Mammalian Pests

General Description
Mammals such as mice, rats, bats, raccoons, squirrels, etc., occasionally become pests. They can be very destructive to property and can carry a number of diseases. Extreme care must be taken when dealing with mammalian pests. Some species are protected by law and permits or specialty licenses from the state Department of Natural Resources or U.S. Department of the Interior are required to remove or eradicate them. Diseases such as histoplasmosis and raccoon roundworm also can be acquired from pathogens found in the pests’ fecal matter. Thus the proper cleanup of feces can be just as important as eradicating the pest itself. Parasites that transmit disease and live in/on the pests themselves, such as fleas on rats that carry plague and typhus, can be fatal to humans, therefore nesting materials must be removed with care.

Always wear intact rubber or plastic gloves when removing dead rodents and when cleaning or disinfecting items contaminated by rodents. Soak or spray dead animals with a disinfecting solution (three tablespoons of bleach per gallon of water, or a commercial disinfectant containing phenol) until thoroughly wet, then place in a plastic bag. If possible, use a shovel to pick up and dispose of dead animals into tight-sealing plastic bags. The bag should be sealed and placed inside a second bag before discarding in trash containers with tight-fitting lids. After handling dead animals, clean contaminated objects and thoroughly wash gloved hands using a general household disinfectant or soap and water. Remove gloves and thoroughly wash your hands with soap and water.


General Control
Exclusion is the best way to control most mammalian pests. Seal any openings larger than one-fourth of an inch to exclude them. Openings where utility conduits enter buildings should be sealed with metal or concrete. Equip floor drains and sewer pipes with tight-fitting grates having openings less than one-fourth of an inch in diameter. Doors, windows and screens should fit tightly and chimneys should be capped. Soffits should be inspected and maintained in good repair.

Poor sanitation and the presence of garbage help mammalian pests survive in residential areas. Good sanitation will effectively limit the number of mammalian pests that can survive in and around facilities. This involves good housekeeping, proper storage and handling of food materials and refuse, and elimination of shelter (harborage). Trapping mammalian pests can be very effective. If you want to trap mammalian pests other than mice or rats, please contact the Illinois Department of Natural Recourses for a permit and licensing requirements. Rodent baits should be used as a supplement to trapping. If there is a repetitive need for rodent control, it is likely that sanitation and rodent-proofing should be improved. Remember that rodent baits are poisons. Make sure they are registered with the U.S. Environmental Protection Agency and always follow the label instructions. If baits are used indoors, be sure they are labeled specifically for interior use. Rodenticide baits should be placed in areas inaccessible to children, pets and non-target organisms, and/or in tamper resistant bait stations.