Charlestown — The three researchers lay flat on their backs on picnic blankets, gazing up at the deepening dusk, and at the looming silhouette of the barn’s peak.
There, a crack in the woodwork of the aging structure was momentarily filled by a small furry body. An observer might have mistaken it for a large mouse, or a small rat, but no rodent could do what this animal did — it dangled from the edge of the crack by its feet, and then let go, launching itself into the void.
In the same instant, the bat — among the survivors of a horrific disease that has killed more than 90 percent of its fellows, and possibly more in the Upper Valley — fluttered manically into the night with an almost-inaudible whicker of leathered wings.
Katherine Ineson, a doctoral student at the University of New Hampshire who was leading the field research team last Tuesday, clicked a button on a small counter she held in her right hand.
One.
The other two researchers — UNH undergraduate Joe Poggi, of Derry, N.H., and Carson Halabi, a high school student from Connecticut — did the same with counters in their hands.
But there was no time to compare notes. Another bat was already emerging from the aperture in the barn, skirting down the length of the eave before turning the corner and flying into the night. Then another.
Ineson is one of a burgeoning population of professional and volunteer bat researchers who have been anxiously studying the impact of white nose syndrome, the bat-killing disease associated with a European fungus that began sweeping through American bat populations around 2006.
The fungus grows on the walls of the caves and mines in which bats hibernate.
When bats are hibernating, they become a good source of nutrients or energy for the spreading fungus, Ineson said.
The fungus covers the muzzles of bats in a fuzzy white growth that gives the syndrome its name. It also grows on their wings, ears, and tails — anywhere the bat has exposed membranes — and it often kills skin tissue.
Some of the bats die without waking. Others, sensing the danger, wake up early, but there’s little they can do to save themselves. They need to feed to sustain their newly awakened metabolism, but it’s winter — their prey, typically small flying bugs and insects, are absent.
Researchers sometimes find their corpses, defeated, in the snow.
Ineson doesn’t study these winter hibernation sites herself.
“I’m focusing on summer, when they’re reproducing and having pups, which is important for the population,” she said. “They need new individuals to survive.”
But she has seen affected bat individuals, scarred survivors that have somehow threaded the needle between killer cold and killer fungus and flown on tattered wings to a fungus-free summer roosting site, like the old Charlestown barn where Ineson waited last week.
The three spent nearly an hour on their backs, carefully focused on the emergence of the bats, which were in turn focused on the thick population of mosquitoes that, themselves, were swarming the researchers to form a three-way cycle of survival.
Ineson and her data will be one small detail in one of two possible stories concerning the future of bats. It could be their last days on the continent — or their biggest comeback in recorded history.
The Fungal Menace
When white nose syndrome, which was first documented in New York, began decimating bat populations a decade ago, there were many bats, and few people to study them.
Ineson estimates that the Charlestown barn along North Hemlock Road used to hold about 1,000 little brown bats, which is the most common of nine bat species found in the Twin State region.
Alyssa Bennett, the leading bat expert on the payroll at the Vermont Fish and Wildlife Department, says bat researchers on the job before white nose syndrome used to see massive colonies.
Vermont’s largest, in Dorset’s Aeolus Cave, once numbered about 700,000 bats.
But, between 2008 and 2009, the fungus killed millions of bats throughout the Northeast, researchers estimate. The Dorset colony lost about 90 percent of its individuals.
“It was a carpet of dead bats on the floor in Dorset,” Bennett said, relating stories she’s heard from saddened and shaken predecessors at the department. “It was a bloody, nasty mess and all sorts of scavengers coming in. It sounded like the smell was horrible. They thought there were 100,000 dead bats on the floor at the entrance to that cave.”
And closer to home, researchers counted nearly 1,000 bats at Strafford’s Elizabeth Mine in 2006, mostly little brown bats.
When researchers returned in 2009, they found just a single lonely bat. In 2011, they scanned the cave with infrared goggles and found just two individuals. Since then, as far as they can tell, the cave has been devoid of bats.
The Public Awakens
If there’s a silver lining in the massive dieoffs, it’s that the bat has received a total makeover in the public eye. Fifteen years ago, say Bennett and Ineson, people only associated bats with disease, vampires and other horror movie tropes.
Now, the bat population crisis has sparked a deep vein of sympathy, and a recognition of the critical role bats play in the ecosystem, not least by clearing away enough mosquitoes to make summer evenings more enjoyable for humans.
“Anecdotally, what we hear from the public very often is, ‘I used to sit on my back deck when there were bats without being eaten by mosquitoes and now I can’t,’ ” said Bennett.
“The general perception of bats is improving,” said Ineson. “There’s been more education, lots more press on the effects of white nose syndrome, lots more awareness of bats and how their populations have been affected.”
And that public goodwill has been made tangible in the mobilization of resources to help study bats and their current plight.
State departments, agricultural cooperatives, universities, and nonprofits like New Hampshire Audubon and the Vermont Bat Center are just some of the groups that have supported a network of bat-preservation efforts that include providing bat housing, surveying populations, and funding laboratory studies on bat DNA to try to tease out the difference between bats that outlive the fungus, and those that die.
A New Hope
Last week was the third time this summer Ineson and Poggi traveled to the Charlestown barn. In May, they counted 206 bats, and in June, 212. Now, the females have had a chance to rear their pups to adulthood — one per mother — so for the first time they expect to count the juveniles as well.
