House Mouse


House mice can squeeze through dime-sized cracks to gain entry into homes and buildings. Interestingly, the closer a house mouse lives in relation to humans, the darker the fur becomes.

Fast Facts

Color House mouse fur varies in color from light brown to black, while the underbelly typically appears beige.
Size The house mouse size ranges 5-7″ long, including the 3-4″ tail.
Appearance The tail of the house mouse bears some fur and has circular rows of scales.


House mice nibble on small amounts of food, eating at dusk and before dawn. They are omnivores with a diet focused on seeds, roots, leaves, and stems.

House mouse prevention and control - Batzner Pest Control in Wisconsin

Habitat & Nests

House mice thrive in various environments and are found in and around both homes and businesses, making their homes in wall voids, storage boxes, attics, barns, sheds, basements, crawl spaces, cabinets, warehouses and many other similar locations. During the fall and winter months, the colder temperatures drive these mice indoors, seeking shelter. House mice prefer to nest in dark, secluded areas and often build nests out of paper products, cotton, packing materials, wall insulation and fabrics. House mice are nocturnal, but they can be spotted during the day.


Mouse droppings are small pellets about a quarter of an inch long with pointed ends. The pellets are generally dark brown or black, though the color may vary depending on individual mouse diets. They are often deposited along areas of frequent activity, with the potential for thousands of droppings to accumulate over a short period of time, especially in the case of large infestations. Droppings from house mice, deer mice, and white-footed mice share characteristics and become hard and dry after a few hours.

Mice multiplication rate - Batzner Pest Control in Wisconsin

Life Cycle

Female house mice can produce between 5 and 10 litters per year, with each litter containing anywhere from 5 to 12 young. Pregnancy lasts up to 21 days until the hairless, blind, and helpless young are born.

Newborn house mice develop quickly, maturing to adulthood in just 6 to 10 weeks. Females are ready to mate about a month after birth, while most males reach sexual maturity two months after being born.

The average lifespan of a house mouse falls around one year in the wild and up to three years in captivity.

Signs of Infestation

Droppings & Sebum

Fecal pellets, urine stains, and grease trails may indicate a house mouse infestation.


Look for gnawing damage and tracks along baseboards.


Sounds of squeaking, rustling, scratching in walls, ceilings, attics, and crawlspaces, sheds or garages.


The most prevalent sign of a house mouse infestation is either seeing the rodents themselves or finding their droppings around the home.


House mice contribute to a variety of issues in and around the home. The rodents can spread diseases that cause varying levels of sickness in humans, as well as contaminate food with their droppings. Additionally, the pests are greedy feeders that consume large quantities of stored food and crops. House mice can also damage woodwork and building structures, as well as furniture, wiring, and even clothing, if left unchecked.

Prevention & Control

House Mouse Prevention

The best way to control a house mouse population is to prevent them from getting in unwanted areas. Simple preventative steps and minor repairs will block entry ways and prevent mice and other pests from coming inside.

Eliminate Entry Points
Mice can be very innovative in their attempts to enter a dwelling. They will move along the outside perimeter of a building until they find an opening or crack, and then sneak right in. Make house mouse infestations less likely by locating any openings around the home that are larger than 1/4″ and sealing the rodent-friendly entry points. Applying steel wool mixed with caulk around openings for pipes and wires may also help to keep mice away, as does the use of metal and concrete where necessary. House mice can gnaw through screens, rubber, and insulating foam. Review the areas listed below for places to prevent mice from entering:

  • Replace broken windows
  • Caulk around utility/service pipes
  • Weather strip around doors
  • Repair cracks or openings in the foundation
  • Screen all vents

Proper sanitation may help reduce the likelihood of a house mouse invasion; however, no amount of sanitation will keep mice away for long if food still remains available. Be sure to store food properly. Wash dishes and cooking utensils, and clean spilled food from food preparation areas and floors immediately. Also, dispose of any trash and clutter.

Regular Maintenance
Routine yard maintenance deters house mice. Cut overgrown shrubs and trim tree branches that hang over the roof; otherwise, mice could walk across the overhanging limbs and gain access to the house. Keep woodpiles away from the perimeter of the home and regularly clear debris from the lawn to avoid inadvertently giving pest rodents ideal places to hide.

House Mouse Control

Several baits and trapping tools on the market can help remove house mice from homes. However, if the infestation persists, or several invasions occur over a short period of time, count on a professional pest management service to take care of the problem knowledgeably and successfully.

Batzner Service Specialists are highly trained to conduct a thorough inspection to find evidence of mice. There are numerous methods available to eliminate mice, but in order to prevent more mouse problems, it is important to find the places where they’re getting in. Sanitation, exclusion, and population reduction are the keys to eradicating a mouse population. A Batzner Service Specialist will perform a service to eliminate the mice from your home and make sanitation and repair recommendations to help prevent future problems.

Regular inspections of your home by a pest control professional throughout the year is the best method to identify and prevent any issues with mice or any other pests. Pestfree365 provides regularly scheduled preventive services throughout the year.