Physical Characteristics of Rats and Mice

Posted on December 28, 2019

There are over 70 species of mice and rats widely distributed across North America. The house mouse (Mus musculus), Norway rat (Rattus norvegicus) and roof rat (Rattus rattus) species are in the Muridae family, which is the largest family of rodents and mammals in the world.

House mouse: Small head, small feet, pointed snout, large ears with some hair. These mice have a light brown body with some gray shading and a dark tail. Adults weigh 0.5 ounces (15 grams). The mice droppings are shaped like rods.

Norway rat: Heavy and thick body, blunt snout, and short ears with dark hair. These rats have a brown body with black shading and a shaggy coat. Their tails are dark on top and pale underneath. Adults weigh 11 ounces (300 grams). Their droppings are shaped like capsules.

Roof rat: Light and slender body, pointed snout, large ears with no hair. These rats have a gray body with black shading and a smooth coat and a dark tail. Adults weigh 7 ounces (200 grams). Their droppings are shaped like spindles.

Physical Characteristics of Rats and Mice

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