Clinging to the ceiling of an abandoned mine tunnel in Birmingham's Ruffner Mountain Nature Preserve, a tricolored bat is in trouble.

It's February, and the small, tufted ball of fur and wings is just a few feet inside the entrance to Ruffner's Mine No. 3. It should be much farther inside the tunnel, better protected from the cold, and waiting for spring to reemerge and begin foraging on mosquitoes, moths and other insects in the urban nature preserve just south of Birmingham's East Lake neighborhood.

That probably won't happen. The bat is showing signs of infection with white-nose syndrome, a fungal disease that has caused more than 95 percent mortality for this species in Georgia.

Ruffner Mountain's bats are very likely to follow the same path, according to Chris Cornelison, a PhD researcher studying white-nose at Kennesaw State University in Georgia.

"White-nose syndrome is going to move through that population pretty severely," Cornelison said. "It would be my prediction that we'll continue to see declines until they probably hit about five percent of that historic population."

Cornelison conducted that survey with Jamie Nobles, Ruffner Mountain's Conservation Director, and Dottie Brown of Ecological Solutions Inc. He said they counted more than 600 bats in their limited exploration of the mine tunnel, and believe there were more than 1000 tricolored bats hibernating there last winter.

That makes it one of Alabama's largest tricolored bat hibernacula, according to surveys conducted by the Alabama Bat Working Group, a collaboration of state wildlife officials, researchers and volunteers. Or at least one of the largest ones left.

"Cathedral Caverns used to have many, many tricolored bats," said Nick Sharp, the Alabama Department of Conservation and Natural Resources' lead bat biologist. "There's no telling how many bats used to be in Cathedral Caverns.

"I suspect Cathedral Caverns once upon a time rivaled Ruffner Mountain No. 3, but those bats [in Cathedral] have all but disappeared."

Cathedral Caverns also tested positive for the fungus that causes white-nose, and all signs point to that disease as the driving force in the population declines.

Cornelison said the bats he encountered at Ruffner were in "at least" year two of a white-nose outbreak, possibly year three. The greatest mortality usually occurs in years three and four.

"I would not be surprised to hear that spring counts show a 50 percent or greater reduction in those bats," Cornelison said. "I hope that is not the case, but unfortunately that is the trend that has been observed in neighboring states with that species.

"It's not a very positive outlook, but you never know."

Species in peril

The tricolored bat got its name from its fur, which is dark at the base, lighter in the middle and bears a yellow-brown tip. It is known as a slow flyer, hovering over water bodies and around the edges of forests to hunt insects during the summer.

It's the smallest bat in Alabama, and until recently it was one of the most abundant. In fact, Sharp said, the bat was so common, that there wasn't much of a push for new research on the species here.

"The fact of the matter is, the species that are going extinct are the ones that get the money, that's the way things work," Sharp said. "We start studying them when they're in danger of going extinct."

The bats reproduce once a year, with females birthing one to two pups usually around late May or early June. Beyond that, Sharp said, there are still significant questions about the bat's life cycle, especially in Alabama.

"Another complicating factor in trying to conserve and manage and support these bats is we don't know how to do it," Sharp said. "We know very little about their summer habitat use and their general natural history and breeding biology.

"Folks have started looking at that now."

There is also very little survey data on tricolored bat populations in Alabama caves before white-nose arrived. Most of the surveys began in 2010. White-nose was first confirmed in Alabama in 2012.

Alabama caves that have tested positive for white-nose have all shown a 70-95 percent drop in observed tricolored bat populations within a few years of the arrival of the disease.

White-nose syndrome is caused by a fungus, Pseudogymnoascus destructans, which is not native to North America. The prevailing belief among wildlife agencies is that spores of the fungus were brought to American caves by hobbyists who did not properly wash their gear after visiting European caves.

Once the fungus crossed the Atlantic, bats and other animals have spread it from cave to cave, causing a slow-moving wave of the disease from that radiated out from New York throughout the Appalachians, across the Southeast and Midwest, with more isolated outbreaks confirmed in north Texas and Washington state.

The fungus causes white growths to appear on the bats, often around the nose and mouth, or sometimes on the wings. The fungal growth irritates the bats and prevents them from reaching deep hibernation in winter. The bats use too much energy at a time when they are meant to be dormant, and sometimes leave the safety of their caves to forage for insects.

Infected bats are sometimes spotted around cave entrances in the late winter, sometimes behaving erratically or otherwise showing signs of distress.

Just like the ones encountered in the February survey. Nobles said there are several old mining tunnels at Ruffner that recreate cave conditions for the bats, and the white-nose fungus has been found in all three portals that have been surveyed.

