The Indiana myotis is a medium-sized bat closely related to the little brown myotis, gray myotis, and northern long-eared myotis. Indiana bats have brownish-gray fur with cinnamon overtones. The ears and wing membranes are blackish-brown. Indiana bats are difficult to distinguish from our other myotises (mouse-eared bats). The main identifying feature of the Indiana myotis is a distinct keel on its calcar (the cartilaginous supporting structure on the rear edge of its tail membrane). Other clues include its general coloration and the wing being attached along the side of the foot, all the way to the base of the toes.
Length: 2 inches; wing span: 8 inches; weight: 1/4 ounce.
More than 85 percent of Missouri's total population of Indiana myotises hibernate in only eight specific locations, three of which are located in Shannon, Washington, and Iron counties of Missouri. Summer roosting Indiana myotises have been recorded in northern Missouri.
Habitat and Conservation
Indiana myotises need cool caves with stable temperatures of around 40F and relative humidity of 66–95 percent. Of Missouri's 6,500 known caves, only 27 ever had sizable populations of this species. Conservation efforts include avoiding disturbing hibernating bats and nursery colonies, maintaining cave habitats, improving streamside habitats, and reducing use of pesticides. White-nose syndrome is a grave concern; it caused an approximately 10 percent annual decline between 2006 and 2009.
BATS AND COVID-19: There is no evidence that Missouri bats have COVID-19 (SARS-CoV02), the virus that is causing the human pandemic. All viruses that have been identified in U.S. bats are alphacoronaviruses, while COVID-19 is a betacoronavirus. MDC, the U.S. Fish and Wildlife Service, and the Association of Fish and Wildlife Agencies are concerned about the possibility of bats contracting the COVID-19 virus from infected humans. Until more information is available, no activities that result in the direct interaction with live wild bats or with MDC-owned caves are permitted under existing or new 2020 Wildlife Collector Permits at this time. To protect bats, people are advised to not interact with them.
Indiana myotises are insectivores, eating primarily moths and beetles but also true flies and aquatic insects such as caddis flies and stone flies. These insects are captured and eaten "on the wing."
Listed as Endangered by the Missouri Department of Conservation and by the U.S. Fish and Wildlife Service.
Indiana myotises summer along streams and rivers in north Missouri, raising their young under bark of certain trees. They hibernate through the winter in caves and abandoned mines (never in houses) in the Ozarks. Females enter hibernation in early autumn, shortly before the males. This species hibernates in clusters of several hundred to several thousand. They emerge from hibernation in early spring and begin migrating to their summer roosting and foraging areas.
Myotis bats together consume hundreds of tons of flying insects per year, including many crop pests and other troublesome insects. Meanwhile, pesticide use and habitat disruption by humans negatively impacts the populations, and possibly the existence, of these agile little flyers.
Bats not only control populations of night-flying insects but also play an important role in the cave ecosystems that most of us rarely see or even think about. Yet healthy caves and springs harbor many unique life forms and are an important Missouri natural resource.