Vespertilionid Bats: Vespertilionidae

Physical characteristics: Similar in appearance to the big brown bat, this species is a bit smaller. Its body length averages 3.1 to 3.7 inches (20 to 27 centimeters) with a tail a little less than half that size. It weighs 0.2 to 0.5 ounces (6 to 14 grams). The little brown bat is light to dark brown above with a lighter belly.

Geographic range: This bat lives in Canada, the United States, and Mexico.

Habitat: When they aren't flying in search of food, they do their summertime resting in tree hollows, underneath bark, or in barns, attics, and other such structures. During winter, they typically hibernate in caves.

Diet: Their diet consists mainly of flying insects.

Little brown bats fly in search of food, mainly flying insects. (© Joe McDonald/Corbis. Reproduced by permission.)

Behavior and reproduction: They mate in the late summer to early fall. The females typically have just one pup in late spring or during the first half of summer. The young grow quickly, but don't mate until at least the following year.

Little brown bats and people: Like many other insect-eating bats, the little brown bat helps to control pest insect populations.

Conservation status: This bat is not threatened. ∎