Family: Sciuridae, Squirrels view all from this family
Description Brownish, with prominent buff flecks; whitish wash from sides of neck across shoulders and forelegs to haunches, enclosing a dark brown or black, forward-pointing V pattern on upper back. Rather bushy tail, brownish gray above and below, edged with white. L 14–19 3/4" (357–500 mm); T 5 3/4–8 7/8" (145–227 mm); HF 1 7/8–2 1/2" (49–64 mm); Wt 9 7/8–26 oz (280–738g).
Similar Species Other ground squirrels in range are smaller and lack V pattern and whitish wash.
Breeding Mates in early spring. 1 litter per year of 5–8 young, born in May. Time of births varies with locality.
Habitat Open areas, including rocky outcrops, fields, pastures, and sparsely wooded hillsides.
Range South-central Washington, w Oregon, most of California, and wc Nevada.
Discussion Active from dawn to dusk, the California Ground Squirrel hibernates from November to February; first-year animals often remain aboveground through the winter. While this ground squirrel may climb into brush or a tree to bask in early-morning sunlight, it otherwise remains on the ground. It sometimes consumes insects and small vertebrates, but primarily feeds on plant material, including leaves, stems, flowers, bulbs, roots, seeds, fruits, and berries; it often damages grain, fruit, and nut crops. These squirrels form loose colonies, but individuals tend to be antisocial. Young first begin to burrow at about eight weeks of age. Several animals may occupy one burrow, which typically is 3 to 6 inches (75–150 mm) wide and 5 to 200 feet (1.5–60 m) long. Each animal uses its own entrance, and it is usually to this hole, rather than the nearest, that it races when alarmed. Burrows are generally under a log, tree, or rock when one is available, but are otherwise in the open, with a mound at the main entrance. Some are used for many years by successive occupants. The fleas of this ground squirrel sometimes carry bubonic plague.
