Deer mice are the prototype for "field mice" with large, bulging eyes, big ears, a bicolored pattern and a long tail. They are larger than the harvest mice, but noticeably smaller than woodrats and cotton rats. The deer mouse is about 148-200 mm (seven in.) long, including the tail.

Deer mice are commonly found in California and Mexico. Throughout their range, they are found in nearly all ecological communities and life zones from the desert floor to the high mountains. They can be highly abundant, numbering as many as ten per acre.

WARNING

Deer mice may be carriers of Hantavirus. When present, this virus is spread through the rodent's urine and feces. Although the mice do not become ill from the virus, humans can become infected when they are exposed to contaminated dust from the nests or droppings. We are advised not to camp or sleep where mouse droppings are abundant, and to clean indoor areas where they live using appropriate precautions.