Round-tailed ground squirrel

The round-tailed ground squirrel (Xerospermophilus tereticaudus) lives in the desert of the southwestern United States and northwestern Mexico, including northeastern Baja California and the state of Sonora. It is called a ground squirrel because it burrows in loose soil, often under mesquite trees and creosote bushes. Adults weigh around 125 grams and measure roughly 204 to 278 millimetres including a long round tail, with long hairy hind feet and a uniform sandy coat that matches the soil. It is omnivorous, eating mostly green vegetation along with seeds and insects, and it favours foods with high water content. Gestation lasts 28 days and litters average 5.4 pups. It stays active even on hot days, though it limits activity in the afternoon heat, and spends the winter underground in torpor without truly hibernating. It has a semi-colonial social structure and warns others of danger with a high-pitched alarm call, and snakes are its greatest predator.