 |
WHITE-TAILED JACKRABBIT
Lepus townsendii
Family Leporidae - Hares and Rabbits
Order Lagomorpha - Hares
Risk Status
Official status
The White-tailed Jackrabbit probably is extirpated in British Columbia
and is therefore on the Provincial
Red List ( CDC = G5
SH). COSEWIC
has not examined this species, but it is considered secure nationally
given its presence on the prairies. The provincial status of SH refers
to the fact that there have been no confirmed breeding records in
British Columbia in about 50 years.
Image Credits: Top sketch by Michael
Hames for the Royal British Columbia Museum. Bottom sketch in The
Mammals of British Columbia, Cowan and Guiguet, 1978.
Historical facts
The last sighting in British Columbia was in 1981, and the last
museum specimen was taken in 1957. Unconfirmed recent sightings
exist, but there are no confirmed breeding records in recent years.
Before extirpation,
White-tailed Jackrabbits were restricted in British Columbia to
the southern Okanagan and Similkameen Valleys of British Columbia
(Osoyoos to White Lake, Oliver, Chopaka north to Keremeos in Similkameen
and Okanagan Falls). In Canada they still exist in Alberta, Saskatchewan,
and extreme south western Ontario.
Distinguishing features
The White-tailed Jackrabbit is a large hare with pale grayish
brown dorsum, and
most have a thin brownish to grayish black mid-dorsal stripe. The
ears are dark grizzled-grey in front with white outer rims, greyish
white behind, and have prominent black tips. The throat is greyish,
they belly, tail and feet are white. The pelage is thin and coarse.
The undercoat is pale grey; the long guard hairs have dark grey
intermediate bands and long buffy tips.
White-tailed Jackrabbits are greyish-white in the winter except
for blackish ear tips. When the long guard hairs are parted, the
buffy-grey underfur shows through despite the winter coat. There
are two annual moults:
October to November, and April to May. After the snow has melted
in late spring, white hares are occasionally seen contrasting sharply
with a darker background.
White-tailed Jackrabbits have long ears, long legs, and large
body in comparison to the snowshoe hare. It is a relatively slim
hare with slender legs and a long white tail. They average about
3 kg, but may grow to 6 kg.
Distribution
British Columbia
In British Columbia, White-tailed Jackrabbits are known only in
the southern Okanagan Valley from Osoyoos Lake to Summerland, below
an elevation of 600 m. The species is at the northern periphery
of its range in the United States, and only rarely is sighted, and
possibly extirpated
in British Columbia.
North America
The White-tailed Jackrabbit subspecies (L. t. townsendii)
is found from California and Nevada, north to British Columbia,
and their numbers have declined in the northern parts of Washington
State in recent years. The second subspecies (L. t. campanius),
occurs in the prairie portions of Alberta, Saskatchewan, and extreme
south-western Ontario, and in western United States as far south
as northern New Mexico and central California in the United States.
Habitat
White-tailed Jackrabbits use different habitat
depending on season; sagebrush habitat and agricultural areas from
valley bottoms to 600 m altitude are the usual habitat. In eastern
Washington, they shift from arid, hilly bunchgrass in summer to
lower sagebrush valleys in winter. Jackrabbits also frequent pastures
and cultivated fields, bordered by willow thickets and wild rose
tangles, as well as the native short-grass sagebrush plains. They
seldom penetrate wooded areas, except when seeking shelter from
winter blizzards. Jackrabbits also burrow in snowbanks or crouch
in shallow depressions in the winter, with only their backs, flattened
ears, and eyes showing above the snow surface. In the summer, they
build shallow depressions at the base of bushes, rocks, or other
shelter for resting sites and as nests. Jackrabbits also seek shelter
in badger burrows.
Why is it endangered?
Jackrabbits probably disappeared in British Columbia as a result
of over-hunting, habitat loss and habitat fragmentation.
