The Indiana bat (Myotis sodalis) was listed as endangered in 1967. Indiana bats are vulnerable to disturbance because they hibernate in large numbers in only a few caves (the largest hibernation caves support from 20,000 to 50,000 bats). Other threats that have contributed to the Indiana bat’s decline include commercialization of caves, loss of summer habitat, pesticides and other contaminants, and most recently, the disease white-nose syndrome.
Indiana bats are found over most of the eastern half of the United States. Almost half of them hibernate in caves in southern Indiana. The 2009 population estimate was about 387,000 Indiana bats, less than half as many as when the species was listed as endangered in 1967.
Indiana bats are quite small, weighing only one-quarter of an ounce (about the weight of three pennies) although in flight they have a wingspan of 9 to 11 inches. Their fur is dark-brown to black. They hibernate during winter in caves or, occasionally, in abandoned mines. During summer they roost under the peeling bark of dead and dying trees. Indiana bats eat a variety of flying insects found along rivers or lakes and in uplands.
Specialized Ecological Services uses the latest Indiana Bat survey guidance provided by the USFWS.