Rock squirrels are one of the largest members of family Sciuridae. In front and on top, their coat is a speckled grayish brown; on the rear and bottom the gray becomes a more mottled brownish-black tone. They have a marked light-colored ring around their eyes and pointed ears that project well above their heads. Rock squirrels have a long bushy tail with white edges.
Rock squirrels are native to Mexico and the southwestern United States. They occur from Nevada, Utah, and Colorado, south through Texas and California to southernmost Puebla, Mexico. These squirrels inhabit rocky canyons, cliffs, talus slopes, canyon walls, and hillsides. They also live in urban areas.
Rock squirrels are active in the early morning and late afternoons when it is warm. When it is very hot, they may estivate. These squirrels forage during cool mornings by climbing trees and bushes or find their food on the ground. They eat some of the food right away and bring a significant portion back to a safe place, where they can consume the rest. Rock squirrels are social creatures and live in colonies with several females and one dominant male who fights other mature males to protect the group. Rock squirrels live in burrows which they dig with their sharp claws and muscular legs. These burrows provide shelter, safety, living space, and food storage. Burrow systems can be complex and lengthy, as they are enlarged over a period of years. Entrances are usually hidden beneath rocks. In the northern part of their habitat, Rock squirrels hibernate during the colder months of the year. In southern areas, they may not hibernate at all. These squirrels can withstand long periods of time without water, some even up to 100 days. In order to communicate with each other Rock, squirrels use greeting behavior, sniffing, touches and different calls. When alarmed, they whistle a short, sharp, oscillating call.
Rock squirrels are predominantly a herbivore, eating mostly leaves, stems, and seeds. They also eat acorns, pine nuts, and fruits of native plants, including cacti. Occasionally, Rock squirrels consume insects or the eggs of small nesting birds. They may also eat their own kind, scavenging the remains of squirrels that are already dead.
Rock squirrels are polygynous where males mate with more than one female during the breeding season. Females have two litters a year, with 3 to 9 young in each litter. The first litter is typically born between April and June, while the second is born between August and September. The gestation period lasts around 30 days. Newborn babies stay in the burrow and nurse around 2 months and begin foraging for food themselves about 3 days after they leave the burrow. Young remain on their mother's home territory and may use the same burrow around 14 weeks after emergence. After babies leave burrows, mothers protect them at least until hibernation. The mother and her babies use nose touching to recognize each other and to greet. When 1-year-old, young females often remain near their home burrows and young males usually disperse to new areas. Rock squirrels reach reproductive maturity at different ages depending on locations and populations.
Currently, there are no major threats to Rock squirrels.
The IUCN Red List and other sources do not provide the Rock squirrel total population size, but this animal is common and widespread throughout its known range. Currently, this species is classified as Least Concern (LC) on the IUCN Red List and its numbers today are stable.
Rock squirrels play an important role as plant dispersers. They bury nuts and seeds they consume near their burrows and then forget about them. These squirrels are also an important food source for local predators.