



Produced by Larry B. Harrison, Josephine Paolucci and the
Online Distributed Proofreading Team at http://www.pgdp.net.








UNITED STATES DEPARTMENT OF AGRICULTURE

FARMERS' BULLETIN

WASHINGTON, D. C. 702 JANUARY 17, 1916

Contribution from the Bureau of Biological Survey, Henry W. Henshaw,
Chief.

COTTONTAIL RABBITS IN RELATION TO TREES AND FARM CROPS.

By D. E. LANTZ, _Assistant Biologist_.

[Transcriber's Note: Words surrounded by tildes, like ~this~ signifies
words in bold. Words surrounded by underscores, like _this_, signifies
words in italics.]




CONTENTS.


                                   Page.

Introduction                           1

Habits of cottontail rabbits           2

Protection of rabbits                  3

Means of repressing rabbits            5
    Natural enemies                    5
    Hunting                            6
    Trapping                           6
    Poisoning                          9
    Bacterial diseases                10

Protection of crops from rabbits      10
    Rabbit-proof fences               10

Tree protection                       10
    Washes                            10
    Mechanical contrivances           11
    Other means                       12


NOTE.--This bulletin discusses the distribution and habits of cottontail
rabbits and methods of controlling their ravages on trees and cultivated
crops by means of trapping, poisoning, and supplying safeguards. For
general distribution.




INTRODUCTION.


Among the serious pests in orchards and tree plantations are the several
native species of rabbits. These animals do considerable damage to
garden truck and other farm crops also, especially on lands recently
opened to cultivation. North American rabbits belong to two general
classes easily distinguished by their size and habits.

The larger forms[1] include the arctic and varying hares, or snowshoe
rabbits, and the jack rabbits, and are found throughout nearly all of
Alaska and Canada and in all the States west of the Mississippi except
Arkansas and Louisiana. East of the Mississippi they inhabit the
northern parts of Minnesota, Wisconsin, and Michigan, most of New York
and New England, and southward in the Appalachian Mountains, parts of
Pennsylvania, Maryland, and Virginia.

[Footnote 1: Genus _Lepus_.]

The smaller forms,[2] generally called "cottontail rabbits," occur in
every State, but are absent from the greater part of Maine, the
northern parts of New Hampshire, Vermont, New York, Michigan, Wisconsin,
and Minnesota, and from the western parts of Washington and Oregon. In
recent years they have extended their range northward in the New England
States, New York, and portions of the West, and have invaded and
occupied a considerable part of the Province of Ontario. In habits they
differ materially from the larger rabbits. They live in copses and
thickets more than in open fields. The young are born blind, naked, and
helpless, while those of the larger rabbits have the eyes open, are
partially furred, and active when born.

[Footnote 2: Genus _Sylvilagus_.]

Rabbits of both genera, however, feed exclusively on vegetation, and are
at times harmful to crops and especially to trees. Because of their size
and great abundance in parts of their range, jack rabbits are by far the
most destructive, but, except in a few places where they have been
introduced, none are found east of the Mississippi. Epizootics (diseases
which attack many animals at the same time) are an effectual natural
check, and after such attack occurs, jack rabbits are usually so reduced
in numbers that they are not troublesome again for several years.

Traps and other devices that are effective with cottontail rabbits do
not always succeed with jack rabbits. The recommendations contained in
this bulletin will, therefore, apply only to cottontail rabbits, but
they may suggest methods that, with modifications, may be used against
the larger forms.




HABITS OF COTTONTAIL RABBITS.


Cottontail rabbits (fig. 1) are so well known that little need be said
of their habits. They breed several times each year during the warmer
months, the litters averaging five or six young. The nest is usually
placed in a hollow or depression of the ground, often in open fields or
meadows. It is composed of dead grass and warmly lined with fur which
the female pulls from her own body. The male rabbit takes no part in
caring for the young, and the female weans them as soon as they are able
to leave the nest. These animals breed so rapidly that in spite of many
natural enemies, and of the fact that they are hunted for human food,
they often become numerous enough to inflict serious losses on farmers
and fruit growers in many parts of the United States (fig. 2).

Cottontail rabbits eat all sorts of herbage--leaves, stems, flowers, and
seeds of herbaceous plants and grasses--and leaves, buds, bark, and
fruits of woody plants or trees. They usually prefer the most succulent
foods, as young shoots, tender garden vegetables, clover, alfalfa, and
fallen ripe fruits; but they exhibit also a remarkable delicacy of
taste in their selection of certain varieties of cultivated plants and
in their neglect of others of the same species. Prof. C. V. Piper
reports that in Oregon rabbits ate Arabian alfalfa down to the ground,
while they did little or no damage to other varieties grown in
surrounding plats. Prof. C. A. Mooers, of the Tennessee Agricultural
Experiment Station, reports similar observations in regard to their
taste for soy beans, stating that they greatly relish the mammoth yellow
variety and that it is practically the only one that suffers from their
depredations. When favorite foods are absent rabbits resort to whatever
is available. It is during summer droughts or when deep snows cut off
ordinary supplies that the animals attack the bark of growing trees or
shrubs.

[Illustration Fig. 1.--Cottontail rabbit in its "form."]


PROTECTION OF RABBITS.

