General Distribution
The range of the southern California population of lodgepole chipmunk is discontinuous. This taxon
historically occurred on the upper slopes of the San Josito, San Jacinto, San Bernardino, San Gabriel,
and Piute Mountains of southern California (Best and others 1994), but has apparently been extirpated
from the San Jacinto Mountains (Callahan pers. comm.).
Historic records for lodgepole chipmunk include Whitewater Creek (7,500 feet [2,286 meters]) and Mt.
San Bernardino in the San Bernardino Mountains; French Gulch in the Piute Mountains; Fawnskin Park,
Sugarloaf, and Camp Angelus on the San Bernardino National Forest; and Dry Lake (9,000 feet [2,743
meters]) in the San Gorgonio Wilderness Area (Hall 1981). Systematics
Hall (1981) recognized four subspecies of lodgepole chipmunk (identified as Eutamias speciousus by
Hall) in California. T. s. frater and T. s. sequoiensis occur in northern and central California; T. s.
speciosus and Mount Pinos chipmunk (T. s. callipepulus) occur in southern portions of the state.
Because the Mount Pinos chipmunk is an isolated subspecies that is restricted to Mt. Frazier and Mt.
Abel on the Los Padres National Forest (Williams 1986), T. s. callipepulus and T. s. speciosus do not
overlap in range. Habitat Requirements
Throughout their range, lodgepole chipmunks are generally found in open-canopy forests with a mix of
shrubs and trees (Williams 1986). Lodgepole chipmunks typically occur in habitats with approximately
40 percent vegetation cover, numerous large boulders, and some open ground (Best and others 1994).
They are common in lodgepole pine forests, but also occur in open-canopy stages of other forest habitats
including white fir, Jeffrey pine, and mixed conifer. They appear to avoid pure stands of conifers,
preferring an understory shrub component (Stephenson and Calcarone 1999). The lodgepole chipmunk
is vulnerable to heat stress, which may preclude it from sagebrush, pinyon-juniper, and alpine habitats
(Chappell and others 1978, Heller and Gates 1971).
In southern California, lodgepole chipmunk occurs in lodgepole pine, chinquapin, manzanita, and
whitethorn in the San Gabriel Mountains, and in lodgepole pine forests in the San Bernardino Mountains
(Best and others 1994).
Lodgepole chipmunks are more arboreal than most other species of chipmunks (Sharples 1978). They
use trees for refuge, observation posts, and nests. They also use cavities in logs, snags and stumps, and
underground burrows (Brand 1974, Broadbooks 1974). Reproduction
The breeding season of lodgepole chipmunk occurs in May and June, about one month after emerging
from hibernation, and lasts approximately four weeks (Best and others 1994). In northern California,
this species produces one litter a year, and the number of young ranges from three to six. Young
reproduce the following spring (Best and others 1994). Lodgepole chipmunks use nests in burrows, and
in cavities in trees, logs, stumps, and snags. Daily/Seasonal Activity
Lodgepole chipmunks are secretive and diurnal (Best and others 1994). They are generally arboreal,
using trees for refuge, as observation posts, and for nests (Zeiner 1990), although underground dens are
also used in all seasons in southern California (Callahan pers. comm.).
In the laboratory, this species enters hibernation in late October to November and emerges in mid-April.
They hibernate in nests built in stumps, logs, and cracks and crevices of rock piles (Best and others
1994). They arouse every 1–2 days near the beginning and end of hibernation, but remain dormant for
periods of 5–6 days during the rest of the hibernation period.
In the San Bernardino and San Gabriel Mountains, the southern California subspecies of lodgepole
chipmunk was reported to be active and was observed outside of nests during every month of the year
(Best and others 1994). Diet and Foraging
Lodgepole chipmunks are omnivorous; although there is little information on the diet of the southern
California subspecies, lodgepole chipmunks in other parts of the state were observed eating seeds of
grasses, forbs, and trees; fruits and berries; insects; picnic scraps; and carrion (Best and others 1994).