When the last bat has thrown itself out of the hole in the barn, Ineson waits an additional five minutes to make sure there are no stragglers, and then consults her counter.
Three hundred and twenty bats, she says. Poggi and Halabi counted fewer, but Ineson, as the most experienced researcher, sticks with her number.
And while it isn’t definitive, the number is a good one, Ineson says. It supports a larger narrative that bat expert are starting to tentatively float in academic journals and the public — that bats might, just possibly, have found a way to coexist with the disease.
In January, some of Ineson’s UNH colleagues, including researchers Jeffrey Foster and Katy Parise analyzed data for infection and population trends in little brown bats. They found that colonies that had weathered the initial storm of white nose syndrome were seeing much lower infection levels than colonies that had only recently been exposed.
In other words, it looked like individual bats that survived one die-off were less likely to die in subsequent years, resulting in a leveling off of mortality.
And this is just one of many promising signs.
“The colonies I’m studying, I have seen the summer colonies increasing over the last several years, at least at some sites,” Ineson says.
The Charlestown emergence count complete, the researchers enter the barn and set up a temporary lab on an old table. The electronics, scales, injection needles and banding equipment they pull from tackle boxes and plastic totes combine to form a mishmash of tools that seems part fishing expedition, part Ghostbusters.
They next strap on headlamps and clamber up into the attic. It’s pitch black, and hot, with guano-laden plastic tarps spread out over the wooden flooring.
Ineson, sharp-eyed, points out a tiny bat peeping out from a space between the wooden planks that join the ceiling to a support beam. As she and Halabi approach with a headlamp, it crawls deeper into the crack. They leave it alone. Soon there will be plenty of bats to see up close.
They erect a bat trap, called the “Harp” because its defining feature is a series of taut plastic filaments that hang vertically over a plastic tub.
Most of the bats are out feeding, but some come back to the roost to take a rest, or to feed their young. In the dark, enclosed space, Ineson says she sometimes feels the wind on her cheeks as they flutter past her face.
Within minutes, two bats have flown into the strings, and fallen into the plastic tub.
Poggi and Ineson pluck them out of the tub, holding them firmly in gloved hands as they carry them back down to the temporary lab. The average bat, says Ineson, weighs no more than two nickels.
Poggi’s holding a big brown bat, a distinct species from the little brown bat that sometimes shares roosting space. It chitters angrily, a never-ending stream of chirps that sound like a cricket on steroids.
“It’s a little bit of a distress call,” said Ineson. “Generally, the big bats don’t have as much damage.”
Poggi stretches out its wing and uses a ruler to measure it.
“Female,” he says. “She’s lactating. Need anything else?”
“How can you tell if a mother is lactating?” asks Halabi.
Poggi uses one thumb to brush back the fur around the bat’s nipples.
“You can usually see the ring here, and it’s a little bigger,” he says.
Moments later, Poggi steps outside of the barn and into the surrounding darkness to release the bat into the night. For the creature, the entire ordeal has taken no more than 20 minutes.
The second bat is a little brown, a male, which Ineson is soon stretching out on the light table to inspect for signs of wing damage.
“This one is a pretty young juvenile,” Ineson says. She points to small gaps between the bones that run like dark rivers beneath the surface of its wing. “You can see the gaps that we were talking about. It looks like a younger juvenile, just based on the size of the gap. And you can see a few little mites on there.”
Ineson slips a light metal clip onto its right wing. It fails to take flight into the sky, so she carries it back up into the barn’s attic.
“Sometimes the juveniles get a little dazed,” she says.
They head back up to the plastic tubs to collect more bats. By the time they pack up their lab at 3 a.m., they will have captured 50 bats, and banded 47 of them.
“Researchers in the area have banded these colonies in the past. I am catching some of the bats that they originally banded,” Ineson said. “We’re definitely seeing bats that have survived their first year and are reproducing. We’re seeing lots of bats that do have wing damage early in the summer and heal over the summer. All of that is hopeful.”
Bennett is wary of the idea that, after a decade of horrific mortality counts, bats are on the comeback.
News reports trumpeting bat successes are misleading, she said.
“It’s a really different story depending on the species,” she said.
In both Vermont and New Hampshire, four species — including the little brown bat — are among the only mammals that make the endangered species list.
Of those, northern long-eared bats are among the hardest hit, having seen 95 percent mortality and which seem to be experiencing continued decline.
Little brown bats were decimated, but she says they now seem to be holding steady.
And big brown bats have been less affected than the other species, and in some cases seem to be creeping into habitat once dominated by little browns.
More so than almost any other species, she said, their future depends on the public. “They prefer to live in people’s houses in the summer,” she said. “They’re really highly concentrated in barns and attics. If one person of two dozen decided to kill all those bats — we’ve heard cases in which someone decided to seal them in or spray them with wasp spray — that would actually be a significant portion of the population at this time.”
Bennett and Ineson both urged members of the public to help document the region’s bat colonies by reporting significant bat populations to state wildlife officials. Bennett said that, as of right now, she is aware of about two dozen little brown bat summer colonies in the state.
The Vermont Fish and Wildlife Department at www.vtfishandwildlife.com and the New Hampshire Fish and Game Department at www.wildlife.state.nh.us both maintain online bat colony reporting pages that can be accessed by searching “bat colony” on their websites.
Matt Hongoltz-Hetling can be reached at mhonghet@vnews.com or 603-727-3211.