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eastern red bat

eastern red bat (Lasiurus borealis)
Photo © Michael Durham

Features and Behaviors

The eastern red bat is three and three-fourths to four and three-fourths inches in length. It has rust-colored fur with white at the tip. Its large, wide tail is furred on the top, and its hind feet are furred, too. The shoulder has a white patch. The tragus is less than half the length of the ear.

The eastern red bat may be found statewide in Illinois. This mammal lives primarily in trees, bushes, shrubs and weeds but may occasionally be found in attics or caves. Its wintering roost sites are not known. The eastern red bat is an insectivore that feeds from dusk to dawn. This bat is fairly tolerant of cold. Mating occurs in the fall and spring. Those females that mate in the fall store sperm in the uterus until spring, when it is used to fertilize the eggs. The gestation period is about three months. Two, three or four young are born to a female in May or June. The female forages without taking her young with her.

Illinois Range


​Kingdom: Animalia
Phylum: Chordata
Class: Mammalia
Order: Chiroptera
Family: Vespertilionidae

Illinois Status: common, native