California is home to an abundant and diverse population of chipmunks, representing one of the highest species diversities in North America. These small, striped rodents have adapted to a wide range of environments across the state’s varied landscape. They are a common sight and sound in many of California’s forested and mountainous regions.
Identifying California’s Chipmunk Species
California’s mountains and forests host 13 different chipmunk species, each with unique markings. The Lodgepole Chipmunk (Tamias speciosus) is medium-sized, distinguished by bright orange sides and prominent dark and light stripes. The Alpine Chipmunk (Tamias alpinus) is the smallest and palest, weighing only one to two ounces, which helps it blend into high-elevation granite and talus slopes. This species is typically gray-brown with muted orange flanks and subtle striping. The Yellow-pine Chipmunk (Tamias amoenus) is slightly larger, possessing reddish-brown fur with five dark dorsal stripes alternating with four lighter ones.
Where Chipmunks Live in California
California chipmunks are creatures of elevation and forest cover, thriving in the state’s major mountain systems. Primary habitats include the Sierra Nevada and southern California ranges, such as the San Bernardino and San Jacinto mountains. The Alpine Chipmunk is found exclusively in the high Sierra Nevada, often at elevations between 7,500 feet and 12,800 feet, inhabiting rocky talus slopes and sub-alpine forests. Lodgepole Chipmunks occupy mid-to-high elevation subalpine coniferous forests, typically ranging from 5,000 to 10,000 feet. They are absent from the Central Valley and urbanized coastal areas. Other species, like the California Chipmunk (Tamias obscurus), are found in pinyon-juniper and chaparral habitats in southern desert ranges.
Chipmunks vs. Ground Squirrels: Key Differences
Chipmunks are often confused with ground squirrels, especially the Golden-mantled Ground Squirrel, due to similar size and markings. The key difference is the pattern of stripes on the head. Chipmunks have distinct dark and light stripes running across their face, extending from the nose to the ears and through or over their eyes. Ground squirrels lack these facial stripes, though many have prominent stripes along their back and sides. Chipmunks are also smaller, typically five to six inches in body length, compared to the nine-to-eleven-inch body of a California ground squirrel. When moving, chipmunks often carry their tail in a slightly upright position, while ground squirrels hold theirs lower.
Diet and Seasonal Behavior
The diet of California chipmunks is omnivorous, consisting of a wide array of plant and animal matter. They consume seeds from grasses and conifers, nuts, berries, fungi, and occasionally insects and bird eggs. Chipmunks possess large cheek pouches that they use to transport food back to their burrows for storage. Their seasonal behavior involves a period of winter inactivity known as torpor or restless hibernation. Chipmunks wake periodically throughout the winter to feed on the large caches of food they have stored underground. They are diurnal, meaning they are active exclusively during the day, with the greatest foraging activity typically occurring in the early morning and late afternoon.