Audubon Gates

The historic Philadelphia area home of James Audubon lies atop a hill rich in copper. This copper deposit was mined extensively, the ore removed via vertical shafts. Two drainage tunnels were blasted out of the hillside to drain groundwater into a nearby creek. These two drains are the only entrances remaining. Due to collapse very little of the mine is accessible to humans, but bats may have access to the main adits.

Prior to our work on site only one of the drainage tunnels was open, the other having been blocked by debris slumping off the hillside. In a effort to improve the habitat (The mine is too warm for most bats, if the two entrances were open and connected cross currents might have lowered the temperature to a more suitable range.) the second entrance was reopened. Unfortunately the reopened entrance was sumped (flooded to ceiling) approx. 150 feet in. However, the gates do preserve the historic nature of the site, and there is a entrance room that might be suitable for the smallfooted bat (that species prefers crevices in cold entrance areas). The accessible part of the mine does support a small hibernating population of bats.