To many people, bats are creepy little things that flit about on leathery wings, go bump in the night, and generally scare the bejesus out of us. If we set aside the Hollywood vision of crazed bloodsuckers, however, we find that these tiny fruit and insect-eating mammals are vital members of the community. They are pollinators and seed dispersers, who play an important role in the control of disease-bearing pests such as mosquitoes.
At the moment, however, bats are facing a challenge far more serious than their maligned reputation. Bat colonies in the eastern United States have been dying due to a mysterious ailment called white nose syndrome
, named for the ring of white fungus that appears on the faces of affected bats. These bats lose their body fat, weaken and eventually die of starvation during their winter hibernation period. The disorder has been known to kill up to 100 percent of the individuals in an infected cave.
Scientists are unsure whether the deaths are due to the fungus itself, or whether this is an opportunistic infection plaguing bats already weakened by some other cause. Regardless of its source, the disorder is spreading rapidly throughout the eastern United States and humans may be helping to pass it along. Researchers believe that visitors who enter caves and mines may be inadvertently spreading the disease on contaminated clothes, shoes, and gear, leading the U.S. Fish and Wildlife Service
to call for a voluntary moratorium on such activity.
Southern and eastern Illinois are home to several major hibernacula — cave or mine systems where bats gather to hibernate throughout the winter months. While our caves do not yet seem to be affected, the disease is headed our way and officials are asking for your help in stopping its progression.
Responsible spelunkers generally avoid all caves during the bats' hibernation period, which stretches roughly from October to March, as even small disturbances to hibernating animals can be detrimental to their health. Scientists believe that this practice is even more crucial now, and also ask that summer spelunkers avoid all caves in affected states as well as those adjacent. The current list of affected states includes New Hampshire, Vermont, New York, Connecticut, New Jersey, Pennsylvania, West Virginia and Virginia, however, cave closures have been recommended in nearly every state east of the Mississippi River and as far west as Oklahoma. While the federal government does not have the authority to close caves on private land, spelunkers are urged to avoid these sites as well, even if no warning is posted.
If you see a bat with white nose syndrome, a dead or dying bat, or a bat exhibiting strange behavior (such as flying during cold weather), please contact your state's wildlife service
and report the sighting. If possible, photograph the animal. As always, however, you should exercise caution when approaching a sick animal; bats may also be carriers of other diseases, such as rabies, which can infect humans.
Please check the National Speleological Society's website for recent cave closures
on white nose syndrome. The U.S Fish and Wildlife Service offers a helpful fact sheet
and regular white nose updates
, including announcements of recent research results.
While the cause of white nose syndrome remains elusive, steps such as cave closure may help to stop or stall its spread. Caves are wondrous places, full of beauty and surprise, and, with a little effort, America's bats will continue to call them home for generations to come.
A bat suffering from white nose syndrome (top), Marvin Moriarty
Biologists prepare to enter a mine in search of clues about the disease's cause (bottom), USFWS/Flickr