Scientific Name: Genus Lepus
Jackrabbits are, properly speaking, not rabbits but hares, like the snowshoe hare. Hares have longer feet than rabbits and usually have longer ears. Most hares live in open country, whereas cottontails live in brushy habitats. Perhaps the most important distinction between them is that cottontails are born blind, nearly naked and helpless. Hares, by contrast, are born fully furred and ready to hop.
Snowshoe hares have relatively short ears for a hare, but their huge hind feet remind us that these are not rabbits. Jackrabbits are up to 2 feet long and weigh 6 to 9 pounds. Snowshoe hares weigh about half that. Black-tailed jackrabbits are a grizzly tan color year-round. Both white-tailed jackrabbits and snowshoe hares turn white in winter.
The white-tailed jackrabbit lives in mountain parks, sagebrush country, and native shortgrass prairie. The slightly smaller black-tailed jackrabbit lives in semi-desert country in southern and western Colorado, and on disturbed prairie in the east. Agriculture on the eastern plains probably has favored black-tailed jackrabbits over white-tails. Snowshoe hares live in sub-alpine forests, often in willow thickets.
Hares are vegetarians, eating tender herbs in summer, and woody twigs and bark in winter. They also are food for coyotes, bobcats, foxes, large hawks and owls, and many jackrabbits are killed by automobiles. Human harvest in Colorado varies widely, upwards of 10,000 annually.
Snowshoe hares produce two litters of five young annually, between March and August. Jackrabbits may have four litters. Gestation is about six weeks.
By David M. Armstrong Department of Ecology & Evolutionary Biology Environmental Studies Program, University Museum of Natural History University of Colorado-Boulder