Volume 11
Issue 4

BCI joined with the Bucks County Conservancy, state wildlife biologists, and the landowner to halt plans to bulldoze the entrance to the Durham Mine, considered the most important bat hibernaculum in eastern Pennsylvania. This summer the mine received a protective gate, with funding from BCI, the Conservancy, and the landowner.

The Durham Mine opened in 1727 and was a rich source of iron ore for nearly two hundred years. Sometime after it was abandoned in 1912, bats began to move in. Four bat species* now rely on it as an overwintering site, and another, the small-footed myotis (Myotis leibi) is found there throughout the summer. By the 1930s it was recognized as an important winter hibernaculum. A large number of bats also use the mine as a rest stop on their way to other roosting sites.

Vandalism, however, has caused the bat population to decline. On the outskirts of Philadelphia, the mine has experienced a dramatic increase in human activity over the past few years despite the fact that it is on private land. A public outcry to close the entrance came after several recent incidents involving extensive rescue efforts and a great deal of media attention. The owner was concerned and considered sealing the mine for safety reasons.

Fortunately, the Bucks County Conservancy, a local conservation and preservation group, took the lead in trying to find alternatives. With the new gate, the mine is effectively closed to would-be explorers, yet still open to the bats. Bat populations are eventually expected to recover as has occurred at other gated sites.

* Little brown bats (Myotis lucifugus), northern myotis (M. septentrionalis), big brown bats (Eptesicus fuscus), and eastern pipistrelles (Pipistrellus subflavus).