"With the tunnels being as close as they are, if you find it one, you're going to find it in all three," Nobles said. "And we did. We found more individuals in mine No. 3, and also more individuals with white nose."

Tricolored bats are one of the most vulnerable species to white-nose syndrome, being one of the smallest hibernating bats in North America. Since they're so small to start with, it's harder for them to build up enough energy to survive a fungus-agitated winter.

Cornelison said the tricolored bat was once Georgia's most abundant bat, before white-nose wiped out 95 percent of the population.

"[White-nose] showed up in Georgia in 2013 so that's four years and 95 percent loss," Cornelison said. "It's unprecedented in a wildlife disease.

"It's arguably the most severe wildlife disease that's ever been observed."

The tricolored bat has been proposed for protections under the Endangered Species Act, but that proposal is still under evaluation by the U.S. Fish and Wildlife Service. Cornelison said the species is expected to gain some level of protection from the federal government due to the severity of the declines.

Due to the lengthy review process, it's unclear when a decision might actually be made.

"There's some concern they could go extinct before we actually list them," Nobles said.

'If you like food, thank a bat'

As to why Alabamians should care that one of the state's most common bat species seems on the brink of irreversible decline, Sharp said he steers that conversation to the dinner table.

"What I tell people is 'if you like food, thank a bat,'" Sharp said. "All our bats in Alabama are insectivores and they eat billions of insects every night."

Sharp pointed to studies finding that in North America, bats provide agricultural pest control benefits worth billions of dollars every year, not to mention feeding on a lot of insects that are undesirable for other reasons. Another study showed bats provide more than a billion dollars' worth of benefits to corn crops alone.

"Everything we eat has corn in it in some form or another," Sharp said. "All our livestock are fed corn, so if you like to eat, you should thank a bat for that."

Opportunity lost?

Cornelison and Sharp said little can be done at this point to save Ruffner's bats.

Ruffner built steel gates over the entrances to Mine No. 3 and Mine No. 2 to prevent people from spreading the fungus to new areas. There is no treatment for white-nose syndrome that's been proven to work in the field.

But Ruffner's population could have served as a living laboratory to help researchers develop treatments for white nose that might be useful elsewhere.

This summer, Cornelison applied for a federal research grant to use Ruffner's bat population to test potential treatments for white nose, but he did not receive funding.

"I feel really good about the proposal we put in," Cornelison said. "I believe it scored highly, but it's just a very competitive process and that's the way these sort of research projects go."

Cornelison said the Ruffner site was an ideal location to test white-nose treatments, because it had a large bat population with an active outbreak, and it was an already disturbed site, not a natural cave system with a functioning ecosystem to worry about.

"This was the best-case scenario for Ruffner to be involved in promoting the conservation of bats," Nobles said. "In the meantime, we're still going to do surveys, but all we can really do is observe.

"Because white-nose is time-sensitive, you only have so long. That mine that had 600 bats this year might only have 200 next year and the year after that, it might have 20, at least with that species of bat."

The project would have tested two different techniques to reduce white-nose mortality over two winters. One group of bats would have received a "probiotic" bacterial treatment that has been shown in labs to slow the growth of the fungus. Another group would get an anti-fungal aerosol that is mild enough to avoid damaging bats and other cave-dwelling wildlife. A third group would receive both treatments.

But Cornelison would also have to have a control groups of bats receiving no treatment to prove that his treatments worked. The clearest proof of the effectiveness of the treatments would be for the subject group that received the treatments to survive at higher rates than the rest of the cave. Otherwise, he said, researchers would wonder whether other factors in the cave besides his treatments were responsible for any resistance to the disease.

In other words, the project wasn't about saving Ruffner's bats, but about developing techniques that might prevent future caves - or the species as a whole - from suffering the same fate.

"There's a bigger game afoot," Cornelison said. "Within the context of the species, the bats at Ruffner don't matter. To people there locally and it's their backyard, the bats are very important, but what we want to do is not just save bats in Georgia or Alabama, we want to develop tools that can be taken across the affected range.

"It would take these kind of controlled trials to demonstrate that these techniques are effective and scalable."

Cornelison said stopping white nose in Georgia was essentially a lost cause, and Alabama was following the same path.

"The fact of the matter is we're post-collapse in Georgia with this species," he said. "It's a greater than 95 percent decline across the state, so even if our treatment was effective in Georgia, it would take over a century -- if we stopped all white nose mortality -- to get back to our historical numbers.

"In those cases, the die is cast. What we're trying to do is utilize those resources to help states where white nose hasn't yet taken hold. That's what we were trying to do at Ruffner."