The eastern chipmunk is the only chipmunk found in Connecticut. It is reddish brown in color with a single black stripe running down the center of its back. A white stripe between two black stripes runs down each side of its body from the neck to the base of the tail. The chipmunk has a white underside and a white stripe above and below its eyes. Chipmunks range in size from 8 to 10 inches long (including the tail) and weigh between 2 to 5 ounces. There is no difference in appearance between males and females.
The eastern chipmunk is found in deciduous forests, shrub habitat, forest edges, and suburban and urban areas where there is abundant cover to protect it from predators.
Chipmunks are omnivores (they feed on both plants and animals). Their diet includes seeds, nuts, berries, fruits, flowers, mushrooms, insects, worms, snails, frogs, bird eggs, and small birds.
Chipmunks mate twice a year from February to April and again from June to August. Males and females come together only to mate. Females raise their young alone. After a gestation period of 31 days, a litter of 2 to 6 young is born (some litters may be as large as 9 young). Hairless, blind, and helpless, newborn chipmunks are about the size of a bumblebee. The young remain underground in the burrow for about 6 weeks. After approximately 8 to 10 weeks, they are fully independent and leave the female. Chipmunks reach sexual maturity in about 1 year.
Chipmunks are most active in the early morning and late afternoon. Although they can climb trees, they spend most of their lives on the ground or underground in burrows that may reach 30 feet long and 3 feet deep. These burrow systems include nesting chambers and storage rooms for nuts and seeds that provide chipmunks with food throughout the winter. The burrow entrance usually measures two inches in diameter. Chipmunks remove the fresh dirt from the opening to avoid being conspicuous to predators. They fiercely guard their territory from other chipmunks.
Beginning in late October, chipmunks sleep for long periods throughout the winter but they do not hibernate. They occasionally wake to snack on stored nuts and seeds and may even come outside for brief periods of time on warm winter days.
Chipmunks are very vocal and make a variety of noises. They get their name from the “chip, chip” sound they make.
An enormous amount of food can be held in their cheek pouches, which can stretch to three times the size of the head. When gathering large nuts, chipmunks bite off sharp edges and stems.