coniferous and deciduous forests, named (from the Latin word for woodlots, orchards and yards. Nest: 5 - 70 (usually less pilleus). The female cap, than 40) feet up a tree or utility pole. Eggs: 3 - 8, com- is similar to the male monly four or five, with two weeks incubation. Uncom- but does not have mon residents in all seasons, red-bellied woodpeckers red cheek patches mainly occur in the southern half of the state and along the western border. They're more common south and west of Pennsylvania. Call: a low, hoarse also a rat- chuh chuh; tling noise. Downy Woodpecker ( Picoides pubescens ) — Length, 5 - 6 inches; wingspread, 11½ inches. The downy — most common of the eastern woodpeckers — resembles a small hairy woodpecker, with a similar white back stripe and white breast. The male has a red patch on the back of his head, similar to that on the hairy. Bill length of the downy is less than the width of its head, while that of the hairy is Pileated equal to or greater than the width of its head. The downy's outer tail feathers are barred with black (in the hairy woodpecker, these are solid white). Food: wood-boring larvae, moths, beetles, ants, aphids, spiders, poison ivy and dogwood fruits, berries, corn, apples and acorns. Habitat: open forests of mixed growth, or- and has less red in the crest. Flight is strong, with irregu- chards, suburbs and parks. Nests are usually dug in rot- lar wing flapping accompanied by white flashing of wing ting wood, 3 - 50 feet above the ground and often on the undersurfaces. Foods include ants, beetles, wood-boring underside of an exposed limb. Eggs: 3 - 6, usually four or larvae and wild fruits. Pileated woodpeckers inhabit ma- five, incubated 12 days. The downy woodpecker is a com- ture coniferous and deciduous forests, valley woodlots and mon resident in all seasons. In winter, it can often be found remote mountain territory. Nest: a new hole excavated in fields with dried corn stalks, or visiting suet feeders. each year in the same nest area, 15 - 70 feet up (average Calls: a soft pik and a rattling sound. 45 feet). The entrance hole is usually oval, and the cav- Wildlife Notes are available from the Pennsylvania Game Commission Bureau of Information and Education Dept. MS, 2001 Elmerton Avenue Harrisburg, PA 17110-9797 www.pgc.state.pa.us An Equal Opportunity Employer
169 Wildlife Note — 52 Wrens LDR0103 by Chuck Fergus Wrens are small, active birds, basically brown in color, that often perch with their tails held straight up. They forage on or just above the ground in thick brush, forest understory or marsh vegetation. Wrens House belong to Family Troglodytidae, with about 70 species Wren in the New World, most of them in the tropics. Only one species lives in the Old World: the winter wren, which likely spread from Alaska to Siberia and extended its range westward until, eons in the past, it reached Britain and Iceland. Some wrens nest in cavities; others build roofed structures out of plant matter. The males of several species build "dummy" nests, preliminary nests placed in tree cavities, woodpecker holes and nest boxes, and less frequently in odd en- closed spaces such as tin cans, pockets of clothing hung outdoors, hats, boots, flower pots and drainpipes. Later, a female will choose one of the male's dummy nests, finish its construction, and lay eggs in it. Wrens often pester other birds and evict them from nest cavities, puncturing their eggs or pecking their young to death. They destroy nests in cavities and in the open; they also wreck other wrens' nests. Why such belligerence? Does an abundance of empty nests discourage predators from looking further and finding an active wren's nest? Or does killing its rivals' offspring reduce pressures on prey popu- snails. The species breeds across southern Canada and the lations, making it easier for a wren to feed its own young? United States. Individuals from the East winter mainly in Wrens eat mainly insects and spiders. A few species Georgia and Florida. will also feed on berries and seeds. Owls, small hawks Males arrive on the breeding grounds in late April or and house cats take adult wrens; raccoons, opossums, early May. They establish territories of one-half acre or larger minks, weasels, mice, squirrels, woodpeckers and snakes and advertise for females with a rich, liquid song. Males raid wrens' nests. Some wrens migrate southward in win- build dummy nests out of twigs in tree cavities, nest boxes ter, while other species remain as permanent residents or hollow fence posts; one male may construct up to seven on their breeding range. Five species are found in Penn- such nests, defending them and the space around them. sylvania. When building dummy nests, house wrens may destroy the nests and young of tree swallows, chickadees, bluebirds and Troglodytes aedon ) — The most common House Wren ( prothonotary warblers. Females either arrive later than the wren in Pennsylvania, this bird was named because it often males or stay hidden in brush until they begin inspecting lives around humans' dwellings. A house wren is five inches the males' territories. If a female finds a territory to her long and weighs a third of an ounce. Its overall color is liking, she will finish one of the male's dummy nests by gray-brown. House wrens live in open shrubby woodlands, adding a lining of grass, plant fibers, rootlets, feathers and small woodlots, woods edges, towns, suburban backyards animal hair. and city parks. They feed on insects, spiders, millipedes and In May, the female lays five to eight eggs, which are white
