Family: Muridae, Mice and Rats view all from this family

Description Grayish to brownish above; yellowish to white below. Populations that inhabit lava flows may be blackish above. Tail distinctly bicolored, black to dusky above, grayish to white below. Throat hair gray at base. L 11 3/8 -16 5/8" (290-417 mm); T 4 1/8 -8 1/8"(105-206 mm); HF 1 1/4 -1 5/8" (31-41 mm); Wt 5-6 1/2 oz (140-185 g).

Similar Species White-throated and Southern Plains woodrats have throat hair white at base. Desert Woodrat, difficult to distinguish, is more grayish below, and its tail is less strongly bicolored.

Breeding In Colorado, breeds March-May with litters April-June; in South, breeds longer, but few details available; litters of 1-3 young; gestation 33 days. Reaches sexual maturity as early as 2 months of age.

Habitat Rocky outcrops, slopes, and cliffs in mountains; most common in pinyon-juniper and ponderosa pine forests, but may occupy a variety of other habitats.

Range Southeastern Utah, c and s Colorado, w Arizona, most of New Mexico, and w Texas.

Discussion The diet of the Mexican Woodrat includes green plants, pinyon nuts, juniper and other berries, nuts, acorns, and fungi. This animal also eats cacti, although cacti are not present in many of the higher areas it inhabits. In Colorado, for instance, it cures and stores great quantities of foliage. Rather than building a typical nest, the Mexican Woodrat often nests in a rocky crevice, fortifying it with a blockade of sticks, vegetation, and other debris, although collecting tendencies are not as pronounced as in some other species. In less rocky areas, its nests may be located in hollow trees, brush piles, or buildings. Like most woodrats, this species engages in foot-drumming, scent-marking by perineal dragging (lowering the rump while dragging itself along), and rolling on the back. Males, which have a scent gland only on the belly, also use abdominal rubbing for scent-marking.