Yellow-pine Chipmunk

activity

Activity patterns. The Yellow-pine Chipmunk is diurnal and hibernates during the winter months, emerging in April. Nests are built in burrows, which are usually under logs, stumps, and rocks, although occasionally a grassy nest built in vegetation is reported. It appears to be more sensitive to temperature extremes than other species of Tamias. Testosterone levels in plasma appearto affect the overwinter survivability of the Yellowpine Chipmunk by reducing levels of glucocorticoid, and thusfat reserves.

Sciuridae

biology_ecology

Habitat. Dry forests in the transition zone, but may inhabit lower areas in the Canadian zone. The Yellow-pine Chipmunk can be found at elevations of up to ¢. 3000 m in the extreme south ofits distribution. It appears to prefer open areas and can be found on meadows with forbs, grasses, and sedges, but also in brushy habitats usually associated with Jeffrey pine (Pinusjeffreyi, Pinaceae) or lodgepole pine (P. contorta). It can be very abundant in degraded areas, such as logged forests, regenerating stands, and clearcuts, and several studies indicated higher capture rates in these areas than in primary or mature forests.

Sciuridae

biology_ecology

Movements, Home range and Social organization. Reported population densities vary 1 - 2 - 7 ind / ha, depending on location and habitat characteristics. The Yellow-pine Chipmunk is territorial and aggressive toward other Tamias species, being sometimes dominant over the Least Chipmunk (7. minimus), but subordinate to Townsend's Chipmunk (7. townsendii). This interaction with other Tamias species may affect the elevational distribution of the Yellow-pine Chipmunk in part of its distribution.

Sciuridae

breeding

Breeding. The Yellow-pine Chipmunk appears to have a promiscuous mating system, with low variability in male mating success. Mating season occurs late April to early May, a few weeks after the end of hibernation. Females produce onelitter per year. Gestation lasts ¢. 28 - 30 days and average litter size is 4 - 5 young, with a maximum of nine. Young weigh ¢. 2 - 6 g. There is strong evidence for sperm competition and little evidence for inbreeding. Young are weaned at c. 6 weeks and reach sexual maturity at c. 1 year.

Sciuridae