Build cup-shaped nests of dried vegetation in the burrow. Suitable areas for California ground squirrels are herbaceous sites, and openings in most brush and forest habitats. Friable soils are required, and rocks, scattered trees, logs, and other ground cover enhance the habitat. Timing of inactivity varies greatly with individuals, populations, weather, and habitat. Individual home ranges often overlap considerably.
Females are polyestrous.
Timing of breeding season varies greatly throughout California. Mating occurs from January through July, with peak activity in March through June. Females produce 1 litter per yr. California ground squirrels are important prey for many carnivores. Population numbers usually increase in heavily grazed areas, as forb production and visibility increase.