170 or brushy cover; they also inhabit gardens and yards. Carolina wrens forage mainly on the ground, often near downed trees or brush piles, using their curved bills to lift up leaf litter and snatch prey. They also climb up tree trunks like creepers or nuthatches. Carolina wrens catch Carolina caterpillars, chinch bugs, beetles, leafhoppers, grasshop- pers, crickets, katydids and many other insects. They eat Wren seeds of poison ivy, sumac, smartweed and other herba- ceous plants, plus fruits and acorns. Unlike the house wren, the Carolina wren is monoga- mous. Pairs often forage together and defend a territory year-round. The species has a clear, ringing song, tea-kettle, tea-kettle, tea-kettle , which it may give year- round. Carolina wrens nest in tree cavities, bird houses, crevices in stone walls, among exposed roots and in cracks or crannies in buildings. Using leaves, twigs and other plant materials, both sexes build a dome-shaped nest with a side entrance. The normal clutch is five or six eggs. Incubation is by the female and takes two weeks; the male feeds her on the nest. The young leave the nest about two weeks after hatching. Pairs usually raise two broods per year. In the last century, the Carolina wren has been ex- panding northward. Pennsylvania is on the northern edge of the species' breeding range, which extends north after mild winters and ebbs south following harsh winters. Ex- tended periods of ice and snow can devastate local popu- and speckled with reddish brown. She incubates them lations. Bewick's wren ( Thryomanes bewickii ) is a for 12 to 15 days. After the eggs hatch, the male helps similar-appearing species that bred in southern Pennsyl- with feeding the young, bringing grasshoppers, crickets, vania until around 1976; since then, it has not been found caterpillars and spiders to the growing nestlings. About nesting here. two weeks after hatching, the young leave the nest. Fe- males typically produce two broods per summer, rarely Winter Wren ( Troglodytes troglodytes ) — At just over three. A female may abandon her first brood soon after four inches in length, the winter wren is our smallest wren. the young have fledged, leaving the male to rear them; Its plumage is dark brown, and its tail is stubby. Look for she may then move to another male's territory, mate this secretive bird in deep woods, particularly hemlocks, again, and lay a second clutch. A male house wren may where it forages in brush piles and ravines — behaving mate with two or more females in his territory, although "more like a mouse than a bird," notes ornithologist Kenn he will usually help only the primary female raise her Kaufman. The male's song is a se- young. A "floater" is an unmated male who enters an es- ries of warbles and trills. Foods tablished territory and tries to drive away the resident include insects, spi- male or mate with the female. If he succeeds in taking ders, small fish over a territory, he may destroy the female's eggs or taken from young. At that point, she will usually renest. stream shallows Most house wrens leave the breeding range in Sep- and berries. In tember and early October. They migrate by night; some the East, winter are killed when they collide with communications tow- wrens breed from ers. On their southern wintering grounds, they forage in Newfoundland thick brush. The oldest house wren on record lived seven south to Georgia years, but most individuals probably survive for only a in the Appala- year or two. Ornithologists believe the species has been chians. They expanding southward since European settlement began: nest in cavi- the house wren benefits from forest fragmentation and ties, and a does well in towns and residential areas. brood of five to six young ) — The Caro- ( Carolina Wren Thryothorus ludovicianus is the norm. lina wren inhabits the eastern United States and Central Males may America. It is a permanent resident wherever it breeds. mate with At 5½ - 6 inches long, and weighing 0.7 ounces, it is the more than largest of our wrens. Carolina wrens are colorful birds one female. with rusty-brown upper plumage, a buffy or cinnamon Populations have breast and a white stripe above each eye. They prefer Winter Wren been growing in moist or bottomland woods with moderate to dense shrubby
171 ( ) — This is the typi- Cistothorus palustris Marsh Wren Pennsylvania in recent years. Winter wrens head south in cal wren of the cattail marsh. It is four and a half to five early fall, although some remain in the north and winter and a half inches long, its brown plumage marked with along streams and in swamps. black and white stripes on the back and a white eye-stripe. ) — This small (four Cistothorus platensis ( Sedge Wren Marsh wrens arrive on the and a half inches), shy wren inhabits moist upland sedge breeding range in late April meadows with little or no standing water. It was formerly Marsh or early May. The male's known as the short-billed marsh wren. Sedge wrens often Wren song is reedy and gur- breed in small colonies; Hal Harrison once counted 35 to gling, lasts one to 40 singing males on a 10-acre site. They may occupy a two seconds, and suitable habitat for several years, then disappear. Males is given up to 20 sing a dry, rattling song. The actual nest is a ball of dried times per minute, or green sedges woven into growing vegetation two to by day and at three feet above the ground. The usual clutch is seven times by night. eggs. A female generally produces two broods per year, Not particularly and males may mate with more than one female. Surveys musical, it re- have shown that the sedge wren is rare and declining in minded one is listed as a threat- Cistothorus platensis the Northeast. naturalist of ened species in Pennsylvania. "air-bubbles forc- ing their way through mud or boggy ground when trod upon." Sedge Wren The marsh wren forages on the marsh floor, flitting up and cling- ing to stalks and leaves of cattails, bulrushes and other plants while searching for prey. It takes aquatic insects and their larvae, other insects, spiders and snails; often it nabs larvae from the surface of the water. Both males and females will peck and destroy the eggs of other birds in their territory; red-winged blackbirds often at- tack marsh wrens on sight. Males typically build dummy nests — around six for each breeding nest used by a fe- male. The female weaves an oblong nest out of cattails, reeds and grasses, secured to standing vegetation. A short tunnel leads to a central cavity in which three to six eggs are laid. The female incubates the clutch for about two weeks. Fed by both parents, the young fledge after 12 to 16 days; the adults care for them for another two weeks. Two broods are produced each year. Male marsh wrens are polygymous: up to half of all breeding males may each mate with two or more females. Marsh wrens in the East winter along the Atlantic and Gulf coasts.
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redpajama_set_name: RedPajamaCommonCrawl