Evening bats (Nycticeius humeralis) are native to an area that spans from the Great Lakes region of the United States, as far east as North Carolina, south to Florida, and as far west to Texas. Evening bats are social and live in small colonies that are made up of a few dozen individuals. The males and females have different yearly living patterns. The males will remain in the southern parts of their range and the females will migrate north to form maternity colonies in the spring.
Evening bats are a dark colored bat, dark brown to almost black in color. They range in size from 3 ½ inches to 4 ¼ inches in length and a wingspan of 10 to 11 inches wide. They also do not reach a weight of more than 14 grams. These bats are not cave dwellers. They will roost in tree hollows, under the bark of dead trees, or in man-made structures like buildings, under bridges, and in old barns.
Evening bats will mate in the late summer or fall and then the females will migrate north to form their maternity colonies. The pups are born in the late spring or early summer in litters that average in size of 2. They fly by 3 weeks old and are completely weaned between 6 and 9 weeks after birth.