TINKER AIR FORCE BASE, Okla., -- They knew he was there, his camouflage blending in with the long grass.
The searchers moved slowly, peering intently at the ground and prodding occasionally at the grass while listening to the beeping of the radio transponder that told them their prey was close. But the searchers aren't soldiers hunting a sniper; they're scientists looking for lizards. The Texas Horned Lizard, to be exact.
"These guys are colored to blend right in with the soil and ground colors," says Ray Moody, staff biologist for Tinker.
Even armed with radios tuned to track transponders placed on the lizards, Andrew Reeves of the Oklahoma City Zoo admits the diminutive reptiles "can still be difficult to pinpoint."
The search for the lizards, commonly known as Horny Toads, is part of ongoing efforts by Tinker biologists and others to study and protect the reptiles found on base. Although not on the threatened or endangered list, the lizards are a "species of special concern" in Oklahoma as their population is declining.
"The Texas Horned Lizard is an iconic species for our state," said Mark Howery, staff biologist with the Oklahoma Department of Wildlife Conservation. Once found throughout the state, the lizard is now rare in Eastern Oklahoma and a even harder to find within the Oklahoma City metro area.
The colony of Texas Horned Lizards on Tinker is estimated at 50 to 60 and seems to be relatively steady. Normally living three to six years, the lizards rarely venture more than several hundred yards from their birthplace. They live on ants, consuming more than 200 per day, and rely on camouflage to remain hidden from predators, such as snakes and birds of prey. In an emergency, they can also squirt blood from their eyes or puff themselves up to appear too large and spindly to eat.
"But if a big copperhead comes along," Mr. Moody said, "they might be out of luck."
Humans, however, pose the largest threat. A combination of urban development, a change in the lizards' food source and the introduction of non-native grasses are cited by scientists as the source of the lizards' decline throughout Oklahoma. But, as Mr. Howery points out, scientific knowledge of the lizard isn't complete.
Mr. Moody says they discovered the lizard colony on base several years ago and began studying the population, using a combination of student volunteers, Geographic Information System and radio transponders to keep track of the lizard population. Since 2003, annual summer-long studies are conducted in cooperation with student scientists, the Oklahoma City Zoo and state wildlife officials.
"We're basically going out in the field, capturing lizards, taking them into the laboratory and tagging them," Mr. Moody said. "Every lizard we're finding, we're tracking."
The search for lizards runs from late spring to late autumn when the reptiles are active. They hibernate through the winter.
Although the radio transponders need to be replaced approximately every 10 weeks, those that are captured and are large enough have an electronic PIT tag inserted with information that can be scanned and read by scientists for up to 75 years. Researchers are also using GIS to track and digitally map the movements of individual reptiles.
"It's a very handy tool," said Jenifer McCanne of Parsons Inc., the company that supplies the GIS equipment. "It's essential for tracking these lizards."
"We've been able to use Air Force technology ... to learn more about the lizards," Mr. Moody added.
John Krupovage, natural resources manager for Tinker, says the study of the lizards is important because if they are ever placed on the endangered list, it could restrict developments on base that may ultimately affect support given by Tinker to the warfighter.
"We don't want land-use restrictions," he said.
Victor Bogosian, a graduate student working on the lizard project, said the research being done at Tinker is important because scientists don't yet know enough to develop a consistent management plan to preserve the species.
"We're not at that stage yet," he said.
"We're very excited by the work done at Tinker," agreed Mr. Howery. "It's helping us to get some better data on the Texas Horned Lizard."
That knowledge is being shared with researchers in Oklahoma and elsewhere.
Even while nearby base housing construction nears completion, conservation efforts are underway to restore areas of Tinker to natural prairie lands to accommodate the lizards and other wildlife in the area. Restoration work involves eliminating non-indigenous plants and replacing them with native vegetation.
"Planting native grass is a real challenge because it's a slow grower and we as a society want things instantly," Mr. Krupovage said. "It's something that takes a good deal of patience."
"We have worked very hard to implement conservation efforts," said Col. Allen Jamerson, 72nd Air Base Wing and Tinker installation commander, adding that "we're very proud of our efforts."
Mr. Krupovage said the goal is to strike a balance between the natural environment and human development. Altering any ecosystem, he said, can have long-term -- and often unforeseen -- consequences. Even if the lizards are hard to see, we might notice them if they're gone.
"If you pull something out of a system, it may disrupt the whole system," he said. "With the Texas Horned Lizard, we don't know what would happen if we take it out of the system."