| 03/01/2013 Picture Notes: While hiking the Yucca Peak Fossil Beds inside the Desert National Wildlife Range, I came upon a relatively young, black-tailed jackrabbit (Fig. 01). After surprising him by walking up to a bush that he was sitting next to, he ran to a distance of only about twenty feet away (Fig. 02), stopped with his back to me, and then to my utter surprise, sat motionless for several minutes, allowing me to snap a series of pictures. At first he was standing, however as I approached, he laid on the ground with his ears tucked back (Fig. 03). Eventually, I was able to walk all the way around him, to the point that he was staring directly at me (Fig. 04). After he bolted the second time, I captured the picture in (Fig. 01) from a distance of about fifty feet with my 20x zoom lens. So far, my experience with these critters is that they have very acute eyesight and hearing that allows them to quickly detect potential danger, causing them to run away at very high speeds. |
Description: The black-tailed jackrabbit (Lepus californicus), commonly known as the American desert hare, is native to the western United States and Mexico. Its ears have a black patch at the tip and is nearly as long as the hind foot. The top of the tail has a black stripe that extends onto its rump, The under-parts are usually clear; upper-parts have a dark buff, heavily sprinkled with blackish hair.
Full grown, it can reach a length of between 16-28 inches, head to tail, with a tail between 2-5 inches and ears up to 8 inches long. Their huge ears are used to regulate its body heat by increasing or decreasing blood flow. This helps the jackrabbit absorb heat or cool off. Smaller than the female, male jackrabbits can weigh from 9-11 pounds, while females are usually 11-13 pounds. It is the third largest North American hare, after the antelope jackrabbit and the white-tailed jackrabbit. The black-tailed jackrabbits occupy mostly mixed shrub-grassland terrains. The black-tailed jackrabbit does not migrate or hibernate during winter and uses the same habitat of between .5 and 1.5 square miles year-round. Its diet is composed of various shrubs and small trees during fall and winter months and grasses and forbs in spring and early summer. Nevada has a high black-tailed jackrabbit population and the animal has historically been unprotected in the state.
They typically bread in the spring, but depending upon location may continue all year round in warm climates. Their young are borne fully furred with eyes open. The jackrabbit's eyes are situated on the sides of its head, giving it all-around vision which enables it to spot danger coming from any direction. The soles of a jackrabbit's feet are covered with fur. This cushions their feet on hard ground and insulates them from the scorching heat of the desert sand. Their fur is a silver and tan color that blends in well with the desert and chaparral habitat that it lives in. Because they are well camouflaged and mobile within minutes of birth, the females do not protect or even stay with the young except during nursing. Average litter size is around four, but may be as low as two and as high as seven in warm regions. They grow rather rapidly and reach adult size in about 7 or 8 months. The natural enemies of rabbits include the larger birds of prey and such carnivores as coyotes, foxes, bobcats, badgers, and weasels. Jackrabbits always seem to be on their guard, very alert to their surroundings and watchful of potential threats. When molested it depends its keen senses of hearing and sight to detect danger and relies on its speed, up to 36 mph, to elude predators.
Strict vegetarians, they feed on clover, alfalfa and other abundant greens during spring and summer. During the lean fall and winter months, they subsist on woody and dried vegetation. They leave their resting spots at dusk to feed on tough grasses, leaves, and twigs and will also eat sagebrush and cacti. They only come out at night to feed. They conserve water by eating their food twice. Jackrabbits are coprophagic, meaning they eat their own waste . When eating their feces the second time, they can absorb more of the moisture and nutrition that was missed in the first digestive process. Jackrabbits rarely have to drink and get most of their water from the plants they eat.
Black-tailed Jackrabbits mate year around. They have one to four litters per year with one to eight young per litter. Young jackrabbits are born bright-eyed and active, and after only one month they can fend for themselves. They reach sexual maturity in 1 year. After mating, the female, or doe, will have a litter of 1-6 leverets every 3-4 months. The mother will leave the leverets in separate hiding places, and come back in the evening to nurse each one. After one month they are on their own. When the young are weaned after 3 weeks, the female mates again and produces another litter. In the wild they have a life span of 1-5 years.
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