Mating Habits of Chipmunks

Generally, chipmunks are loners, only coming together in the spring to mate. In April, mature male chipmunks are ready to mate two weeks before females and sometimes compete with each other for females. Males often travel long distances to check out female territories to make sure they are ready to mate. Some males mate with several females. Species like the eastern chipmunk and Siberian chipmunk go through two different breeding periods, in early spring and then again in late summer. Chipmunks communicate to members of the opposite sex by vocalizing chirps, croaks and other verbal signals.

Chipmunks develop in their mother's womb for at least a month. Litter sizes vary. For example, least chipmunks have a litter with two to six young, while Siberian chipmunks have three to eight young. Newborn chipmunks are born hairless and don't open their eyes for the first month of life. In species such as the eastern chipmunk, females provide all of the care to their litters. This care is extensive and involves feeding, protecting and grooming for at least 60 days, which is when the chipmunks born in spring are old enough to go out on their own in August. In other species like the least chipmunk, males play a role in raising offspring by providing protection and possibly bringing food to the nest.

To prepare for the upcoming winter, chipmunk offspring leave their mother's care to search for their own territory and collect food like berries, insects, birds' eggs, snails and seeds. Chipmunks search for food on the ground, but they will occasionally climb trees. Food is gathered until late October, when the chipmunks are finished filling their tunnels and burrows with food. Chipmunks don't truly hibernate. Instead, they suppress their activities to minimally use their metabolism. This is known as torpor. The chipmunks rest over the winter, occasionally eating from their food reserves.

Some chipmunk species, like the Siberian chipmunk, mate and produce a second litter in late summer. This litter develops just in time to collect food and take shelter during the winter. At 10 months old, around the month of February in late winter, chipmunks born the previous spring are sexually mature. In species like least chipmunks, mature females are larger than males. Mature males are larger than females in species like the eastern chipmunk. Chipmunks typically live for between two and 10 years in the wild.