Hanna Kahl
Bugs=$$$
On December 26, 2014 By hannamariakahlIn UncategorizedLeave a comment
According to a 2006 article by Losey and Vaughan, the services wild insects freely provide are worth at least 57 billion dollars annually.
These estimates are based on the services insects provide in:
1) Dung Burial: 0.38 billion/year
Several "dung beetles" from the superfamily Scarabaeoidea make a valuable resource out of our waste.
Picture from: http://simple.wikipedia.org/wiki/Dung_beetle
Picture from: http://blogs.scientificamerican.com/guest-blog/2012/08/27/the-hidden-truths-about-calories/
2) Pollination: $3.07 billion/year
Not only managed bees such as Apis mellifera (the western honey bees) pollinate important crops but wild bees also pollinate wild and domesticated flowers, helping to provide us with blueberries and apples.
Normia melanderi (the Alkali) visiting alfalfa
From: http://www.honeybeesuite.com/alkali-bees-the-alfalfa-specialists/
According to the USGS, native bees are estimated to pollinate up to 80% of the flowering plants in the world (http://www.usgs.gov/blogs/features/usgs_top_story/the-buzz-on-native-bees/)
Bumble bees (Bombus) are effective at pollinating tomato flowers, like the one pictured below.
From: http://pollinator.com/gallery/tomatbbee2018w.jpg
3) Pest control: 4.49 billion/year
Insects also defend our gardens and farms from pests that, if unchecked, could munch our crops away.
A ladybug (Coccinillidae) feasting on an aphid, an insect that sucks the sap out of a wide variety of plants.
From: http://www.cirrusimage.com/Beetles/seven-spotted_ladybug_77.JPG
Alligator weed flea beetles (Agasicles hygrophila) keeping alligator weed, an invasive weed in most southern states of the USA, at bay.
4) Recreation: $49.96 billion/year
Hunting small mammals, bird-watching, and fishing are all popular hobbies. Many of these animals that are the object of these hobbies depend on insects for food. If insect populations, these birds, small mammals, and fish would most likely suffer along with them.
A trout preparing to swallow down a mayfly treat.
From: http://thefisheriesblog.com/2013/09/30/the-other-side-of-fall-leaves/
A favorite bird for bird-watchers the charismatic scarlet tanager (Piranga olivacea) is clutching a meal. They are primarily insectivores.
From: http://www.gregmillerbirding.com/tag/ohio/
Not only are insects awesome in and of themselves, it is clear they have clear monetary value that many do not think of when looking at them crawling or flying about.
Tattered P. picta
On June 26, 2014 By hannamariakahlIn UncategorizedLeave a comment
This butterfly is P. picta (the Painted Crescent). Its ragged wings have little tears at the fringe, its colors are starting to wane, and its appearance and its name brings to mind a painting with chipping paint.
But still its a beautiful butterfly that perched long enough for me to get a picture before it flitted away.
The Nest Impostors
On April 18, 2014 By hannamariakahlIn Uncategorized, Wildlife IDLeave a comment
Two pink vireo eggs on top of three brown speckled cowbird eggs.
Sitting seemingly innocent in a nest created by a hard-working mom-not their mom- there are three brown speckled eggs, unaware so far of their role as impostors and strangers in a home that is not theirs.
While, two tiny pink eggs sit unaware of their oncoming struggles against the injustice of parasitizing siblings or their impending abandonment. Yes, perhaps the mom of the tiny pinks, a Bell's Vireo (Vireo bellii), in an anxious frenzy, has already left the tiny pinks all alone to compete with the three unplanned brown speckleds without her help. (I'm not sure if the nest is a Bell's Vireo's nest, although it does seem to be made by some kind of vireo at least).
If the Bell's Vireo has decided to stay, then she will have a hellish time raising five children, three of which are not even her own.
The brown speckled eggs are (maybe) the eggs of a Brown-headed Cowbird (Molothrus), an infamous invader with the ability to loot by giving their children to others.
