White-tailed Jackrabbit

The coat of white-tailed jackrabbits turns white during winter in Yellowstone and other areas with snow.

NPS

 

Considered an agricultural or garden pest in many parts of the country, the white-tailed jackrabbit (Lepus townsendii) found a niche in Yellowstone. Most of the park is too forested or accumulates too much snow to provide suitable habitat, but in lower elevation areas of the northern range it can feed on sagebrush, rabbitbrush, and other shrubs during the winter. The jackrabbit is preyed upon by bobcats, coyotes, wolves, eagles, hawks, and owls in the park, but perhaps because of its limited distribution, it does not appear to provide a significant source of food for these species.

 

White-tailed jackrabbit track

Number in Yellowstone

Common in suitable low elevation habitats in the park.

Where to See

Elevations below 6,500 feet from the Blacktail Plateau to Mammoth to the Gardiner Basin area.

Identification

• Easily distinguished from true rabbits by their large ears, large feet, and generally large body size.
• Use their ears to listen for danger and to radiate body heat. Large ears allow them to release excess body heat and tolerate high body temperatures.
• Summer coat is grayish brown, with a lighter underside. In Yellowstone and other places where there is persistent and widespread snow cover, the coat changes to nearly white in winter. Ears are rimmed with black.

Habitat

• Found in prairie-grassland and grass-shrub steppe habitat types in western high plains and mountains. They generally prefer grass-dominated habitats and have also been found to flourish above treeline in the alpine zone and avoid forested areas.

Behavior

• Have 1–4 litters per year with 1 to 15 offspring.
• Gestation is 36–43 days.
• In most areas, the breeding season of white-tailed jackrabbits averages 148 days and may run late February to mid July. Breeding in the northern Yellowstone ecosystem is not well documented.
• Feed on grasses, forbs, and shrubs at night and are less active during the day.
• Can run from 35 to 50 mph (56 to 80 kph) and cover 6–10 ft (2–3 m) with each bound. Will also swim when being pursued by predators.

 

Description

Despite its common name, the jackrabbit is more closely related to other hares than to rabbits (Sylvilagus spp.) Like the much smaller snowshoe hare (L. americanus), which resides in Yellowstone’s coniferous forests, the jackrabbit has a grayish-brown summer coat that turns nearly white to provide winter camouflage in areas with persistent snow cover. The slightly smaller black-tailed jackrabbit (L. californicus), which is found in lower elevation areas, has not been documented in the park and is generally less common in Greater Yellowstone.

 

Population

Nearly all of the 501 jackrabbit observations recorded in 2008 and spottier records prior to that were made in sagebrush-grassland habitat at elevations below 6,500 feet (2,000 m) where the average annual precipitation is less than 16 inches (40 cm). Less than 1% of the park (about 18,700 acres) is located in these areas, which are found in the Gardiner Basin, along the Gardner River, and in Mammoth Hot Springs. Although some jackrabbit populations are known to fluctuate markedly over the short- or long-term, no evidence has been found that the abundance or distribution of jackrabbits in Yellowstone has changed substantially since the park was established in 1872. Jackrabbits are found as high as 14,600 feet (4,200 m) in Colorado, but a limiting factor in Yellowstone appears to be snow, which begins to accumulate earlier in the winter, attains greater depths, and lasts later into spring with increasing elevation.

 

 

 

Resources

Gunther, K.A., R.A. Renkin, J.C. Halfpenny, S.M. Gunther, T. Davis, P. Schullery, and L. Whittlesey. 2009. Presence and distribution of white-tailed jackrabbits in Yellowstone National Park. Yellowstone Science 17(1): 24–32.

Barnosky, E.H. 1994. Ecosystem dynamics through the past 2000 years as revealed by fossil mammals from Lamar Cave in Yellowstone National Park. Historical Biology 8:71–90.

Lim, B.K. 1987. Lepus townsendii. Mammalian Species 288:1–6.

Streubel, D. 1989. Small mammals of the Yellowstone ecosystem. Boulder, CO: Roberts Rinehart.