FORT SAM HOUSTON, Texas -- With about 28,000 acres of predominantly wild landscape, Camp Bullis is a hot spot for military field exercises and battlefield training.

While the range remains a go-to place for realistic training, it recently has gained attention, not of the military nature, but for its work with Mother Nature.

Camp Bullis is not just home to a slew of military training missions, but is also home to five federally endangered species, most notably the golden-cheeked warbler.

The tiny bird, which migrates up from Mexico to Central Texas each year, likes to nest in the old, thick growth of oak and juniper so common on Camp Bullis and the surrounding areas.

"Our most recent annual species surveys have estimated about 1,100 warblers at Camp Bullis, one of the bigger populations in the Texas Hill Country," said Chris Beck, Natural Resources manager, Directorate of Public Works.

Beck is one of several full-time environmental specialists dedicated to protecting and enhancing natural resources at Camp Bullis. They have the challenge of balancing critical military training missions with a delicate ecological system.

"We work closely with U.S. Fish and Wildlife Service and other environmental agencies to ensure we are doing what we need to do in our conservation efforts," said Beck. "We spend hundreds of thousands of dollars each year directly on conservation measures and research."

Included in the measures is the protection of endangered species like the warbler and the lesser-seen black capped vireo plus three cave invertebrates, or bugs. However, a growing population of endangered birds can be a show-stopper for training in the vicinity.

Part of compliance measures involves designating "core habitat" from warbler observations along with a seasonal (March 1 to Aug. 14) 100-meter light, noise and smoke buffer zone, "meaning increased protection in the areas during the nesting season," Beck said.

Additionally, the military is restricted to impacting less than 2 acres of trees a year in the areas of occupied habitat.

Of the approximately 28,000 acres at Camp Bullis, about 10,000 acres are identified as potential habitat. Construction at Camp Bullis is therefore concentrated in non-habitat areas to limit the impact on the environment.

Along with the airborne variety, resource managers are also looking to the ground for endangered species, to include the two species of cave beetles and one cave spider at Camp Bullis. These cave bugs seek out deep, dark crevices in underground caves, which also happen to serve as recharge features for the Edwards Aquifer. The aquifer, which is the largest sole-source aquifer in the country, provides water to about 1.7 million people.

"These caves are directly tied to aquifer recharge," Beck said. "To prevent possible contamination, we have vegetation buffers around these caves that are dedicated to keeping the buffer area as pristine as possible."

Because these caves occur in the recharge zones, resource managers keep a close eye on the endangered invertebrates that dwell there since their continued existence is just as important on a human level as on an ecological one.

"These invertebrates are an indicator species," said Beck. "We ensure they are thriving. If they're healthy, that means the aquifer is healthy."

As a result of their efforts, the endangered species at Camp Bullis are flourishing. However, a significant increase in the warbler population has been a source of concern -- and celebration --in recent years. "The warbler population has increased 50 percent over the past five years calculated on a running three-year average," Beck said.

Situated in one of the most coveted areas of the city, developers are swiftly closing in on the installation, cutting a wide swath into the forests around Camp Bullis and forcing the warblers to seek refuge on post.

"Endangered species don't stop at the fence line," Beck said. "According to longstanding federal law and U.S. Fish and Wildlife Service guidelines, everyone, not just the military, is prohibited from 'taking' endangered species.

"The military is a good steward of the environment, as we should all be," he said. "However, we cannot shoulder the burden of environmental compliance alone. We need the community to help."

Post leaders continue to work closely with environmental agencies and local and state government officials to protect Camp Bullis from encroachment, Beck said.

According to Jim Cannizzo, an Army environmental lawyer, Fort Sam Houston leaders have called for legislation that would require developers to give notice when construction that involves significant tree clearing, 2 acres and up, is within a 5-mile radius of Camp Bullis. Also, developers and realtors would be required to inform buyers that they are purchasing property adjacent to a busy military facility that may routinely cause noise and other issues.

Finally, the Army would like to see a state law passed that would require developers to conduct an endangered species survey before clearing significant amounts of trees around Camp Bullis, Cannizzo said.

Other efforts under way include a request for counties to require use of dark-sky lighting within 3 miles of Camp Bullis. The lower-intensity lighting is angled toward the ground, making the lighting friendly for next-door neighbors as well as military neighbors.

The goal is to protect Camp Bullis so it can continue serving as a military training ground for the Army, Air Force, Navy and a host of other federal agencies, Cannizzo said, which is a mission directly tied to the continued viability of Fort Sam Houston.

Under the Base Realignment and Closure initiative, the Fort Sam Houston community is slated to grow by more than 11,000 personnel by 2011. The growth is, in part, based on the proximity of Camp Bullis' field training grounds, Cannizzo said.

"The field training area (Camp Bullis), along with a large clinical facility (Brooke Army Medical Center) and medical training facility (Medical Education Training Campus), make Fort Sam Houston a logical choice for centralizing medical training here," Cannizzo said. "But if you knock off one of the legs off the three-legged stool, it collapses."

As post leaders work to protect Camp Bullis from encroachment, the resource managers will continue their efforts with an eye toward the sky, and to the ground.

"We'll continue our work toward ensuring the viability of species here," Beck said. "I think that speaks volumes for the military's dedication to natural resources and conservation."