Data Sheet

Pronunciation: core-ee-no-rine-us raff-a-nesk-kee-eye

Rafinesque’s big-eared bats are known to form nursery colonies in large hollow trees. Hollow tree roosts provide stable internal environments, protection from predators, and often contain well-insulated areas that form hot-air traps essential for rearing young. These bats range throughout the southeastern United States from southern Virginia south and west to eastern Texas and northward along the Mississippi River valley to southern Indiana. Their range most closely approximates the historical range of great cypress swamps, indicating that they may have formed a traditional reliance on these areas as roosting and foraging sites.

As swamplands have been drained and trees have been harvested, these bats have apparently moved their maternity roosts into old buildings or attics. Rafinesque’s big-eared bats are slow, agile flyers and appear to forage on a wide variety of small nocturnal insects, especially moths. They hibernate near their summer foraging grounds in old mines, caves, and cisterns.

Though widespread in the eastern U.S., this bat is nowhere near as abundant and population levels appear to have declined in the past century due to loss of summer roosting or foraging habitat and/or disturbance at winter hibernacula. Rafinesque’s big-eared bats are at special risk where they form nursery or hibernation colonies in caves susceptible to recreational disturbance and in abandoned mines slated for closure or reclamation.