[2] Rock squirrels are one of the largest members of the family Sciuridae, with adults measuring up to 21 inches (53 cm) in length.

[3] In front and on top, the squirrel's coat is a speckled grayish brown; on the rear and bottom, the gray becomes a more mottled brownish-black tone.

The rock squirrel is predominantly a herbivore, eating mostly leaves, stems, and seeds, and occasionally invertebrates and small vertebrates.

They also eat acorns, pine nuts, fruits of native plants, assorted grasses, mesquite, juniper berries, agaves and cacti.

[7] Rock squirrels forage for their food on a daily basis, by climbing trees and bushes or on the ground.

They eat some of the food right away and bring a significant portion back to a lookout point or burrow, where they can safely consume or store the rest.

Humans have also been known to eat rock squirrels, but can also view them as pests, resulting in lethal and nonlethal removal.

In the western edge of the range of these squirrels in the US, they mostly inhabit parts of southeasternmost corners of California, which includes some of the most arid areas in the entire state.