With distinctive long ears and long powerful rear legs like other jackrabbits, the black-tailed jackrabbit, an inhabitant of San Bernardino County, can reach a length of two feet and weigh anywhere from three-and-a-half to six pounds.
The third largest of North American hares, the Lepus californicus can be vicious, and, according to Mexican legend, will attack and even kill humans who are lost, weakened or disoriented in the desert. The species ranges throughout the deserts of the Southwest and into Mexico, where they have been referred to as “El Conejo de Muerta (The Rabbit of Death).”
Black-tailed jackrabbits are not rabbits but hares and, sporting 24 chromosomes, they cannot interbreed with domestic rabbits, which have 22 chromosomes.
The black-tailed jackrabbit’s dorsal fur is a dark buff sprinkled with black and is creamy white on its underside and the insides of its legs. The ears are black-tipped on the outer surface, with no pigment inside. The tail’s ventral surface is grey or white, and the tail’s dorsal surface is black, forming a black stripe. Females are larger than males.
Black-tailed jackrabbits generally occupy mixed shrub-grassland terrains and in California prefer chamise and chaparral, while avoiding closed-canopy chaparral. Strict vegetarians, black-tailed jackrabbits forage shrubs, grasses, sagebrush, and creosotebush, broom snakeweed, mesquite, yucca and cacti. They drink rainwater, springwater or dew when it is available but rely mostly on acquiring water from the plants they eat.
Male black-tailed jackrabbit reach sexual maturity at about seven months of age. Females usually breed in the spring of their second year, although females born in spring or early summer may breed in their first year. Ovulation is induced by copulation. There are two peak breeding seasons in California, one lasting from January to March and the other in June. The gestation period ranges from 41 to 47 days. In California the average litter size is three.
Female black-tailed jackrabbits do not prepare an elaborate nest, but rather give birth in shallow excavations called forms that are no more than a few centimeters deep which are sometimes bare or sometimes lined with hair prior to giving birth. Young are borne fully-furred with eyes open, and are mobile within minutes of birth. Other than for nursing, which lasts for no more than eight weeks, females do not hover around, stay with or protect their young. Siblings will stay together for about a week after leaving the form and then move out on their own.
Black-tailed jackrabbits do not migrate or hibernate during winter; staying in place. On a daily basis, however, they may move about anywhere from two to ten miles, staying within or near shrub cover during the day and foraging at night.
A black-tailed jackrabbit can reach a speed of 40 miles per hour and leap well over ten feet, allowing it to outrun most of its natural predators. The hares also sprint in a zig-zag pattern, further confounding their pursuers. The species’ natural predators include hawks, owls, eagles, coyotes, dogs, foxes, badgers, mountain lions, housecats, bobcats and snakes. Raccoons and skunks will prey on young black-tailed jackrabbits.
Despite the somewhat dubitable legend that black-tailed rabbits have on occasion actually killed humans, the reverse is in fact far more common. The hares are known to destroy crops and for that reason are not suffered gladly by farmers. In the 1930s and 1940s, there was a bounty on jackrabbits in the area in and around Hesperia. As many as 35,000 of the creatures may have been killed in a single exterminating go-round.
The black-tailed jackrabbit has somehow withstood the onslaught of human destruction, in some measure because of its prolific breeding capability but also, paradoxically, because the parasites that hector it are even more loathsome to humans.
The black-tailed jackrabbit population is riddled with ectoparasites, such as fleas, ticks, lice, and mites, as well as endoparasites including trematodes, cestodes, nematodes, and botfly (Cuterebra) larvae. Black-tailed jackrabbits are diseased with tularemia, equine encephalitis, brucellosis, Q fever, and Rocky Mountain spotted fever. As such, informed humans are reluctant to catch black-tailed jackrabbits as game. Those who do are well advised to wear gloves while handling carcasses and to cook the meat thoroughly to avoid contracting tularemia, which can result in death.