Pest Identification And Information

Chipmunks

Chipmunks generally add to the enjoyment of being outside.  Their alert, playful and curious attitude makes them much appreciated by the public. Occasionally they become so numerous that they become pests.  They dig up newly planted seeds and bulbs, or attack cultivated fruits, seeds or stones.  Trapping, shooting, or poisoned grain most easily accomplishes control.  Keep in mind that that others in the neighborhood or immediate area might have a favorable opinion of chipmunks and not appreciate any measures to control them.

FACTS:

• Chipmunks are among the smallest members of the squirrel family.

• They are primarily ground dwellers, but climb trees and shrubs for food when necessary.

IDENTIFICATION:

Two genera are recognized in the United States.  The Eastern chipmunk is most common in North Eastern states from Canada to almost Florida, as far West as Michigan. The Western chipmunk can be found from Michigan to the Pacific, but is most common in the Rocky Mountains.

There is a close resemblance between the two species:

Eastern: 9 to 10.5 inches in length, 3 oz. in weight, and 3 dark dorsal stripes

Western: 8 to 9.5 inches in length, 2 to 2.5 oz. in weight, and 5 dark dorsal stripes

Chipmunks are sometimes confused with the 13 lined ground squirrel, which is a larger animal with thirteen alternating light and dark stripes.

BIOLOGY:

• Three to five young are usually born in May after a 31-day gestation period.
• By three months of age their mother sets the pups loose.

HABITS:

• While chipmunks do not go into complete hibernation like woodchucks and ground squirrels, they usually disappear by October into their deep burrows.  They apparently awake from a torpid condition at intervals to feed from caches in the burrows and may sally forth in mid-winter during warm spells. By mid-March they are very much in evidence. 

• The burrows are very lengthy, occasionally covering 30 feet or more, but there is no evidence of the excavated dirt around the burrow entrance.  It is probable that they carry this dirt in their cheek pouches and scatter it on the ground in the woods to make their burrow openings less conspicuous.

TREATMENT:

There are three essential ways to control chipmunks: trapping, shooting, poisoning. 

TRAPPING:

Trapping is the most preferred method where there are a small number of animals present.  Wind-up mousetraps (such as Ketch All’s made in Iowa) work very well and are considered safe.

Others like the #0 steel traps or the large wooden rat snap traps.  Place these near woodpiles etc. or near burrow entrances.  Be Very Careful and place traps so as to avoid injury to children, pets and other non-target species.                               

• Suggested bait materials include:

• Pumpkin or sunflower seeds

• Peanut butter

• Corn or rolled oats

• Nutmeats

Large baits (nutmeats etc.) should be tied to the trigger.  Rolled oats can be sprinkled on the trigger.

Quite commonly when frightened, they'll run up your drain spout as far as they can.  If you are prepared, you can trap them on their exit.

SHOOTING:

Where firearms can be used, a small gauge shotgun is preferred to a .22 rifle. Hunting is more effective in the early morning and late afternoon. This is not legal inside of city limits and presents many safety concerns.

POISON:

Poisoned grain is an effective control agent, but must be handled carefully to avoid danger to beneficial wildlife, children, pets and livestock. Make sure what you use is labeled for use on chipmunks.  This is usually used against large populations.

Tracks In Mud                    In Dust                                 Scat

The Western chipmunk could be considered a health hazard, being reservoirs of Rocky Mountain spotted fever, plague, tularemia and relapsing fevers.  Also, they may be involved in the spread of ticks and fleas.