Least Chipmunk

activity

Activity patterns. The Least Chipmunkis terrestrial, but sometimes climbs brush and trees to forage or even to build a leaf nest in branches or woodpecker cavities. It is diurnal and during winter, enters torpor from October-November to March-April. Most nests are built underground in a burrow system that can have up to four entrances, and can be 0 - 4 - 3 - 5 m in length; usually the nest is not deeper than 20 cm below the surface.

Sciuridae

biology_ecology

Habitat. Open and arid shrublands. The Least Chipmunk can move to other habitats when its preferred areas are occupied by other more aggressive species. For instance, on the eastern slopes of the Sierra Nevada, in California, the aggressive Yellow-pine Chipmunk can displace the Least Chipmunk to shaded pinyon pine areas. The Least Chipmunk also occurs in upland riparian habitat along the Green River.

Sciuridae

biology_ecology

Movements, Home range and Social organization. The average home range is estimated to be 1 - 2 ha for males and 0 - 66 ha females, in Alberta, Canada. The Least Chipmunk is considered to be trap shy, and is probably underrepresented in trap surveys. It also appears to be subordinate to more aggressive congeners and other ground squirrels, butis able to coexist in some environments, probably due to its efficiency in resource exploitation. It is very vocal, with 5 - 6 different types of alarm calls and several other types of vocalizations; however, a detailed analysis ofits vocalization system 1 s needed.

Sciuridae

breeding

Breeding. Females enter estrus within seven days of emergence from hibernation, and mating season occurs between early April and mid-May. Gestation is ¢. 28 - 30 days and newborns weigh ¢. 2: 3 g. Young are weaned at ¢. 40 - 60 days. Lactating females are found May-August, depending on location. Young attain adult size in September. Average litter sizes vary across its distribution, with averages of 4 - 5 - 7 young, and a maximum of nine. The Least Chipmunk produces one litter per year, but females that lose a litter soon after the birth can have a second litter. In Michigan, some females potentially produce a second litter, butit is highly variable depending on location and year. Young reach sexual maturity at ¢. 8 months, but probably do not reproduce before one year of age.

Sciuridae