Family: Muridae, Mice and Rats view all from this family
Description Dark brown or blackish, coarsely grizzled with cream above; grayish below. Scaly, scantily haired tail less than half total length; dark above, slightly paler below. L 8 1/8–14 3/8" (207–365 mm); T 3–6 1/2" (75–166 mm); HF 1 1/8–1 5/8" (28–41 mm); E 5/8–7/8" (16–24 mm); Wt 2 3/4–4 1/4 oz (80–120 g).
Similar Species Rice rats generally have longer tails and paler fur on tops of hindfeet. Yellow-nosed Cotton Rat has orange or buff nose. Tawny-bellied Cotton Rat is tawny or buff below. Hindfoot of Arizona Cotton Rat averages larger.
Breeding Several litters per year of 1–15 young each; gestation 27 days. Newborn weighs 1/4 oz (7.2 g).
Habitat Grassy and weedy fields.
Range Southeastern Arizona, New Mexico, and se Colorado east to Virginia and south through Florida. Isolated populations in se California and sw Arizona.
Discussion Cotton rats are active around the clock, but especially from dusk to dawn, often climbing about aboveground in vegetation. They primarily consume green vegetation, cutting grass plants into sections to reach the heads, and can cause great destruction to crops such as sugarcane and sweet potatoes.They also eat a few insects and at times reduce quail populations by eating the eggs and chicks. The Hispid Cotton Rat makes long, shallow runways with nest chambers. Populations in the northern parts of its range make larger and more tightly woven nests than those in more southerly areas, with the openings usually facing toward the southeast, thereby reducing cooling by northwest winds. The Hispid Cotton Rat is one of the most prolific of mammals, breeding as early as six weeks of age. Its enormous reproductive potential is kept in check by its many predators, including other mammals, birds, and reptiles.