Cowbirds are friends with cows (hence, the name). The cowbirds prance up and down gobbling up the stream of insects that the cows stir up as they walk through the pasture. Cowbirds watch empty nests, In this instance, there was a cowbird eyeing a Bell's Vireo's meticulously built nest. Plotting its espionage, it bided its time until the Bell's Vireo left. Then it planted its larger eggs in the nest and left its offspring to the flip-of-a-coin (with the chances bent towards abandonment) of a Bell's Vireo mother. Though sometimes, the Cowbird mother will return to see how her eggs are faring in their foster home. Sometimes on its return visit, if its young has already hatched, it may push out the other eggs of the nest leaving a bereaved Bell's Vireo mother with no young except those that are not her own.
Cowbirds (male in front; female behind)
Although Cowbirds may not be the best bird mothers, they are incredibly fecund. They are occasionally able to produce thirty-six eggs during one summer mating season, so they can afford to take a gamble and put their eggs where (according to their unwilling hosts) they do not belong in the hope that the host of the nest will take care of their eggs instead of them. One may be tempted to call them lazy mothers, but it is actually that they invest a lot of energy in reproduction.
Cowbirds are so much of a threat to the host of the nest that they parasitize that they are cited as one reason why the Black-caped Vireo is now listed as endangered. Individual cowbirds can even act as specialized nest infiltrators, targeting the nests of a specific species of birds. This Cowbird could have been targeting Vireo nests.
Bell's Vireo
If the young cowbird eggs pictured do hatch, then the Cowbird hatchlings will quickly learn the pesky ways of their biological parents. They will hatch fast, complain for food, grow fast, and bully and steal attention from the Vireo hatchlings sometimes even killing their foster brothers and sisters.
However, the host of the parasitic eggs, Bell's Vireos or over 219 other host species, do not sit back passively when Cowbirds invade. If they catch the female Cowbirds laying the eggs, the female and male Vireos will sometimes attack. They often retaliate by building a nest on top of the Cowbird eggs or poking them or moving them out of the nest. Tactics of fighting back against cowbirds differ depending on the size of the victim. Still Cowbirds remain relatively successful in their sneaky egg-laying way.
In sum, it would be tough to be a bird with the eggs of impostors in your nest.
"Brown-headed Cowbird" , The Cornell Lab of Ornithology, http://www.allaboutbirds.org/guide/brown-headed_cowbird/id
Bryan L Sharp and Barbara E. Kus, 2004. "Sunrise Nest Attendance and Aggression by Least Bell's Vireos Fail to Deter Cowbird Parasitism". Wilson Bulletin, 116(1) pp. 17-22.
Slithering She-males
On February 28, 2014 By hannamariakahlIn UncategorizedLeave a comment
Thamnophis sirtalis parietalis encountered in Manhattan, Kansas
Garter snakes are masters of disguise. Not only can they blend into the grass so well that I could not see this garter snake until my foot was hovering right above it paused only due to a flash of rosy hue I saw last minute beneath my foot, but males can also fake being female.
Meet Thamnophis sirtalis parietalis (the red-sided garter snake).
Snakes heavily depend on their tongues to sort of "smell" their chemical environments. They flicker their tongue out to receive chemical cues from their cues and then pass the chemical cues over an organ called the Jacobson's organ. It seems that humans have this organ as well.
With humans it is debated whether this organ is non-functional (link to article leaning towards this) or if it can be a kind of "Sixth Sense" (link to article suggesting this). Very recent articles have suggested at least some endocrine activity associated with this organ (link).
However with snakes the activity of the Jacobson's organ is highly documented. In fact snakes highly depend on this system called the vomeronasal system to sense predators, catch prey, and for mating. This system helps them respond rapidly to pressing necessities.
In mating, the vomeronasal system help garter snakes detect whether another garter snake is a potential mate or a competitor. They are able to distinguish this information based on pheromones, a secreted or excreted chemical particle that triggers a social often sexual response in other individuals. Females emit a certain pheromone blend. Male garter snakes literally stick their tongues out repeatedly and look for the "taste" of the best "smelling" female (with the strongest pheromone signal) to mate with. Read more about this here.
