Family: Heteromyidae, Pocket Mice and Kangaroo Rats view all from this family

Description A medium-size kangaroo rat. White below. Many hairs in top and bottom tail stripes have white bases, giving stripes a grizzled appearance. Crested tail about a 1 1/2 times body length; white tail stripe about half as wide as dark dorsal stripe. Hindfoot has 5 toes; soles of feet dusky. L 10 7/8-11 3/4” (277-300 mm); T 6 1/2-7 1/8” (164-180 mm); HF 1 1/2-1 5/8” (39-43 mm); E 1/2-5/8” (13-16 mm); Wt 1 1/8-1 3/4 oz (34-50 g).

Endangered Status The Stephens' Kangaroo Rat is on the U.S. Endangered Species List. It is classified as endangered in California. Agricultural development and encroaching urbanization have limited this kangaroo rat to isolated populations in its San Jacinto Valley range. Cattle grazing, off-road vehicles, the poisoning of other rodent pests, and other factors continue to threaten the species, and any one of these quite easily could wipe out an entire population.

Similar Species Most similar to Agile and Panamint kangaroo rats. Agile has dark rather than dusky soles on hindfeet; many, rather than few, white hairs in tail tuft; tail has broad, sharply demarcated white stripes. Panamint, which occurs north of San Jacinto Valley, has larger hindfoot.

Breeding Pregnant and lactating females have been found June-July. Litter averages 2 or 3 young.

Habitat Sparsely vegetated habitats of sagebrush or annual grasses.

Range Only in San Jacinto Valley and adjacent areas of w Riverside County; also sw San Bernardino and nw San Diego counties, California.

Discussion This species occurs with the Agile Kangaroo Rat, but Stephen’s is more abundant in areas of sparse vegetation. The Deer Mouse is sometimes its only associate. In captivity, this species has built elaborate nests up to a week prior to giving birth. Barn and long-eared owls are its major predators.