Males tend to be active longer into the fall, but are in hibernation by late November. Sperm is stored during the winter and females become pregnant soon after emergence in late March and early April. Young are born in June and July. Colonies are usually located along streams where the bats forage for flying insects. Not much is known about male roosting behavior.
Young bats are able to fly approximately a month after birth.
Low cave temperatures allow the bats to maintain a low metabolic rate throughout hibernation. Only a small percentage of caves meets the specific conditions required by Indiana bats. During the summer, they can be found under bridges, in old buildings, under tree bark, or in hollow trees. Streams lined with large, overhanging trees are preferred. The Indiana bat is found primarily in the midwestern and eastern United States.