Some male garter snakes, particularly males of the red-sided garter snake, have learned to take advantage of the vomeronasal system to manipulate others and get a head start in terms of hooking up with the females. These sneaky males have the capability to mimic the pheromone signal of a female during breeding season to trick other males into going after it.
These males, temporarily called false females, trick and round up all the male competitors. Males flock around them desperate to breed (thinking with their….tongue? that the false females are actually females) and get confused about the technical difficulties of mating with the false females. The false females rapidly stop emitting the female pheromone signal turning back into their real trickster male pheromone status. Since snakes are cold-blooded, they need sufficiently warm temperatures to have the energy to move fast. Warmed from the sexually frustrated males mobbing it, the trickster male has the warmth necessary to make a bolt at the actual females while the other clueless males are left behind.
In result, males able to emit the pseudo female pheromone blend were able to have higher mating success, then males that did not emit the pseudo female pheromone blend. How do males do this? A new study suggests that estrogen allows male red-sided garter snakes to emit female type pheromones. Here is the link to the study.
Imagine. This is like a man dressed persuasively like a sexy woman going to the bar and getting the complete attention of all the horny dudes, and at the same time getting close to all the attractive women in the bar. Then smoothly and swiftly revealing to the hottest woman in there that she is actually a he and is available. Crazy!
***Note: The red-sided garter snake actually only seems to depict this deceptive behavior in cold areas at the northern fringe of their habitat, such as Canada, not in Kansas where I saw this snake, and I'm not sure if this garter snake is a male or female. I'm not 100% sure that it is a red-sided garter snake but I think it is.
Byssus or Delaware Skipper?
On February 21, 2014 By hannamariakahlIn Uncategorized, Wildlife IDLeave a comment
I'm trying to identify a skipper found in Manhattan, Kansas. Problem is that online there is conflicting images saying that this little guy is either this butterfly or that.
Anyways, what I do know is skippers are tiny, pretty but nearly unnoticeable bugs. Many skippers feed on grasses as larvae and nectar as adults. They are very prevalent on the prairies and have a very funnily bouncy way of flying. Many skippers, especially this skipper, remind me of tabby cats. They are big-eyed, furry, and like to bask in the sun.
After spending nearly 2 hours on identifying this little guy and having encountered this issue countless time before, I've come to a conclusion that there needs to be more development of online resources for insect ID.
Hmmm….perhaps I will make online insect ID development a project of mine further down the road, but in the mean time it seems that I have to buy more insect ID books and communicate with others interested in insect ID.
What do you think this insect is? Have you ever seen this one?
I have limited it down to probably being either a Delaware Skipper (Anatrytone logan) or a Byssus Skipper (Problema byssus) and I am leaning towards calling it a Delaware Skipper. Both are commonly found in prairies, which is where I found this skipper. The black bar at the end of the forewing seems to match more with the Delaware Skipper.
The images of Byssus Skippers range from being mostly black in color (like the Wikipedia page written on Byssus Skippers) to more bright and orange in color (like the skipper featured in my photo). Also, I found it in Kansas and the Byssus seems to be more prevalent in Kansas so that confuses matters. Through looking at discussions and Google images it seems that others have expressed this confusion as well.
A Green Iguana Encounter
On February 6, 2014 By hannamariakahlIn UncategorizedLeave a comment
While doing a survey of plant species in the area on the study site, my partner for the day, a PhD student studying mistletoe, noticed Dendropemon caribaeus (mistletoe common in the Caribbeans) growing on Citherexylum spinosum (a tree shrub I am sure to talk about more later and a common host for Dendropemon). Mistletoe obtains part of it's nutritional requirement from its host, in this case the Citherexylum. So there was no surprise yet.
