Jackrabbits and Hares
General Jackrabit and other Hares Facts
Identification
Three major species of jackrabbits
occur in North America. These
hares are of the genus Lepus and are
represented primarily by the blacktail
jackrabbit, the whitetail jackrabbit, and
the snowshoe hare. Other members of
this genus include the antelope jackrabbit
and the European hare. Hares
have large, long ears, long legs, and a
larger body size than rabbits.
The whitetail jackrabbit is the largest
hare in the Great Plains, having a head
and body length of 18 to 22 inches (46
to 56 cm) and weighing 5 to 10 pounds
(2.2 to 4.5 kg). It is brownish gray in
summer and white or pale gray in
winter. The entire tail is white. The
blacktail jackrabbit, somewhat smaller
than its northern cousin, weighs only 3
to 7 pounds (1.3 to 3.1 kg) and is 17 to
21 inches (43 to 53 cm) long. It has a
grayish-brown body, large blacktipped
ears, and a black streak on the
top of its tail. The snowshoe hare is 13
to 18 inches (33 to 46 cm) long and
weighs 2 to 4 pounds (0.9 to 1.8 kg). It
has larger feet than the whitetail and
blacktail jackrabbits. The snowshoe
turns white in winter and is a dark
brown during the summer. Its ears are
smaller than those of the other hares.
The antelope jackrabbit is 19 to 21
inches (48 to 53 cm) long and weighs 6
to 13 pounds (2.7 to 5.9 kg). Its ears are
extremely large and its sides are a pale
white. The European hare is the largest
of the hares in the Northeast, weighing
7 to 10 pounds (3.1 to 4.5 kg) and
reaching 25 to 27 inches (63 to 68 cm)
Where food and shelter are available
in one place, no major daily movement
of hares occurs. When food areas and
shelter areas are separated, morning
and evening movements may be
observed. Daily movements of 1 to 2
miles (1.6 to 3.2 km) each way are
fairly common. In dry seasons, 10-mile
(16-km) round trips from desert to
alfalfa fields have been reported.
Damage
Hares consume 1/2 to 1 pound (1.1 to
2.2 kg) of green vegetation each day.
Significant damage occurs when hare
concentrations are attracted to
orchards, gardens, ornamentals, or
other agricultural crops. High jackrabbit
populations can also damage
range vegetation.
Most damage to gardens, landscapes,
or agricultural crops occurs in areas
adjacent to swamps or rangeland normally
used by hares. Damage may be
temporary and usually occurs when
natural vegetation is dry. Green vegetation
may be severely damaged during
these dry periods.
Orchards and ornamental trees and
shrubs are usually damaged by
overbrowsing, girdling, and stripping
of bark, especially by snowshoe hares.
This type of damage is most common
during winter in northern areas.
Rangeland overbrowsing and overgrazing
can occur any time jackrabbit
numbers are high. Eight jackrabbits are
estimated to eat as much as one sheep,
and 41 jackrabbits as much as one cow.
in size. This nonnative hare is brownish
gray year-round.
Range
The whitetail jackrabbit is found
mainly in the north central and northwestern
United States and no further
south than the extreme north central
part of New Mexico and southern
Kansas.The blacktail jackrabbit
is found mainly in the southwestern
United States and the
southern Great Plains, and no further
north than central South Dakota and
southern Washington. Snowshoe
hares occupy the northern
regions of North America, including
Canada, Alaska, the northern continental
United States, and the higher
elevations as far south as New Mexico. Antelope jackrabbits are
found only in southern Arizona, New
Mexico, and western Mexico. The
European hare is found only in southern
Quebec, New York, and other
New England states.
General Biology,
Reproduction, and
Behavior
Members of the genus Lepus are born
well-furred and able to move about.
Little or no nest is prepared, although
the young are kept hidden for 3 to 4
days. Females may produce up to 4
litters per year with 2 to 8 young per
litter. Reproductive rates may vary
from year to year depending on
environmental conditions.
Estimates of jackrabbit populations
run as high as 400 jackrabbits per
square mile (154/km2) extending over
several hundred square miles. Range
damage can be severe in such situations,
especially where vegetation productivity
is low.
Legal Status
Jackrabbits are considered nongame
animals in most states and are not
protected by state game laws. A few
states protect jackrabbits through
regulations. Most states in which
snowshoe hares occur have some
regulations protecting them. Consult
local wildlife agencies to determine the
legal status of the species before applying
controls.
Damage Prevention and
Control Methods
Exclusion
Fencing. Exclusion is most often
accomplished by the construction of
fences and gates around the area to be
protected. Woven wire or poultry netting
should exclude all hares from the
area to be protected. To be effective,
use wire mesh of less than 1 1/2 inches
(3.8 cm), 30 to 36 inches (76 to 91 cm)
high, with at least the bottom 6 inches
(15 cm) buried below ground level.
