A researcher at Mammoth Cave National Park is fearful that a fungal disease is set to kill large numbers of bats in the region.
White Nose Syndrome was first discovered at the park in south-central Kentucky last year, and has impacted at least six of the eight bat species found inside the cave. Rick Toomey, director of the Mammoth Cave International Center for Science and Learning, says researchers at the park are expecting a spike in White Nose cases.
“Unfortunately we’re expecting potentially our next big milestone this year, when we may start seeing fairly large population drops, or possibly finding bats dying of white nose at the park.”
Watch: WKU Public Radio photojournalist Abbey Oldham recently produced a video exploring the potential impact of White Nose Syndrome on the bat populations at Mammoth Cave, and what the park is doing to combat the fungus:
Toomey says an estimated 6.5 million bats in North America have died due to White Nose Syndrome, although he believes the actual number could be much higher. Great Smokey Mountains National Park in Tennessee has recently seen a surge in bat deaths due to White Nose Syndrome—deaths Toomey says haven’t shown up yet in official estimates.
White Nose Syndrome causes a fungus to grow on bats that the mammals carry year-round. The problems begin to occur during the winter when the bats hibernate.
“As their body temperature reduces during hibernation, the fungus becomes active. And that’s when it starts to damage tissue,” Mammoth Cave National Park Public Information Officer Vickie Carson says. “It causes discomfort for them, and it wakes them up out of hibernation. They go out to look for food and water, and they use up their energy reserves. And they basically starve and die of dehydration.”
As for finding cures for White Nose Syndrome, Toomey says scientists are studying why certain bat species have so far been resilient against contracting the fungus, while others have been hard hit. Some theories suggest certain species have bacteria in their bodies that help them ward off White Nose.
Toomey, however, is skeptical there will be any sudden breakthroughs that will cure the problem. He says researchers are also looking at chemicals that could be applied to bats to combat the disease, though that approach presents several difficulties.
“Both in trying to deal with hundreds of thousands of individual flying mammals that you would have to catch and treat, or how a treatment might affect other things that live in the caves.”
Toomey says park official believe they will “lose a significant percentage of our bats due to White Nose. We hope that there are some of the species that are not affected—some of the tree bats, some of the cave bats that seem to be less affected—we hope that those populations can take over some of the insect-eating duties” normally done by bat species that are being hard hit by White Nose.
As WKU Public Radio reported in May, bats play an important role in the ecosystem as a major consumer of night time pests.
A 2011 study published in the journal Science estimated the economic impact of bats for the agriculture industry between $3 billion and $50 billion dollars annually. As White Nose Syndrome slowly inches south and west, it may begin to threaten areas whose economies depend more heavily on agriculture.
According to the study, a colony of 150 big brown bats eat nearly 1.3 million insects a year -- insects that could potentially be damaging to crops.
One of the ways Mammoth Cave National Park is trying to prevent the spread of the fungus involves visitors who tour the cave. After completing a cave tour, visitors walk over a mat covered in chemicals that kills any fungus that may have gotten stuck to the bottom of the tourists’ shoes.
Toomey says the ultimate key to defeating White Nose could come down to an old-fashioned case of survivor of the fittest.
“The individual bats that are able to survive this will hopefully pass down that ability to their young, and rebuild populations.”
But that won’t happen anytime soon, Toomey admits.
“Bats are a very slow-reproducing organism. So that’s a very long-term prospect, as opposed to a short-term prospect.