for National Geographic News
This summer scientists hope to finally crack the case of the mysterious ailment afflicting bats in the U.S. Northeast—before time runs out for the animals and the local environment.
The emergence of pregnant females from their wintering grounds should provide vital clues to the extent and transmission mode of the affliction, known as white-nose syndrome.
First identified in February 2007 among hibernating bats in caves outside of Albany, New York, the ailment has became especially troubling this year, with signs of the illness spotted at more than two dozen caves and mines used by hibernating bats around New England and New York.
Mortality rates in affected hibernation sites can be as high as 80 to 100 percent, and tens of thousands of bats have been found dead.
Because a single bat may typically eat some 3,000 insects a night, experts say, the consequences could be dire for entire ecosystems. (Related: "Early Bats Flew First, Developed 'Sonar' Later [February 13, 2008].)
"What we saw last year was kind of just one cave affected, and this year we have seen many hibernation sites in multiple states," said wildlife disease specialist Kimberli Miller at the National Wildlife Health Center in Madison, Wisconsin.
"It's hard to predict whether next year it will be in even more locations or whether it won't," she added. "It is definitely a big concern."
Winter Sleep Cut Short
The mysterious ailment gets its name from the white fungus that grows on bats' noses and often on other body parts. It has been seen in little brown, big brown, northern long-eared, and eastern pipistrelle bats so far.
Scientists are unsure how, or if, the disease is spread from bat to bat. The fungus may be the primary pathogen causing the syndrome. Or it may be that normally present fungi have been able to grow unchecked in animals weakened by illness.
"They've used up all of their fat stores, they are emaciated, and instead of having enough fat to make it through the winter—they didn't," Miller said.
"We don't know at this point if they weren't in healthy condition going into hibernation or if something occurred during hibernation," she said, noting that some bats even emerged from their winter slumbers when food is scarce—a clear sign of trouble.
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