Regular poultry netting made of 20-
gauge wire can provide protection for
5 to 7 years or more. Although the initial
cost of fences appears high—about
$1,000 per mile ($625/km)—they are
economically feasible for protecting
high-value crops and provide yearround
protection on farms with a history
of jackrabbit problems. Remember
to spread the initial cost over the
expected life of the fence when comparing
fencing with other methods.
Exclusion by fencing is desirable for
small areas of high-value crops such as
gardens, but is usually impractical and
too expensive for larger acreages of
farmland.
Electric fencing has been found to
exclude jackrabbits. Six strands spaced
3 inches (7.6 cm) apart alternating hot
and ground wires should provide a
deterrent to most hares. Modern energizers
and high-tensile wire will minimize
cost and maximize effectiveness.
Tree Trunk Guards. The use of individual
protectors to guard the trunks
of young trees or vines may also be
considered a form of exclusion.
Among the best of these are cylinders
made from woven wire netting.
Twelve- to 18-inch-wide (30.5- to 45.7-
cm) strips of 1-inch (2.5-cm) mesh
poultry netting can be formed into cylinders
around trees. Cylinders should
be anchored with lath or steel rods and
braced away from the trunk to prevent
rabbits from pressing them against the
trees and gnawing through them.
Types of tree protectors commercially
available include aluminum, nylon
mesh wrapping, and treated jute cardboard.
Aluminum foil, or even ordinary
sacking, has been wrapped and
tied around trees with effective results.
Wrapping the bases of haystacks with
3-foot-high (0.9-m) poultry netting provides
excellent protection.
Cultural Methods
Habitat Manipulation
In areas
where jackrabbit or hare damage is
likely to occur, highly preferred crops
such as alfalfa, young cotton plants,
lettuce, and young grape vines are
usually most damaged. Crops with
large mature plants, such as corn, usually
are not damaged once they grow
beyond the seedling stage. Where possible,
avoid planting vulnerable crops
near historically high hare populations.
Overuse of range forage can sometimes
lead to high jackrabbit numbers.
Jackrabbits are least abundant where
grass grows best within their range.
Like many rodents, they prefer open
country with high visibility to areas
where the grass prevents them from
seeing far. Thus, control programs
accompanied by changes in grazing
practices that encourage more vegetative
growth may be necessary for longterm
relief.
Frightening
Guard Dogs. Dogs can be chained
along boundaries of crop fields or near
gardens to deter jackrabbits.
Repellents
Since state pesticide registrations vary,
check with your local Cooperative
Extension or USDA-APHIS-ADC
office for information on repellents legal
in your area.
Various chemical repellents are offered
as a means of reducing or preventing
hare damage to trees, vines, or farm
and garden crops. Repellents make
protected plants distasteful to jackrabbits.
A satisfactory repellent must
also be noninjurious to plants.
In the past, a variety of repellents have
been recommended in the form of
paints, smears, or sprays. Many of
these afford only temporary protection
and must be reapplied too often to
warrant their use. Other, more persistent
materials have caused injurious
effects to the treated plants. Some
chemical substances such as limesulphur,
copper carbonate, and asphalt
emulsions have provided a certain
amount of protection and were harmless
to the plants. These are less commonly
used today and have been
replaced by various commercial preparations
such as ammonium soaps, capsaicin,
dried blood, napthalene,
thiram, tobacco dust, and ziram,
which are probably more effective.
Repellents are applied during either
the winter dormant season or summer
growing season. Recommendations
vary accordingly.
Be sure to use repellents according to
the manufacturer’s guidelines and follow
label recommendations.
Powders
Any repellent applications
that involve the use of powders should
be dusted on garden crops early in the
morning when plants are covered with
dew, or immediately after a rain. Do
not touch plants with equipment or
clothing because moist plants, especially
beans, are susceptible to disease.
When a duster is not available and
only a few plants are involved, use a
bag made of cheesecloth to sift repellent
dust onto plant foliage. Repeated
applications may be necessary after
rains have washed the powder from
the foliage and as new plant growth
takes place.
Sprays
Thoroughly cover the upper
surfaces of the leaves with spray repellent.
If a sprayer is unavailable and
only a small number of plants are
involved, a whisk broom or brush can
be used to apply the repellent to the
plant foliage. The repellents will
adhere to the foliage for a longer
period if a latex-type adhesive is used.
Reapply liquid repellents after a heavy
rain and at 10-day intervals to make
certain new plant growth is protected.
Some repellents are not registered for
application to leaves, stems, or fruits of
plants to be harvested for human use.
A list of registered commercial repellents
can be found in Supplies and
Materials. Many of these may be purchased
at a reasonable cost from suppliers
handling seed, insecticides,
hardware, and farm equipment.
