The endangered Indiana bat saw a 9 percent population increase between 2005 and 2007, continuing a 12-year rise in bat numbers. However, a mysterious illness in the Northeast poses a threat to this success.
The number of Indiana bats rose from 469,000 to more than 513,000 between 2005 and 2007, according to population estimate surveys by the U.S. Fish & Wildlife Service.
“While that seems like a lot of bats, every winter they come together in massive numbers in a few caves and mines to hibernate, making them extremely vulnerable,” said Robert Currie, a bat biologist with the U.S. Fish & Wildlife Service in Asheville.
Human disturbance at hibernation sites was the lead factor in the bat’s decline and led to its listing as an endangered species.
“Now the bat’s habit of aggregating in large numbers at hibernation sites may make them more vulnerable to the rapid spread of this new disease,” said Currie.
The disease was first noted in New York, where biologists documented the death of thousands of bats, including several hundred Indiana bats, all apparently infected by a fungus which formed white tufts on the bats’ muzzles, giving it the name white nose syndrome. In addition to the white muzzle, dead bats appeared to have used up their winter fat stores and had congregated much closer to cave entrances than usual.
Researchers are trying to determine if the fungus itself is responsible for the deaths or if its presence is a symptom of another problem.
Indiana bats have been known to hibernate in Western North Carolina. More commonly, however, the bats migrate to WNC and make it their home during the warmer months. Thus far, white nose syndrome has only been documented in New York and Vermont. Until they have a better understanding of the nature of the disease and how it’s transmitted, biologists urge cavers to help prevent its potential spread.
To that end, the Service provides these recommendations:
• Do not touch any bats (living or dead), especially those with a white muzzle or nose.
• If you are in a cave and see bats with white muzzles or noses, exit the cave immediately, avoiding contact with other bats. Do not enter any other caves prior to decontaminating your clothing and gear.
• Contact your state fish and wildlife agency or your nearest U.S. Fish and Wildlife Service office to report observations.
• Report any dead bats found outdoors or any unusual numbers of bats outside during cold weather, especially near a cave or mine where bats hibernate.
• Decontaminate your clothing and all caving equipment using these procedures:
– Remove your caving gear when you get to the vehicle and put it in a closed plastic garbage bag to prevent contamination of the interior or trunk.
– Wash caving clothes using hot water, detergent and a normal bleach cycle.
– Dry the clothes thoroughly and dry them at hot temperatures.
– Scrape the dirt from boots and soak them in a 10 percent bleach solution (one part chlorine bleach, nine parts water). Soak porous boots longer than nonporous boots.
– Wash or soak cave packs and thoroughly clean helmets and lights with a 10 percent bleach solution or a similarly effective disinfectant.