Bracken Cave

Bracken Cave, the maternal home to some 20 million Mexican free-tailed bats, was a guano-mining site for over a century, providing fertilizer, and during the Civil War, saltpeter for Confederacy gunpowder. In 1992, Bat Conservation International (BCI) bought the cave mouth and a buffer of 697 acres as a wildlife sanctuary. In 2014, in the face of plans for a 3500-home development on 1500 adjoining acres, additional land around the cave was purchased through a partnership joining BCI, the Nature Conservancy, the Department of Defense, and the City of Austin. The purchase protected the bat colony, and also secured golden-cheeked warbler and black-capped vireo habitat, Edwards aquifer recharge lands, and continued military operations at Camp Bullis.