Upon nearing closer to the Dendropemon clump, we noticed what looked to be a dead stick sticking out from below the Dendropemon. My partner almost took a tug at the "stick". Yet, he nearly jumped in surprise because he suddenly realized that above the "stick" was a shiny green blinking eye, and the "stick" was attached to an iguana.
Do you see the tail?
We realized we had come face to face with the common miniature dragon, known as the green iguana or Iguana iguana. I'd come face to face with these common reptiles before but I had never realized how pretty its eyes are.
peekaboo! I see you!
Searching "iguana eyes" on Google images now reveals that I'm not the only one. But extensive searches on green iguanas seem to suggest a more malicious side of the tale of the green iguana.
Green iguanas are thought of as invasive pests here in Puerto Rico, as well as in many other parts of the world. They are said to sometimes eat native plants, invertebrates, and bird eggs which may put some of these populations at risk. It does seem that iguanas sometimes stray too close to neighborhoods for the liking of many. They run away from people usually and are not confrontational but seem scary to some while they are around because of their size, claws, and teeth. They are often described as a "nuisance" and "invasive threat." The government here in Puerto Rico has responded to this "threat" by encouraging the killing and exporting of iguanas to countries in South America where people eat it as a specialty.
However, in contradiction, the green iguana is protected by Convention on International Trade in Endangered Species (CITES), the research demonstrating that iguanas are an all-around nuisance is lacking/flawed, and in my personal experience they aren't as aggressive to humans as many want to point them out as. Furthermore, green iguanas disperse seeds, potentially promoting plants that they prey on and are said to threaten. Several birds of prey supplement their diets with the meaty lizard. Although, their population is said to be growing out of control, like many other reptiles they compete with each other making sure to self-contain their population at least to some extent. My supervisor has written articles on the exaggeration and fiction surrounding the potentially negative aspects of the green iguana.
In sum: There is a great necessity for caution. Thought and research must be done thoroughly before terms like "invasive threat" are used and are thrown around as slurs, making it difficult for people to objectively and scientifically evaluate the ecosystem effects of an animal. Green iguanas may actually be a threat to something or they may actually be quite harmless, but more research must be done especially on the diet of the green iguana….
And I think green iguana eyes (at least) are beautiful.
What do you think about this? What does evidence or your observations suggest to you?
Mist Netting with a Tough Dead Bird
On January 10, 2014 By hannamariakahlIn Field Methods, Personal, UncategorizedLeave a comment
We had a name for him, but now I don't remember what his name was. I have no clue why that smelly, beat-up, mangy, dead creature comes to my mind now or why it's blank empty eyes still haunt me.
Although coming to think of it, he was our unsung hero, a warrior, a martyr for science. When trying to think of his name, I want to call him "Rocky" because he knew how to take a hit, and I'm sure when he was alive he was fierce.
He was a decoy.
Manhattan, Kansas, Spring 2010. It's one of those sticky days again, but I don't seem to mind. I'm a field technician for a Research Experience for Undergraduates program. My first Ecology experience. I'm giddy like a kid the day after Halloween. I'm starting to realize that Ecology is my field.
Konza Prairie
We are out on Konza Prairie, a biological station, with miles and miles of wavelike weeds.
We (my research mates, a tight-knit team of 3 and my thesis adviser) are mist-netting, drawing a transparent net against the horizon and waiting like spiders to pounce, except not on insects but on birds (though, I acknowledge that some of my favorite spiders can catch birds…future post?…).
dickcissel
We are waiting for a bird, a dickcissel (Spiza americana), tiny, yellow eye-shadowed, yellow-bellied (literally) tart that sings simple insistent songs all day.
(Yes, now you can laugh at the word dickcissel. Get it out of your system. Because I'm going to be talking about dickcissels all blog post long, and I've heard it all. Make all the penis jokes you'd like. In fact I might later write about all the unintentional conversation I had about penises throughout this research experience. Preview: Isn't this dick weird? Its science I swear. We'll talk about it later. Also, I have noticed the species name sounds like an STD, but I didn't name it.)
Dickcissels were named for their songs which in brief sound like dick and cissel (creative right?) occasionally with a trill.
