A virulent bat disease has spread to Mammoth Cave National Park in Kentucky, putting its estimated 25,000 of the hibernating mammals in grave danger.

Park officials announced today that a northern long-eared bat living in the park's Long Cave contracted white-nose syndrome.

Named for the fuzzy fungus that grows on bats' ears, nose and mouth, the disease has killed more than 5.5 million bats in the United States and Canada since 2006.

"It grieves me to make this announcement," Superintendent Sarah Craighead said in a statement.

The arrival of white-nose syndrome in Long Cave, the park's largest hibernaculum, could be devastating for the park's nine species of hibernating bats, including endangered Indiana bats and gray bats.

White-nose has been known to wipe out more than 90 percent of cave populations if present for a year or longer, according the Fish and Wildlife Service.

The disease, which is not suspected to affect people, pets or livestock, is transmitted from bat to bat, but fungal spores can also be transported on cavers' clothing or gear.

The fungus has been confirmed in 21 states and four Canadian provinces since it first hit New York (Land Letter, March 1, 2012). This is the ninth national park affected.

Anticipating the potential that white-nose could spread to Mammoth, park officials developed a response plan several years ago, implemented decontamination protocols for cave visitors and began collecting base-line data about the park's bats.

"The data provide important information on which bat species are present and how many, when they give birth, and when they feed," Craighead said. "We now have five years of data collected prior to the arrival of white-nose syndrome, and will continue monitoring through the course of the disease."

There are more than 400 caves in the park. Long Cave has been closed to visitors for more than 80 years. Mammoth Cave, which is 390 miles long, will remain open to visitors.

"About 400,000 people tour Mammoth Cave each year, providing an excellent opportunity for us to educate the public about the importance of bats and the disease," Craighead said. "We screen all visitors before they go on a cave tour, and visitors walk across decontamination mats as they exit their tours."