Threatened and endangered species may reside in or around AML affected lands and waters. This is especially true for bat species. Adits, entrances to mines, often provide bat habitats. In many instances, the bats are displaced from their preferred roosting sites by encroaching human development and wanton destruction. Although mines are human-made, as we disturb, alter, or destroy natural habitats for bats, human-made habitats become critical in the conservation of bat species.
Bats are the major biological controllers of nighttime flying insects and play an important ecosystem role. Insects controlled by bats include many agricultural and forest pest insects. For example, a single little brown bat can catch 600 mosquitoes in just one hour. In the southwest United States, many desert plant species are dependent on pollination by bats.
Bat grates and cupolas are cost-effective closure methods that protect and promote bat habitat by allowing bats to pass in and out of a mine while blocking human entry. BLM installs bat grates/cupolas when mine openings are determined to be beneficial as habitat for bats.