Identifying a deer mouse involves noting several vital physical characteristics. Look for the distinctive bi-coloured pattern of its fur—darker on the back with a white underbelly and feet. This coloration is one of the most distinguishing features. Deer mice have large, black eyes and proportionately large ears, which are more prominent than many other mouse species. Their tails are long, often as long as their bodies, and are bi-coloured, darker on top and white underneath. The body length of an adult deer mouse ranges from 7 to 10 cm (2.8 to 3.9 inches), with the tail adding length. When identifying a deer mouse, consider its habitat, as they are commonly found in various environments, including forests, grasslands, and areas near human dwellings. Observing behaviour can also aid identification; deer mice are nocturnal and exhibit agile climbing and jumping abilities.