The eastern chipmunk is a small, ground-dwelling squirrel with conspicuous lengthwise stripes on the back, sides, and cheeks. The tail is well haired but not bushy, is somewhat flattened, and is shorter than the body. The background color of the upperparts is a grizzled reddish brown, grading into rusty on the rump and flanks. There are 5 dark brown to blackish lengthwise stripes from shoulders to rump, with a buff to whitish band between the two stripes on each side. The belly and sides are buff to white. The tail is blackish above and rusty below, with a narrow white or yellowish fringe. Chipmunks make a variety of calls, especially “chips” and a soft “cuck-cuck.” They make a trilling “chipp-r-r-r-r” when surprised.
Similar species: The thirteen-lined ground squirrel has 13 alternating light and dark stripes running along the back and sides from head to rump: the light stripes are yellowish to white, and the dark ones are blackish to reddish brown, broken by a series of light spots. That species is declining and occurs in localized populations mostly in northwest Missouri.
Total length: 8–12 inches; tail length: 2½–4½ inches; weight: 2–5 ounces.
Although they range widely in Missouri, chipmunks are most common in the Ozarks.
Habitat and Conservation
Chipmunks prefer timber borderland rather than deep forests. They are solitary and territorial. They select wooded banks, log heaps, stone piles, broken rocky ridges, or rubbish heaps as sites for their tunnels and nest chambers. Occasionally they live around city homes and farmhouses, where they live in shrubbery, stone walls, and old outbuildings.
The primary foods of chipmunks are nuts, seeds, and berries, particularly hickory nuts, acorns, beechnuts, hazelnuts, and walnuts, plus corn and wheat. The first part of the scientific name, Tamias, is the Greek word for “a storer,” which describes the food-storing habit of this animal. Chipmunks stuff nuts and seeds into their cheek pouches and transport them to their burrows for storage. The storage chamber in a chipmunk burrow may contain up to half a bushel of nuts and seeds. Chipmunks relish but do not store perishable foods such as mushrooms and many types of berries. Occasionally chipmunks eat insects and their larvae, millipedes, earthworms, slugs, snails, and other small animals.
Common in appropriate habitats. The name "chipmunk" apparently began as a Native American word, "ajidamoonh" (Ottawa) or "ajidamoo" (Ojibwe). English speakers gradually transformed it into "chipmunk," with the "chip" linked to the sharp "chipping" voice of this rodent.
Breeding begins in spring when hibernation ends. Most young are born in April and May, and in July and August. Females have 1 or 2 litters a year. The gestation period is 31 days. Litters contain 1–8 young, but usually 4 or 5. The young start exploring aboveground when 5 or 6 weeks old. Different chipmunks hibernate more or less than others, with some becoming completely dormant in winter, some being active during mild periods, and others being active all winter. Hibernation ends by early March. An eastern chipmunk can live up to 5 years in the wild.
These beautiful and exquisite little mammals have a high aesthetic value to us because unlike most mammals, they can be easily observed in daylight. If the digging of chipmunks is causing problems, control measures may be taken in accordance with The Wildlife Code of Missouri.
The tunneling of chipmunks aerates the soil and checks rain and snow runoff. Their food habits influence the growth of certain plant species and act as a partial check on insect populations. Their bodies furnish food for many carnivorous animals. Observers have noted that birds may be attracted to a singing chipmunk.
Signs and Tracks
- ¾ inch long
- 4 toes.
- 1¼ inches long; but only 1/2 to 7/8 inch long when heel does not show
- 5 toes
- Back of heel often indistinct or not leaving a print.
- Length between bounds is 6–12 inches.
- Tracks in clusters of 4, with front feet positioned behind and between hind feet, and one front foot usually behind the other.