Commercial repellents containing
thiram are effective and can be applied
safely to trees and shrubs. Treat all
stems and low branches to a point
higher than rabbits can reach while
standing on top of the estimated snow
cover. One application made during a
warm, dry day in late fall should suffice
for the entire dormant season.
Coal tar, pine tar, tar paper, and oils
have caused damage to young trees
under certain conditions. Carbolic acid
and other volatile compounds have
proved effective for only short periods.
For further information on repellents
and their availability, see Supplies
and Materials.
Toxicants
Since state pesticide registrations vary,
check with your local Cooperative
Extension or USDA-APHIS-ADC
office for information on toxicants
legal in your area. Be sure to read the
entire label. Use strictly in accordance
with precautionary statements and
directions. State and federal regulations
also apply.
Anticoagulants. In areas where they
are legal, anticoagulant baits may be
used to control jackrabbits. Varying
degrees of success have been reported
with diphacinone, warfarin, brodifacoum,
and bromadiolone. Anticoagulants
control jackrabbits and hares
by reducing the clotting ability of the
blood and by causing damage to the
capillary blood vessels. Death is
caused only if the treated bait is consumed
in sufficient quantities for
several days. A single feeding on anticoagulant
baits will not control
jackrabbits. Brodifacoum and bromadiolone
may be exceptions, but they
are not yet registered for use on jackrabbits.
Bait must be eaten at several
feedings on 5 or more successive days
with no periods longer than 48 hours
between feedings.
When baiting with anticoagulants, use
covered self-dispensing feeders or
nursery flats to facilitate bait consumption
and prevent spillage. Secure
feeding stations so that they cannot
be turned over. Place 1 to 5 pounds
(0.5 to 2.5 kg) of bait in a covered selfdispensing
feeder or nursery flat in
runways, resting, or feeding areas that
are frequented by jackrabbits. Inspect
bait stations daily and add bait as
needed. Acceptance may not occur until
rabbits become accustomed to the
feeder stations or nursery flats, which
may take several days. When bait in
the feeder is entirely consumed overnight,
increase the amount. It may be
necessary to move feeders to different
locations to achieve bait acceptance.
Bait should be available until all feeding
ceases, which may take from 1 to 4
weeks. Replace moldy or old bait with
fresh bait. Pick up and dispose of baits
upon completion of control programs.
Dispose of poisoned rabbit carcasses
by deep burying or burning.
Fumigants
There are no fumigants registered for
jackrabbits.
Trapping
Trapping with box-type traps is not effective
because jackrabbits are reluctant
to enter a trap or dark enclosure.
Snowshoe hares are susceptible to boxtype
traps.
Body-gripping and leghold traps can
be placed in rabbit runways. Trapping
in runways may result in unacceptable
nontarget catches. Check for tracks in
snow or dirt surfaces to be sure only
target animals are present. Placement
of sticks 1 foot (0.3 m) above the trap
will encourage deer and other large
animals to step over the trap while
allowing access to jackrabbits or other
hares. Be sure to check with local wildlife
officials on the legality of trapping
hares and jackrabbits.
Shooting
Where safe and legal to do so, shooting
jackrabbits may suppress or eliminate
damage. Effective control may be
achieved using a spotlight and a
shooter in the open bed of a pickup
truck. Driving around borders of crop
fields or within damaged range areas
and carefully shooting jackrabbits can
remove a high percentage of the population.
Some states require permits to
shoot from vehicles or to use spotlights.
In some states sport hunting of jackrabbits
can be encouraged and may
keep populations below problem
levels.
Other Methods
Predators
Natural enemies of jackrabbits
include hawks, owls, eagles,
coyotes, bobcats, foxes, and weasels.
Control of these predators should
occur only after taking into account
their beneficial effect on the reduction
of jackrabbit populations.
Economics of Damage
and Control
Jackrabbits consume considerable
vegetation. In cases where their overuse
of natural forage results in the
reduction of livestock on rangeland,
control measures may need to be
implemented. Few studies have been
conducted on the cost-effectiveness of
jackrabbit control on rangelands. Damage
must be extreme to justify expenditures
for control programs. In most
cases, cultural controls and natural
mortality will suffice to keep jackrabbit
populations in check.
Economic loss on croplands is much
easier to measure. In areas with historic
jackrabbit or hare damage, farmers
should anticipate problems and
have materials available to use at the
first sign of damage. During dry times
of the year or times of natural food
shortages, preventive measures such
as shooting and exclusion may be considered
a part of regular operations.
Jackrabbits and other hares can be deterred
most easily if control measures
are implemented before the hares
become accustomed to or dependent
on crops.
*The above information was taken from a University of Nebraska Web site with
express permission of Stephen Vatassel, wildlife damage project coordinator.
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