The mouse is a rodent that measures between 13 and 19 cm. The back of the mouse is usually dark gray or brown in color, while its abdomen is paler. Like the field mouse, the mouse lives in the fields, but does not dig holes. It appropriates the burrows of other rodents: rats and field mice. The mouse can penetrate the structure of buildings through an opening of only six millimeters. It makes its nest in floors, false ceilings, under shelves at the bottom of cabinets, in cardboard boxes, food containers and in some insulation materials.

The mouse can travel from one floor to another through the pipes. It feeds on meats, grains, flour, rice, vegetables, fruits, sugary and protein foods such as nuts, peanut butter, and animal feed. The mouse can have about 12 litters of five pups in its lifetime. Babies reach maturity in 35 days and can reproduce as early as three months. The mouse lives on average between 15 and 18 months.