Former U.S. Congressman Morris Udall once said, “The more we exploit nature, the more our options are reduced, until we have only one: to fight for survival.” While man’s place in nature is hotly contested, we can agree on one species that is, as we speak, fighting for survival: the golden-cheeked warbler. In our ongoing effort to protect this Central Texas songbird, we established Cibolo Bluffs Preserve, 1,244 acres of pristine warbler habitat.
Situated about 20 miles northeast of San Antonio, Cibolo Bluffs is a scenic landscape that encompasses nearly three miles of Cibolo Creek, which spans both Comal and Bexar counties. Much of the preserve features mature oak and Ashe juniper woodland, which is prime habitat for the federally protected golden-cheeked warbler, which only nests in the mature oak and juniper forests of Central Texas. The species has seen its numbers decline significantly in recent years due to rapid development across the region.
In addition to protecting valuable warbler habitat, Cibolo Bluffs also safeguards land over the Edwards Aquifer, which provides drinking water for more than two million Central Texans and serves as San Antonio’s sole source of drinking water, and buffers the adjacent Bracken Bat Cave, which is home to more than 20 million Mexican-free tailed bats, making it the largest bat colony in the world.
The preserve’s geology is mostly Edwards limestone, with underlying upper Glen Rose limestone exposed on bluffs along the creek at the western tip of the property. Due to the intersection of several area faults, rain that percolates through the shallow soil and underlying limestone creates interesting sinkholes, caves and other karst features, which species such as coyotes, fox and rattlesnakes utilize as dens.
Cibolo Bluffs was created in partnership with Bexar County and the United States Army; due to rapid development of the land surrounding Camp Bullis, the 28,000-acre military installation was fast becoming a ‘lone island of refuge’ for the warbler. Given the songbird’s status as federally endangered, the Army was no longer able to clear the surrounding juniper and oak woodlands in order to expand their medical training and combat facilities. In 2009, the Conservancy entered into a cooperative agreement with the Army to protect warbler habitat off-site in exchange for mitigation credits, which allow the Army to clear vegetation and develop the surrounding property.
Under measures required by the U.S. Fish and Wildlife Service, the Conservancy will maintain the property in its natural condition by protecting and restoring wildlife habitat and protecting water quality through watershed management. Additionally, our work will include monitoring sensitive species and removing invasive and exotic vegetation. Cibolo Bluffs was established as a preserve in 2011.