4954 N. Shamrock Place, Tucson, AZ 85705

House Mouse

Mus domesticus

House Mouse

Physical Features

Body 2-4 inches in length, equally long tail, moderately sized ears, grayish-brown with a gray or buff belly, and normally weigh .5 to 1 ounce.

Life Cycle

Live Young
Mice may breed year round indoors producing 5-10 litters compared to outdoors where they breed less often. After an 18 to 21 day gestation period, the female delivers a litter of 2-13 young. The young are naked and have their eyes closed. After 2 weeks, they are covered with fur and their eyes and ears are open. They begin to make short trips from the nest foraging for food. At 6-10 weeks they are sexually mature. The nest is often shared.  Mice will travel 10-30 feet or more from their nest when searching for food or water. They can live long periods without water obtaining water from their food sources.


  • Diet: Seeds. They are erratic feeders taking small bits at a time from different areas. Consume about 10% of their body weight per day.
  • Activity: Nocturnal especially the time following sunset and prior to sunup.
  • Preferred Climate: Depends on species but prefer constant temperatures found indoors.
  • Defense: Speed and size. Rely on smells and pheromones.
  • Cautions: Rapidly reproduces
  • Home Invasion: House mice will nest in secluded areas within a structure or in the ground near structures or food sites.

Helpful Hints

  • Thorough sanitation practices to eliminate food sources
  • Recommend regular pest control service plan.

Interesting Facts

Mice detect new items placed in their pathways, but unlike rats, they do not shy away from these items.


Hantavirus is a virus found in rodent urine, saliva and feces. It will infect lungs and can cause HPS (Hantavirus Pulmonary Syndrome). The first symptoms will begin about two weeks after exposure to mice and will include:

  • high fever
  • body aches
  • chills
  • trouble breathing
  • abdominal pain
  • lower back pain

A couple of days after these symptoms start, severe respiratory distress will begin and lungs will shut down. HPS is very serious but with advanced medical care, most people do survive the infection.