Biologist helps save bats in mines

He may not be caped, but in the bat world, Jason Corbett is definitely a crusader.

Since January, the Arizona conservation biologist has taken on a specialized role that has him descending into mine shafts to ensure bats living underground don’t become casualties of efforts to close abandoned mines across the Southwest.

“It’s easy enough to exclude bats from mines. There’s no reason for them to be entombed,” said Corbett, who works out of Tucson as a coordinator for the nonprofit group Bat Conservation International. “It’s easy enough to deal with.”

As someone designated to stick up for the little -- albeit furry -- guy, the bat buff travels around Arizona and other states offering inspections and recommendations for bat-safe mine closures. He is getting more companies and agencies to agree that doing nothing would be senseless.

Bats occupy an important niche as nocturnal predators. They help the ecosystem by eating insects, including pests that eat crops like cotton and corn.

Angie McIntire, bat management coordinator for the Arizona Game and Fish Department, said mines can house thousands of bats. They may use a mine only for a couple of months, but it could be during such crucial times as giving birth or feeding young.

McIntire and Corbett said there is no way to gauge how many bats may have been lost in mines. There is no official survey. But they’ve heard of such occurrences.

“I’m sure sites have been closed without any thoughts to bats or even knowledge they’re in there,” McIntire said.

Bat Conservation International first started a national bats-and-mines program about 12 years ago. More recently, officials decided to have a coordinator devoted specifically to the Southwest.

Corbett’s mine visits are generally determined by when government agencies and groups approach him with mine locations. But sometimes he will learn about a site and initiate contact. The real work begins once he and a support team, usually a trio of land officials and wildlife biologists, decide to go in.

While Corbett routinely inspects caves and horizontal shafts, vertical shafts are a bit trickier. He uses ropes and a harness to lower himself into the shafts -- some more than 500 feet deep. Before touching down in a shaft, Corbett will use a pole or tracking stick to probe for other critters. He once came down near a rattlesnake but was able to gently move it away.

Once he’s landed, Corbett looks for signs of bat life, such as bat droppings -- known as guano -- or meal leftovers in the form of insect parts. But the research doesn’t stop there.

“I’m looking at the bigger picture: How does that one mine fit into the larger landscape in terms of providing quality of habitat,” Corbett said.

Afterward, he’ll make a recommendation.

If the mine is habitable bat space, Corbett will recommend constructing a steel gate that is narrow enough to keep humans out but that lets bats flit freely.

“If a mine is unsafe, putting a bat gate on is twofold: It keeps people out and also protects bats,” Corbett said. “The two goals are not mutually exclusive.”

If the danger to people is too great, bats can be driven out before filling up a mine. The process, called exclusion, involves putting wire netting over an access point for several days. Bats can fly out through the netting but can’t squeeze back in.

If no bats are found, mine owners will probably be free to seal up a mine however they see fit.

Deserted mines have long been a public concern.

The issue took on more urgency in Arizona last year when a girl fell to her death in a mine shaft in the northwestern part of the state. The Arizona State Mine Inspector’s Office estimates that there are more than 9,500 abandoned mines statewide. There are hundreds of thousands more across neighboring states.

In July, as part of an agreement between the U.S. Department of Defense and Bat Conservation International to work on projects together, Corbett visited shafts around White Sands Missile Range, an Army-run test site in New Mexico.

Trish Griffin, a wildlife biologist at White Sands, is optimistic that the department will approve funding for Corbett and a crew to conduct inspections twice a year at other military facilities, including Ft. Bliss, in Texas, and Holloman Air Force Base, in New Mexico.

“Our New Mexico installations are gearing up for having an increase in missions and more soldiers on the ground,” Griffin said. “It’s better we survey these areas ahead of time so that we know where the safety issues lie, and this is what we need Jason’s help on.”

With about 100 abandoned mines on military land, Griffin said, the service is looking to both protect soldiers and preserve bat populations.

At California’s Death Valley National Park, Corbett has contributed to a slow but steady stream of mine surveys. Linda Manning, a park wildlife biologist, said the park has between 6,000 and 10,000 mines. Many are in areas open to the public.

Manning said the mines need to be systematically surveyed and assessed for bat usage and safety closures. But hiring a contractor or consultant gets expensive.

Corbett, who conducted several surveys there in February, does much of his work for free or at a discount.

Chris Ross, leader of an abandoned mines program for the Bureau of Land Management in Nevada, praised Corbett for his understanding of not just the science but the social and demographic issues. He said Corbett makes assessments that are economical but don’t compromise public safety.

“He’ll prioritize and spend big bucks on expensive bat gates on the ones that are important,” Ross said. “The rest of them, we can chase the little dears out and fill [the mines] up cheaply.”

Corbett hopes to continue building relationships in other states, such as Colorado and Utah. Most mining companies have been cooperative about finding a way to let bats roost in peace.

“I have had really, really good luck working with everyone,” Corbett said. “They’re happy to have some help on these issues. They want to do the right thing, but like everyone else, they are strapped on resources.”