Mexican fox squirrel

The Mexican fox squirrel (Sciurus nayaritensis) is a tree squirrel of the Sierra Madre Occidental in Mexico, ranging south to Jalisco and north into the Chiricahua Mountains of southeastern Arizona, the only place it lives in the United States. It has a grizzled brown back, a yellow to rufous underside and a charcoal tail frosted with white, weighs around 700 grams and molts twice a year. It lives in pine and oak forests at lower elevations and in mixed conifer forests higher up, with the densest populations along riparian areas that have large cottonwoods and sycamores. The squirrel is active by day, does not hibernate, and spends much time foraging on the ground and in the canopy for tree seeds, flowers, fungi and insects. It builds ball-shaped nests of sticks and leaves, usually produces one small litter of one or two young, and is evaluated as Least Concern by the IUCN. Three subspecies are recognised, including the Chiricahua fox squirrel of Arizona.