Effective mouse control involves sanitation, mouse proof construction and population reduction. The first two are useful as preventive measures. When a mouse infestation already exists, some form of population reduction is almost always necessary. Reduction techniques include trapping and poisoning.

Sanitation. Mice can survive in very small areas with limited amounts of food and shelter. Although good sanitation will seldom eliminate mice, poor sanitation is sure to attract them and will permit them to thrive in greater numbers. Good sanitation will also reduce food and shelter for existing mice and in turn make baits and traps more effective.

Mouse-Proof Construction. The most successful and permanent form of house mouse control is to “build them out” by eliminating all openings through which they can enter a structure.

Seal any openings larger than 1/4 inch to exclude mice. Steel wool mixed with caulking compound makes a good plug. Patching material needs to be smooth on the surface to prevent mice from pulling out or chewing through the patching compound. Seal cracks and openings in building foundations and openings for water pipes, vents and utilities with metal or concrete. Doors, windows and screens should fit tightly. It may be necessary to cover the edges with metal to prevent gnawing. Plastic sheeting or screen, wood, rubber or other gnawable materials are unsuitable for plugging holes used by mice

Traps. Trapping is an effective control method. When only a few mice are present in a building, it is usually the preferred control method.

The simple, inexpensive wood-based snap trap is effective. Bait traps with peanut butter, chocolate candy, dried fruit or a small piece of bacon tied securely to the trigger. Set them so that the trigger is sensitive and will spring easily. Set traps close to walls, behind objects, in dark corners and in places where evidence of mouse activity is seen. Place them so that mice will pass directly over the triggers as they follow the natural course of travel, usually close to a wall.  Use enough traps to eliminate the rodents quickly. (Using too few traps is a common error by individuals attempting to control mice.) Mice seldom venture far from their shelter and food supply, so place traps no more than 10 feet apart in areas where mice are active. Leaving traps unset until the bait has been taken at least once (prebaiting) often increases the success of trapping.

Poison Baits (Rodenticides). Rodenticides are poisons that kill rodents. They can be purchased in hardware stores, feed stores, discount stores, garden centers and other places where pesticides are sold. Do not buy unlabeled rodent baits from street vendors or other uncertain sources. Do not purchase baits that have an incomplete label or one that appears to be “homemade.”