Virginia big-eared bat (Plecotus townsendii virginianus)
Federal Status: Endangered, November 30, 1979
Description: The Virginia big-eared bat is one of two endangered subspecies of Townsend’s big-eared bat (Plecotus townsendii); the other being the Ozark big-eared bat. This medium-sized bat (less than 0.5 ounce; 14 gram) is, as the name implies, characterized by large ears (more than 1 inch (2.5 centimeters) long) that are connected across the forehead. It has mitten-shaped glandular masses on the muzzle and elongated nostril openings.
Big-eared bats principally feed on moths but eat other insects as well. Flying along forest edges, they use their highly efficient sonar to detect insects in the air and on vegetation and capture them “on the wing.” These docile animals provide a valuable service by eating many harmful insects on their nightly excursions. In the early spring, females congregate in maternity colonies in the warm parts of certain caves and give birth to a single young. Most males are solitary during this time. The large offspring (25 % of the adult female’s weight) are capable of fight in about three weeks and are fully weaned at six weeks. Before the young can fly, the females leave them in the cave while they forage, returning periodically to allow the young to suckle. Virginia big-eared bats hibernate in the cooler, well-ventilated portions of caves during the winter and may lose half their autumn body weight before spring.
Habitat: The non-migratory Virginia big-eared bat inhabits caves year-round. These caves are typically located in karst regions (landscape characterized by limestone caves and sinkholes) dominated by oak-hickory or beech-maple-hemlock forest.
Distribution: The Virginia big-eared bat is known from parts of western North Carolina, eastern Tennessee, southwestern Virginia, eastern Kentucky, and southern West Virginia.
Threats: The major causes of the species’ decline are loss of habitat, vandalism, and increased human visitation to maternity roosts and hibernacula. Virginia big-eared bats are extremely sensitive to human disturbance. Even slight disturbances can cause adults to abandon caves, abandon young, and force bats to use valuable energy reserves needed to survive hibernation.
Critical Habitat: Critical Habitat for the Virginia big-eared bat was designated on November 30, 1979. For specific information on areas designated as Critical Habitat and the primary constituent elements defined for this species, please refer to the Federal Register notice (44 FR 69206-69208).
References:LeGrand, Jr., H.E., J.T. Finnegan, S.E. McRae, S.P. Hall. 2010. Natural Heritage Program List of the Rare Animal Species of North Carolina. N.C. Natural Heritage Program, Raleigh, NC.
U.S. Fish and Wildlife Service. 1984. Recovery Plan Ozark Big-eared Bat and Virginia Big-eared Bat. U.S. Fish and Wildlife Service, Twin Cities, MN.
For More Information on Virginia big-eared bat...
- U.S. Fish and Wildlife Service Environmental Conservation Online System
- Virginia big-eared Bat Recovery Plan
Sue Cameron, Fish and Wildlife Biologist, 828-258-3939 ext. 224
Species profile revised on October 4, 2011.