Gray bats live in caves throughout the year, and are very particular in choosing a location to raise their young. Preferred caves are usually large, with a stream and a dome-shaped chamber that traps heat ath the ceiling where the bats cluster. Less thatn 5 percent of all caves in the gray bat's range are used for raising young bats. Indiana bats spend the winter in caves, and roost under the tree bark in summer. Gray and Indiana bats also are particular about caves for hibernation.
Gray bats require caves with deep vertical shafts which trap cold air.
Indiana bats also need cold caves. Missouri has more than 5,000 caves, but gray bats hibernate in only three of them. Only two dozen caves and a mine are used by hibernating Indiana bats. As these numbers show, if you own a cave used by one of these bats, you own a special cave. The Ozark big-eared bat has been reduced to less than 2,000 individuals.