Cottontail rabbits are valuable for food and afford excellent sport for
gunners. In many States, especially east of the Mississippi River, they
are protected as game. In fruit-growing and truck-farming districts
farmers regard them with disfavor, and there is considerable rivalry
between sportsmen and farmers to have their opposing views reflected in
game laws. The interests of the two classes do not seriously differ,
however, for when rabbits are closely hunted losses from their
depredations are usually reduced to a minimum. Still there is danger
that in years favorable for their increase the animals may inflict
serious injury to trees during severe winters.

Rabbits are protected (1915) by close seasons in States and Provinces as
shown in Table I. Twenty-eight States, Alaska, and the Canadian
Provinces not mentioned in the table do not protect rabbits of any kind.
In the District of Columbia all shooting is prohibited except on certain
river marshes. In Kentucky rabbits may be taken with dog, trap, or snare
at any time, and the close season for shooting is evidently solely for
the purpose of keeping gunners out of fields and woods during the two
months immediately preceding the open season for quails. In Wisconsin 46
counties, mostly in the southern half of the State, have no close season
for rabbits. In California only cottontails, or bush rabbits, are
protected.

[Illustration Fig. 2.--Apple tree killed by rabbits.]

TABLE I.--_Lengths of open season for rabbits or hares._

----------------------+-----------+-----------+---------
                      | Beginning | Beginning | Length
State or Province.    | of        | of        | of open
                      | open      | close     | season.
                      | season.   | season.   |
----------------------+-----------+-----------+---------
                      |           |           | _Months._
Maine                 | Oct. 1    | Apr. 1    |  6
New Hampshire         | do.       | Mar. 1    |  5
Vermont               | Sept. 15  | do.       |  5-1/2
Massachusetts         | Oct. 12   | do.       |  4-3/5
Rhode Island          | Nov. 1    | Jan. 1    |  2
Connecticut           | Oct. 8    | do.       |  2-3/4
New York              | Oct. 1    | Feb. 1    |  4
  Long Island         | Nov. 1    | Jan. 1    |  2
New Jersey            | Nov. 10   | Dec. 16   |  1-1/5
Pennsylvania          | Nov. 1    | Dec. 1    |  1
Delaware              | Nov. 15   | Jan. 1    |  1-1/2
Maryland              | Nov. 10   | Dec. 25   |  1-1/2
District of Columbia  | Nov. 1    | Feb. 1    |  3
Virginia              | do.       | do.       |  3
Kentucky              | Nov. 15   | Sept. 15  | 10
Ohio                  | do.       | Dec. 5    |  2/3
Indiana               | Apr. 1    | Jan. 10   |  9-1/3
Illinois              | Aug. 31   | Feb. 1    |  5-1/30
Michigan              | Oct. 1    | Mar. 2    |  5-1/30
Wisconsin:            |           |           |
  6 counties          | Sept. 10  | Feb. 1    |  4-2/3
  13 counties         | Oct. 10   | do.       |  3-2/3
  6 counties          | Nov. 1    | Jan. 1    |  2
Colorado              | Oct. 1    | Mar. 1    |  5
California            | July 31   | Feb. 1    |  6-1/30
British Columbia      | Sept. 1   | Jan. 1    |  4
Ontario               | Oct. 1    | Dec. 16   |  2-1/2
Quebec:               |           |           |
  Zone 1              | Oct. 15   | Feb. 1    |  3-1/2
  Zone 2              | do.       | Mar. 1    |  4-1/2
Newfoundland          | Sept. 20  | Jan. 1    |  3-1/3
Prince Edward Island  | Nov. 1    | Feb. 1    |  3
Nova Scotia           | Oct. 1    | Mar. 1    |  5
----------------------+-----------+-----------+---------

In about half the States that have a close season for rabbits the laws
permit farmers and fruit growers to destroy the animals to protect crops
or trees. Such provision might well be incorporated in game laws of all
States. For lack of it farmers have sometimes suffered severe losses,
and not a few have been compelled to pay fines for trying to protect
their property from rabbits. In States that protect rabbits it is well
for the farmer to be acquainted with the game laws and in case of doubt
to have a clear understanding with local and State game, wardens before
undertaking to destroy rabbits.




MEANS OF REPRESSING RABBITS.


NATURAL ENEMIES.

Among the agencies that help to keep down the numbers of rabbits few are
more effective than carnivorous birds and mammals. These include large
hawks and owls, eagles, coyotes, wildcats, foxes, minks, weasels, dogs,
and cats. Eagles, the larger species of hawks, and all the large and
medium-sized owls make rabbits a great part of their food. From the
standpoint of the farmer and fruit grower these birds and certain
carnivorous mammals are far more beneficial than harmful. On the other
hand, poultry growers and sportsmen regard them as enemies to be
destroyed whenever possible. In the absence of such natural enemies,
rabbits, as well as rats and mice, often become a menace to valuable
crops. Indiscriminate slaughter of carnivorous birds and mammals should
be suppressed whenever rodent pests are to be controlled.


HUNTING.

Hunting has been the most important factor in keeping down the numbers
of rabbits in America. In some parts of the country the animals have
been so reduced in numbers by shooting that sportsmen have invoked
legislation to prevent their extermination. Shooting is undoubtedly the
best method for hunting this animal. Ferreting is often impracticable,
since our native rabbits do not habitually burrow; besides, the use of
ferrets