Don’t Let Mice Ruin Your Winter

Mice are a common household pest in Utah. The house mouse does not hibernate, and as temperatures drop in the fall and early winter, they migrate into homes seeking food, warmth, and shelter. People do an excellent job providing these basic needs to mice. Mice investigate house perimeters for warm air and food odors leaking out from any opening. Mice only need a hole about the size of a #2 pencil (1/2” high by 3/8” wide) to gain access to your home. They are unwant­ed visitors capable of spoiling food with fur, urine and feces, and transmitting disease. A few important steps can minimize mice in the home.


Search the perimeter of your house and look for possible entry points. All holes should be sealed using appropriate materials: caulk, sealant, and/or copper mesh.  Thresholds and door sweeps are the primary area of weak­ness in your house’s security. Replace thresholds and/or door sweeps with high-quality options such as a thick, brush-style door sweep. During installation, check to see if the eraser side of a #2 pencil will fit through any gaps and fix if neces­sary. Installing door sweeps will also keep out other pests, in addition to reducing heating and cooling bills.


Mice need three things: food, shelter, and warmth. Focus inspections in places where food is stored, as well as under, behind, or in appliances that generate heat (anything with a motor and the stove/oven). Also look in areas that are secluded, dark, and shadowy, especially corners.  Look for fecal pellets, urine droplets, build-up of brown grease (sebum) along frequently traveled routes, gnaw marks, and tiny hairs in feces or stuck to openings in walls where mice squeeze through. You can also look and listen for mice activity. Again, think food, shelter, heat, shadows, and corners.


Sanitation is pest management. Eliminating food sources through proper food storage in mouse-proof containers will take its toll on mouse populations. Good sanitation and food stor­age stress mice, causing them to have fewer offspring, and to travel farther to find food. Remember, mice want food. Don’t let them have it!


The most effective and humane traps are the standard snap-traps. Pregnant females make many trips per night to collect nesting materials like string. If you can trap one pregnant female, you have effectively eliminated at least one, and maybe up to 7 or more mice at once.

Place traps in high-activity areas. These are places where mice travel and feed. Position traps against walls with the cocked trigger facing the wall.