They also eat fungi, which make up 32 percent of their annual dietary volume. A lodgepole chipmunk
in the San Bernardino Mountains was observed robbing eggs from the nest of a pair of western wood
pewees (Best and others 1994).
During summer and autumn, lodgepole chipmunks devote much of their time gathering food from the
ground and in shrubs and trees. They collect food in external cheek pouches and later cache it beneath
old logs, in rock piles, and in forks and foliage of trees (Best and others 1994).
Although lodgepole chipmunks accumulate fat in autumn, cached food provides the principal energy
source for the inactive period. Territoriality/Home Range
The average home range for lodgepole chipmunks in California is 3.68 acres (1.49 hectares) for adult
males, 3.16 acres (1.28 hectares) for breeding females, and 3.95 acres (1.60 hectares) for young females
(Best and others 1994). In Yosemite National Park, the average home range was found to be 6.42 acres
(2.60 hectares) (Best and others 1994).
Lodgepole chipmunks in the Sierra Nevada are highly aggressive with other chipmunk species,
including alpine chipmunk (T. alpinus), yellow-pine chipmunk (T. amoenus), and least chipmunk (T.
minimus) (Zeiner 1990), although such aggression has not been observed in southern California
(Callahan pers. comm.). Although these species are sympatric (i.e., occupying the same area),
competitive exclusion separates them along altitudinal zones (Best and others 1994). Predator-Prey Relations
Common predators of lodgepole chipmunks include coyote, foxes, bobcat, marten, Cooper's hawk, and
red-tailed hawk (Best and others 1994, Zeiner 1990). Literature Cited
Best, T.L.; Clawson, R.G.; Clawson, J.A. 1994. Tamias speciosus. Mammalian Species 478: 1-9.
Published by the American Society of Mammalogists.
Brand, L.R. 1974. Tree nests of California chipmunks. American Midland Naturalist 91: 489-491.
Broadbooks, H.E. 1974. Tree nests of chipmunks with comments on associated behavior and ecology. J.
Mammal. 55: 630-649.
Chappell, M.A.; Calvo; A.V.; Heller, H.C. 1978. Hypothalamic thermosensitivity and adaptations for
heat-storage behavior in three species of chipmunks (Eutamias) from different thermal environments. J.
Comp. Physiol. 125: 175-183.
Hall, E.R. 1981. The mammals of North America. 2d ed. New York: John Wiley & Sons.
Heller, H.C.; Gates, D.M. 1971. Altitudinal zonation of chipmuunks (Eutamias): Energy budgets.
Ecology 52: 424-433.
National Biological Service (Ed.). 1995. Fact sheet. Success with species at risk – southern California
lodgepole chipmunk. [Homepage of U.S. Geological Survey], [Online]. Available: http://biology.usgs.
gov/pr/factsheet/chipmunksar.html.
Sharples, F.E. 1978. Resource partitioning in four sympatric species of Eutamias in the northern Sierra
Nevada. Davis: University of California; 94 p. PhD. dissertation.
Stephenson, J.R.; Calcarone, G.M. 1999. Southern California mountains and foothills assessment:
Habitat and species conservation issues. General Technical Report GTR-PSW-172. Albany, CA: Pacific
Southwest Research Station, Forest Service, U.S. Department of Agriculture.
Verner, J.; Boss, A.S. 1980. California wildlife and their habitats: Western Sierra Nevada. USDA,
Forest Service General Technical Report PSW-37; 439 p.
Williams, D.F. 1986. Mammalian species of concern in California. California Department of Fish and
Game Report. Sacramento, CA: California Department of Fish and Game.
Zeiner, D.C.; Laudenslayer, W.F., Jr.; Meyer, K.E.; White, M., eds. 1990. California's wildlife. Volume
III: Mammals. California statewide wildlife habitat relationships system. Sacramento, CA: California
Department of Fish and Game.
Information gathered from California DFG - California Interagency Wildlife Task Group
