Wildlife Damage Management, Internet Center for


Date of this Version

October 2000


When a house bat colony (primarily Myotis lucifugus) is excluded from a traditional maternity roost, surviving bats add to nearby roosts or access new roosts in other buildings. To prevent this and the potential for attendant nuisance, and to conserve bats, the Pennsylvania Game Commission recommends using one or more bat boxes to attract the displaced colony. The "standard-sized" bat box used in Pennsylvania will house up to 250 little brown bats. This reactive technique has proved useful for managing single, small colonies (< 1,000 bats) in rural areas. We are, however, trying a different, proactive technique to manage large colonies or multiple colonies in a community. Newport, PA, for example, has multiple colonies in buildings within 200 meters of riparian habitat along the Juniata River. Over 7,000 bats were counted exiting a single building. To begin the process of managing these bats, the high school conservation club and town leaders were engaged and presented information about the value of bats. Programs were also presented to a school assembly and to the community. As a result, the conservation club was provided with a site at the community's water treatment plant to erect a bat condo. This site is within 1 km of at least 2 large bat colonies in old buildings. The condo is a 2.4 m square box on posts. It's 2.4 m tall with its bottom 3 m above the ground. Inside, 80 sheets of plywood provide roosting crevices for at least 2,500 bats. Supervised by the Wildlife Diversity Section of the Game Commission, the condo was built in late spring, 1999. A chain-link fence helps protect it from vandalism.