Cornell Cooperative Extension and the Utah University Extension offer the following tips for discouraging mice from weaseling their way inside:
* Seal openings to the house larger than one-quarter inch with such materials as mortar, sheet metal or heavy-gauge hardware cloth.
* Keep closed doors to houses, garages, barns and other structures.
* Store bulk foods, pet food, bird seed, garbage, compost and recyclables in rodent-proof containers made of metal, glass, ceramic or heavy-duty plastic with tight-fitting lids. Mice can chew through wood, aluminum siding, plastic garbage cans, Sheetrock and lead or copper pipes!
* Promptly clean up crumbs and spills.
* Keep stored items off the floor, reduce clutter and remove cardboard boxes if possible.
* Clean garbage cans and chutes regularly.
* Refrigerate uneaten pet food instead of leaving it out in food bowls.
* Elevate outdoor compost piles or enclose them with quarter-inch wire mesh.
* Keep birdfeeding areas clean of spilled seed.
* Monitor woodpiles for mouse shelters in gaps and hollow logs, especially before bringing wood in the house.
* Move firewood, garbage cans, debris piles, discarded appliances and vehicles away from the house. For easier inspection, maintain a 1-foot-wide gravel border that’s free of vegetation around the foundation or keep plants closely trimmed.
* Remember that thick vegetation, debris like garbage and leaves, clutter like bricks, lawn furniture and discarded appliances, and piles of wood or rocks are favored by mice.