The White-tailed Jackrabbit was locally abundant, but numbers were
reduced because of cultivation, destruction of natural grassland,
and extermination by farmers who viewed Jackrabbits either as pests,
or sources of fur. Jackrabbits require a large home range, estimated
up to 89.4 hectares in a study in Colorado. Intense urban, agricultural,
and industrial development in the Okanagan region has eliminated
much of the natural habitat available to Jackrabbits. Since Jackrabbits
can cause agricultural damage, they are not welcome around farms
and orchards. Cattle grazing also impacts the quality of habitat
that may be shared with Jackrabbits. Being inefficient foragers,
Jackrabbits are unable to tolerate changes in food abundance or
diversity.
Severe winter conditions increase mortality and may reduce reproductive
output the following spring. In contrast, in mild winters, snow
may be patchy and Jackrabbits in their winter coat are far more
obvious to predators when viewed against bare ground. Wet weather
also increases juvenile mortality.
In addition to large predators, White-tailed Jackrabbits are succeptible
to diseases and parasites, including tularaemia, Colorado tick fever,
equine encephalitis and fever from botfly larvae infestations. Occasionally,
they are hunted by humans for sport and meat (outside of British
Columbia).
Biology
Breeding
The few sightings of adults in the Okanagan region and the fact
that there have been no recorded sightings of juveniles in the last
10 years, suggests that White-tailed Jackrabbits are extirpated
in BC.
The breeding season begins in late February, and young are born
in June to early July with an average litter size of 4 (ranging
from 3-6). Jackrabbits exhibit breeding synchrony
and have a post partum estrus
that allows conception right after parturition.
Females probably only bear one litter per year in the north, and
may have 3-4 litters per year in southern regions. New-born jackrabbits
are precocious. They are about 100 g at birth, with fur and open
eyes, and are concealed in an abandoned burrow, cavity, or shallow
"form." They are nursed by their mothers until they are
about a quarter grown, at the age of five to six weeks (towards
the end of July). In three to four months they reach adult size.
Behaviour
White-tailed Jackrabbits usually are nocturnal
and most active at dusk, early morning, and on moonlit nights. They
are frequently observed crossing roads at night. Jackrabbits are
active throughout the year as are all lagomorphs.
During the day, Jackrabbits hide under a bush or shrub or simply
hidden in tall grass and they are seldom seen unless flushed from
cover. Jackrabbits usually lie low, ears pressed back over its back
and eyelids half-closed over its yellow irises. They usually do
not flush until the intruder is within a few steps, and then it
springs into the air. Speed, in bursts up to 74 km/h, allows Jackrabbits
to escape predators. After short bursts, Jackrabbits settle into
a series of low gliding leaps, which may cover from 1.2 - 2.1 m
of ground. Jackrabbits also are strong swimmers and may plunge into
a river when pursued and swim (with much splashing) to the other
side.
Jackrabbits are silent except for their shrill screams when wounded.
A captured jackrabbit is not helpless and will bite, and scratch
with its long hind claws.
White-tailed Jackrabbits are one of the least social lagomorphs.
Hares generally are solitary, but small groups of three or four
may occasionally be observed in the mating season. Groups of 50-100
individuals have been observed during the day in Saskatchewan.
Diet or Growing requirements
Jackrabbits are herbivorous and travel and forage along well-worn
trails. They get water from their food. Their summer diet consists
of green vegetation including clover, cultivated grains, alfalfa,
and other crops, native grasses and some forbs. In the winter, they
eat dried grasses, roots, buds, twigs, and the bark of berry and
fruit trees. Jackrabbits eat their own soft fecal pellets (coprophagy).
They also eat lettuce and cabbage and may eat agricultural crops
or damage orchards in drought or in winter, and may gather near
haystacks for shelter and food. The jackrabbits also require salts
and minerals, which they get from mineral soils.
Predators
Jackrabbits are prey for coyotes, wolves, and foxes. In the south,
bobcats and eagles are their predators. They also are take by larger
hawks and owls. They are known to use man-made structures, including
barbed-wire fences to escape predators.
Sources of more information
Related On-line Sites to Visit
Publications
The Mammals of BC , Nagorsen, 1990
Our Living Legacy, 1993, RBCM
The SOCAP Workshop Summary, The Nature Trust, 1989.
Habitat Conservation Fund, August 1992.
Jones, J.K. and E.C. Birney. 1988. Handbook of Mammals of the
North-Central States. University of Minnesota Press.
Museum Specimens
this section sponsored
by: 
Industry Canada
|
