On a balmy October evening, deep in the woods of Craig County, Wil Orndorff stood waiting at the mouth of a cave.
“We’re hoping the warm weather will bring them out tonight,” he said.
“Them” being the bats.
About 30 feet inside, a team of researchers had strung a net to capture the bats as they flew out at dusk to forage for food. The goal: to determine how many have white-nose syndrome, a disease threatening entire bat populations along the East Coast.
More than a million bats have died so far in the Northeast, where the disease was discovered by an upstate New York caver in 2006, according to the U.S. Fish and Wildlife Service.
To get a better idea of what’s happening in Virginia, scientists are monitoring bats in the caves where they hibernate — and where the disease can awaken them prematurely and then starve them to death.
On this night, the bats were not cooperating.
It must be too windy for them to come out, Rick Reynolds, a biologist with the Virginia Department of Game and Inland Fisheries, mused after more than an hour passed without a single netting.
So Reynolds and Orndorff, a karst protection coordinator with the state’s Department of Conservation and Recreation, squeezed through a narrow opening and followed the cavern’s winding route to where it abruptly dropped into a black hole.
“We were hoping they would be cooperative and we wouldn’t have to do this,” Reynolds said as he slipped into a cave-climbing harness. “But we have to go in after them.”
He and Orndorff then rappelled about 25 feet down the cliff, the glow from their head lamps quickly giving way to pitch darkness. About a half-hour later, Reynolds pulled himself back up, one hand gripping a black plastic garbage bag from which angry squeaks could be heard.
Back at the cave’s entrance, two other team members had set up a processing station on a folding table.
“We have work,” Reynolds told them.
Inside the bag were about 50 little brown bats, a species that resembles a winged mouse. Smaller paper bags held several bats apiece, each tightly shut with a clothespin. Lying on the cave’s rock floor, the bags vibrated from the beating wings inside.
“Hi, little brown,” Karen Francl, a biology professor at Radford University, said as she pulled one out and cupped it gently in both hands. The bat bared its tiny teeth and bit Francl’s gloved finger.
Unharmed, Francl measured the bat’s forearm, inspected its wings and weighed it on a set of digital scales. A bat’s weight this time of year, when it should be fattening up for hibernation, is a crucial clue in the search for symptoms.
White-nose syndrome — named for the white markings it leaves on an infected bat’s snout, ears and wings — is a fungus that irritates the victims’ skin to the point of rousing them from hibernation.
Awake when they shouldn’t be, the bats burn off crucial body fat as they flap around the cave. Sometimes they fly outdoors during the day, either freezing to death or starving during their futile search for mosquitoes and moths in the dead of winter.
“It was just heartbreaking to see those little critters coming out in the snow in broad daylight,” said Don Anderson, a caving enthusiast who assisted in a count in Bland County earlier this year.
A normal bat should weigh about 9 or 10 grams. Many of the ones examined by Reynolds’ team last month were underweight.
“You can do better than that, little guy,” Francl said after one bat tipped the scales at 6.6 grams. After inspecting the bat’s wings for sores and tears caused by the fungus, Francl placed a tracking band on its forearm and then watched affectionately as it fluttered away.
To be sure, not everyone has a soft spot in their heart for bats, or a deep concern about weight loss by a flying mammal often associated with Halloween and creepiness in general.
But a steep decline in the bat population — or even worse, the extinction of entire species — would mean more mosquitoes and other flying pests. One little brown bat can eat up to 1,000 mosquito-sized insects in an hour; a pregnant bat typically eats the equivalent of her body weight in bugs each night, according to Bat Conservation International.
It’s too soon to say just how bad the outbreak is in Virginia, Reynolds said. But clearly, the disease is spreading rapidly.
Since the state’s first case of white-nose syndrome was confirmed inside Breathing Cave in Bath County last year, the disease has been spotted in 19 more caves, extending all the way south to Smyth County.
The U.S. Forest Service has closed all caves and abandoned mines on its land to prevent cavers and others from spreading the disease. Evidence suggests the fungus is mostly transmitted bat to bat, Reynolds said.
Many underground expeditions on private land have resumed, said Anderson, president of the New River Valley Grotto caving club. Most cavers take care to clean and disinfect their boots and clothing, so as not to carry the fungus with them to an unaffected cave, Anderson said. Scientists believe the disease poses no threat to humans.
Of the 200 to 300 bats Reynolds observed on the walls of Shires Cave in Craig County the night of Oct. 26, only one had the telltale white fungus on its nose. But that sign usually doesn’t appear until the bats are well into their hibernacula.
By February, when researchers will venture back into the caves, they should have a better idea of how many bats are dying. Anecdotal reports are grim, with bat colonies in some Virginia caves down from thousands to hundreds.
No clear cause or cure for the disease has been identified. The U.S Fish and Wildlife Service in October announced a coalition of more than 50 agencies and organizations to address an epidemic that has spread to 11 states.
Some are calling white-nose syndrome the most serious threat to American wildlife in the past century.
After the last bat pulled from Shires Cave was examined and released, and the information stored in a database, Reynolds was worried. Far too many of the creatures are approaching cold weather with weights they would normally have in the spring, following hibernation.
“It doesn’t look very promising,” Reynolds said. “It’s not likely a good sign of them making it through the winter.”