The White-tailed jackrabbit is a large hare found in North America. It has distinctive, large, grey ears with black tips which are chestnut brown and white on the inside; and the long, powerful hind legs characteristic of hares. The back, flanks, and limbs are dark brown or greyish-brown and the underparts are pale grey. The tail is white with a dark central stripe above. Females are slightly larger than males. In northern populations, this hare molts in the autumn and becomes white all over except for its ears.
White-tailed jackrabbits are found in western and central parts of North America. Their range includes British Columbia, Alberta, Saskatchewan, Manitoba, and Ontario in Canada and Washington, Oregon, California, Nevada, Utah, Idaho, Montana, Wyoming, Colorado, New Mexico, North Dakota, South Dakota, Nebraska, Kansas, Minnesota, Wisconsin, Iowa, Missouri, and Illinois in the United States. Whitetails inhabit plains and prairie and alpine meadows with scattered coniferous trees. They are also often seen in suburban parks in Western Canada.
White-tailed jackrabbits are nocturnal animals; they rest during the day in a form, a shallow depression in the ground hidden under vegetation and emerge at dusk to feed. They are solitary and only come together during the breeding season. White-tailed jackrabbits have good eyesight, excellent hearing, and sensitive whiskers. They are very careful and try to evade detection by crouching in the vegetation where their cryptic coloration makes them difficult to observe. They may slink away, but if detected, they bound away at speed, adopting a zigzag course. They can run up to 55 km/hr (34 mi/hr) and leap up to 5 m (16 ft). Whitetails generally make no sound but will emit a shrill scream if they are injured or caught.
White-tailed jackrabbits are polygynandrous (promiscuous), meaning that both the males and females mate with multiple partners. Their breeding season is variable and depends upon latitude and environmental factors; it extends from February to July in different parts of the range. Several males may compete aggressively for the attention of a female by charging at each other, leaping, and jostling. The gestation period is about 42 days and in preparation for the birth, the female prepares a fur-lined nest under dense vegetation. A litter consists of up to 11 young, although 4-5 is a more typical number. The leverets weigh about 100 g (3.5 oz). They have their eyes open and are fully furred at birth and soon begin to move around. They start to forage around 2 weeks old and are weaned at 4 weeks. They become reproductively mature around 7 months old but do not breed until the year after their birth.
White-tailed jackrabbits are fairly common across most of their range, however, the population size may be declining slightly mainly due to habitat loss. Whitetails are also often killed because they are considered agricultural or garden pests. In parks and gardens, people often come across bunnies alone during the day in spring and mistakenly assume they are abandoned by their mothers and try to adopt them or bring them into animal shelters.
According to IUCN, the White-tailed jackrabbit is widespread throughout its range but no overall population estimate is available. Currently, this species is classified as Least Concern (LC) on the IUCN Red List but its numbers today is decreasing.
White-tailed jackrabbits play an important role in their ecosystem. They influence the composition of the turf through their selective grazing activities and they are also important prey species for various mammalian predators such as red and grey foxes, American badgers, coyotes, and bobcats.