Mice

Pestgon FactSheet

HOUSE MOUSE (Musmusculus)

Description:
The house mouse is a small slender rodent with a slightly pointed nose and relatively large ears and small black, bulging, eyes. They are generally grayish brown with a gray or buff belly and weigh about 1/2 ounce. An adult is about 5-1/2 to 7-1/2 inches long, including the 3- to 4-inch tail. Mice are active mostly at night, but they can be seen occasionally during daylight hours. House mice are considered among the most troublesome and economically damaging rodents in the United States.

Biology:
Native to Central Asia, the house mouse arrived in North America on ships with settlers from Europe and other countries. The house mouse often lives in close association with humans. They are more common and more difficult to control than rats. Mice are very prolific. A female may have as many as 12 litters in a year, of about 5 or 6 young. Although house mice usually prefer to eat cereal grains, they will sample and contaminate many different foods.

Mice naturally live outdoors. However, at the beginning of cooler weather in the fall, mice will seek shelter and food inside homes and commercial buildings and any other structures. They can squeeze through openings slightly larger than 1/4 inch. Mice are also excellent climbers and are able to run up any rough vertical surface and then travel horizontally along wire cables.

Economic Impact:
The economic impact of mice can be very serious, but they do not cause the same degree of health and economic problems as rats. They do, however, contaminate and destroy many stored food products with their droppings. Mice also commonly destroy paper goods, woodwork, furniture, upholstery, and clothing. It is known that mice contribute to the spread of diseases such as murine typhus, rickettsial pox, tularemia, food poisoning (Salmonella), and bubonic plague. The presence of mice is especially troublesome in an office environment.

Effective control involves sanitation, exclusion, and population reduction. Pestgon recommends preventive measures such as, sanitation and exclusion as the first line of defense. Exclusion is the most successful and permanent form of house mouse control. When a mouse infestation already exists, trapping or baiting is almost always necessary.

Additional Links:
http://www.ipm.ucdavis.edu/PMG/PESTNOTES/pn7483.html