Lepus californicus, the Black-tailed Jackrabbit, is also sometimes called the California Jackrabbit. It is a member of the family Leporidae in the Lagomorpha order. Hares as a group do not burrow, instead, they conceal themselves in vegetation as you can see in the picture above. This fellow has both of his elongated ears tuned in on me while I took his picture.
In the second picture, he is less interested in my presence but he is still keeping an ear pointed in my direction. These inhabitants of open grassland and deserts of the western U.S. have keen senses of hearing and sight which helps them survive predators while they are active at twilight and into the night. Desert dwelling mammals often have large ears because it helps them detect predators sooner in the open conditions of these environments. The Black-tailed Jackrabbit, like all the Lagomorpha, are vegetarian consuming grass, wild plants, cactus, and mesquite pods and shoots. They will also eat crops planted by farmers and can become problematic when their numbers increase dramatically. Apparently their population cycles from low to high over a period of nine or ten years.
In the last picture, you see our subject in flight down a row in a cotton field. Their senses and the ability to run farther and faster than their rabbit neighbors keeps them free from being eaten by foxes, coyotes, hawks, and large owls. Also, notice the black marking on the rump and tail, it’s the character for which they are named.
For more information, you can consult the U. S. Forest Service’s Fire Effects Information site which has a database about mammals and other animals. Wikipedia is another place to visit, too. You can find a picture of the range of this species and a list of all 17 subspecies.