Here is where Stinker, the dead bird, comes in. Yes, one of my field partners, just confirmed that was his name. Stinker was a dickcissel before his unfortunate death and partial resurrection as a surrogate. And well now, being the handy dandy dead bird he is, we use him to help lure in alive dickcissels.
When we identify birds without a band on their ankle showing the numbers of their "ID card" so to speak, we prepare to band them with a unique number-coded (possibly quite fashionable) anklet so that we can later distinguish individuals, as well as other select factors about the individuals, such as, in our case: wing span, estimated age, and weight. We also take pictures to remember the little dicks by.
Out on the tallest shrub he can find we see a prideful male dickcissel singing his heart out to all the available hunnies and at the same time trying to broadcast the ultimate machismo attitude. He alternates between "how you doin'?" and "you don't wanna mess with me!" We know he's a male because with this species only males sing so loud and cocky. He's a perfect catch, not only probably for all of the females, but also for us. We are set to capture.
So first we set up the mist nets. We draw out the net taut between two poles. We make sure that the poles are partially hidden in bushes if possible and the net is partially disguised by some tall grass. To learn more about mist netting click here. (This is by Point Blue Conservation Science. Watch after the 1 minute mark to see mist netting).
Then we bring Stinker out of his Triscuit box in which he is kept. He is in dire need of upkeep already, feathers falling off, patches missing, gaunt, and then we tie the wiring sticking out of him to a stake. He doesn't even complain. Stinker is such a good sport! It may help that he can't feel it, but still not even many dead creatures can brag about being stuck to a stake every day. The stake with Stinker "perched" on top stands in front of the net.
Then we press play on our boombox, which blasts out a song of a foreign dickcissel in the territory of our target. That gets our target pretty pissed, and being the manly man he is he comes over to show this fictional dickcissel who the boss is, and who does he see? He sees Stinker perched, with what he probably imagines as a smirk or in bird terms a "fuck you" kind of look.
Now our target dickcissel is not going to take that. No way. He goes after Stinker who he mistakes as an arrogant alive sod (these birds are often irrational in their anger). Our target dickcissel takes a few swings, swooping in a downward flight and clipping at Stinker with his beak probably taking some chunks out of our stiff, but Stinker stands his ground. We slowly creep closer and closer to the target with the time Stinker buys us. The target dickcissel takes another few swings, and Stinker is in really sick shape, feathers and chunks flying everywhere, struggling to stay on the pole, but then the target dickcissel makes a false move and veers too close to the net in what may have been the final attempt to finish his pretend offender.
That's when we give each other knowing looks and run out from our spots that we were watching the fight from rushing our target. Flustered, the unsuspecting bird flies straight into the net. We untangle him, record data on him, band him to ID him later, and then release him.
We appear unblemished from this engagement but Stinker is in a pathetic state. His insides gush out.
Stinker amazingly lasts the month long season. Fight after fight he got the rest of the living fluff beat out of him, but he continued playing his defiant role better than any I've known. We had to stitch him up multiple times and give him a few make overs but nothing drastic.
Yet, despite the service Stinker played for us, at the end of the bird banding month, instead of giving him a trophy or finding him a fetching mate, we threw him in the freezer, and forgot about him. We busied ourselves in our research, finished writing abstracts and giving presentations. We almost left him in their forever but we suddenly remembered Stinker the day before leaving. We brought him out of the freezer and decided to give our freezer-burned old buddy a more proper ending.
We drove to the prairie at night in our jeep, some of us had a few drinks, and we had a right proper funeral for the war veteran. We said many fine things. "Stinker you were always there for us." "You were our hero." "You are a champ." Then, we left him to rest in peace for what we hoped to be the final time.
Dedicated to Stinker.
This is my favorite dead bird experience. Have you ever seen a dead bird? What was that like for you?
University of California-Davis,
Department of Entomology, Briggs Hall,
550, Storer Mall, Davis, CA 95616
Email: hkahl@ucdavis.edu