[Note: This is the first post in a blog series on The Nature Conservancy’s new artificial bat cave, an experiment to help stop the spread of white-nose syndrome, a fungal disease killing millions of bats. Read the second blog here and also see an article in The New York Times about the cave.]
Six million dead bats.
When it comes to white-nose syndrome—the fungal disease responsible for those dead bats—good news is hard to come by.
The disease is spreading, fast. No one knows how to stop it.
“A lot of the stories you hear about white nose are very negative,” says Cory Holliday, director of the cave and karst program for The Nature Conservancy in Tennessee. “It’s a disaster. It’s a wildlife tragedy. And now we are embarking on an experiment that offers a bit of hope.”
I’m at that experiment today: a new artificial bat cave near Clarksville, Tennessee. Here, researchers hope a carefully engineered environment can provide a safe haven for bats—and possibly show the way out of one of the country’s most alarming wildlife crises.
A Bunker for Bats
Yesterday, I toured a small bit of Mammoth Cave National Park, the longest-known cave in the world, with expansive passages and seemingly endless side channels. But perhaps overshadowing the natural wonder was the worry about white-nose syndrome.
At the visitor center, an announcement played every few minutes asking — no, pleading — guests that had toured other caves to visit a special white-nose center. There, people doused their shoes in Lysol while park staff explained why this was necessary.
As the ranger detailed the horrors of white-nose syndrome, one visitor asked: “So, doing this will keep it out of Mammoth?”
“No,” he said. “We aren’t stopping it. It’s coming. We just hope we can slow it down.”
Compared to Mammoth, the artificial bat cave doesn’t look like much. It’s basically an underground concrete bunker, which, as Holliday puts it is “about the size of a single-wide trailer, with high ceilings” or 80 feet long, 11 feet wide, and 16 feet high.
It looks, frankly, more like an unfinished basement than a wildlife sanctuary.
Can it really help?
White-Nose: A Brief Primer
What do scientists know about white-nose syndrome? Distressingly, not much.
Here is what is known: In 2006, cavers reported dead bats in a New York cave. The disease was confirmed in 2007. From there, it has spread rapidly throughout the eastern United States, with reports now as far west as Oklahoma.
In 2010, it came to Tennessee, home to more than 9600 caves and 16 species of bats.
The disease is believed to have originated in Europe, and may be spread in part by humans, although neither has been confirmed.
White-nose syndrome is caused by a cold-loving fungus that thrives in caves. However, caves are a nutrient poor environment; there’s not much to eat. And so the fungus must survive on slim pickings: debris that blows into the cave, or bat and cricket guano.
But then each winter a veritable smorgasbord arrives in the form of thousands of hibernating bats. Bats may fly rapidly in the summer, but in winter they lower their body temperatures to hibernate in caves. Their immune systems are naturally suppressed as they survive on meager fat reserves.
The fungus attacks the bat, causing it to burn precious fats, which ultimately leads to death.
Three years after the fungus is found in a cave, hibernating bats have usually disappeared: All dead.
“It’s depressing,” says Holliday. “I’ve been in caves that have had lots of bats three years ago that now have none. It keeps me up at night.”
Hope in the Bat Cave
If there is any good news in the white-nose syndrome, it’s this: The fungus is easy to kill. Hot water, general household disinfectants or ammonia all do a good job of stopping it.
However, even that must be tempered with reality. Any of these treatments in a natural cave may very well kill the fungus, but it will also kill off cave microbes and invertebrates, many found nowhere else on earth. “It would lead to a collapse of the entire ecosystem,” says Holliday.
But not if the bats are hibernating in a special climate-controlled environment, where each spring any fungus can be easily killed.
Enter the artificial bat cave, one of the first experiments in stopping the disease’s spread.
And it is an experiment, one that rests on a lot of assumptions about white-nose syndrome rather than fact.
“A lot of the research on white-nose syndrome has focused exclusively on understanding the disease,” says Holliday. “The Nature Conservancy is not tracking the disease for academic reasons. We’re trying to put our experience to use. And we need to do something.
“There are risks with this project. There is so much we don’t understand,” he continues. “There are so many questions. It seems to go against sound science to proceed before you have answers. But if we wait until we have all the answers, there will not be any bats left.”
The artificial bat cave features an array of engineering marvels based on bat behavior and needs. An experiment, yes, but one based on the knowledge scientists do have.
In the coming days, I’ll be blogging on the science behind the artificial bat cave, why scientists believe it can work and even how you can do your own part to help the bats. I hope you’ll join my in-depth journey to the bat cave, the front line in the fight to save these special creatures.
Photo: Cory Holliday, cave and karst program director for The Nature Conservancy in Tennessee, surveys the outside of the artificial bat cave. Credit: Matt Miller/TNC.