Controlling Nuisance: Chipmunks
Missouri Department of Conservation
U.S. Fish and Wildlife Service
Chipmunks are small ground-dwelling rodents with distinctive stripes on their rusty-red to chestnut-brown fur. Five dark-brown stripes line the back — one down the backbone from the neck to rump, two on each side from shoulder to rump. A creamy-buff stripe separates the dark side stripes. Mature chipmunks are nine to 10 inches in length and weigh about three ounces. The flattened, well-haired tail is roughly one-third the animal's total length.
Chipmunks have forefeet adapted for holding and eating food while they sit upright. Their heads are blunt and squirrel-like and have unique furred cheek pouches in which they carry food and other material. The front teeth are chisel-shaped. Chipmunks may range over an acre, but their individual territories often are much smaller.
Chipmunks are omnivorous; they feed on both plants and animals. Plant material such as acorns, hickory nuts, beechnuts, cherry seeds, serviceberries, raspberries, dogwood seeds, corn and plant bulbs are favorites. The main animal foods are birds' eggs, insects, snails, and occasionally mice and young birds.
Chipmunks spend much time in late summer and fall gathering and storing food. Hard foods are stuffed into their cheek pouches and stored in food caches. They climb shrubs and trees to look for food and to escape enemies.
In their woodland habitat, chipmunks may compete for food with other mast-eating animals. When storing excessive amounts, they may limit availability of seeds that might be used by other wildlife, or that would germinate into new plants.
When chipmunks move into an urban setting, they may conflict with man. In their normal activities, they may dig seeds from the garden, feed on flower bulbs and burrow into lawns, especially near dry rock walls. In lawns, the two- to three-inch diameter burrows descend almost vertically. Burrow openings are cut neatly through the turf and lack excavated soil at the entrance. If the homeowner places a higher value on his garden, lawn, or flowers than on seeing chipmunks, control measures are needed to offset the conflict.
Homes with wooded lots, thickets of ornamental shrubbery and dry rock walls are attractive to chipmunks. This habitat can be made less attractive to the animals by altering the pattern of natural and ornamental plantings. However, most people value their trees and shrubs too highly for drastic modification of the landscape and may opt to tolerate the chipmunks as a part of the natural community.
Though chipmunks are protected, they may be trapped or shot when they cause property damage.
Live trapping with small commercial or homemade box traps can reduce their numbers. Once trapped, they should be released at least a mile from the capture area.
Rat-sized snap traps are effective, but they kill the animals. Baits attractive to chipmunks include peanut butter, nut meats, sunflower seeds and rolled oats. Place either type of trap in areas where chipmunks travel or feed.
Chipmunk numbers can be reduced locally. However, new animals may move into vacated habitats. Thus, chipmunks can seldom be eliminated from an area unless their living conditions are radically changed.
Chipmunks will occasionally enter homes where they are generally more bothersome than destructive. Their entry can be prevented by closing holes in foundation walls and by screening windows, vents and other ground-level openings.
Pesticides are not suggested for use to control chipmunks.