Less than a week after announcing that white-nose syndrome has infiltrated Alabama, U.S. wildlife officials revealed more bad news Tuesday: The mysterious fungal disease has begun to attack bats in two more national parks.
In a pair of press releases issued Tuesday, the U.S. Fish and Wildlife Service confirmed that WNS-infected bats have been found at both Acadia National Park in Maine and at Great Smoky Mountains National Park in North Carolina and Tennessee. The disease had already been documented in all three states - unlike Alabama, where the invasion is apparently new - but this is the first evidence that it's infecting bat colonies in these high-profile national parks.
Both of the newly discovered WNS invasions are troubling, scientists say. The Great Smoky Mountains provide a critical refuge for 11 different bat species, including at least six that hibernate in park caves and mines, making them susceptible to WNS. (The park is also home to Tennessee's largest hibernating population of endangered Indiana bats.) And as Acadia wildlife biologist Bruce Connery says in a statement, the arrival of WNS in that park suggests the disease is now well-entrenched in Maine, where it had previously been confirmed only farther west and inland.
"Coastal environments were not thought to have bats in winter and seemed insulated from areas where white-nose syndrome had been found," Connery says. "This year we have been getting reports about bats being active throughout the winter. We tested two bats found in the park this winter and discovered that they had the disease." White-nose syndrome first appeared in a New York batcave in 2006, and has since spread to 16 other states and four Canadian provinces. It remains poorly understood, but scientists caught a break last fall when they finally discovered what causes the disease: a previously unknown fungus called Geomyces destructans. Infected bats develop a white fuzz on their noses, wings and other body parts, and tend to display unusual behavior - namely waking up from hibernation too early, flying outside and trying to hunt insects that aren't there. The FWS estimates that G. destructans has killed roughly 6 million bats across North America in the past six years.
According to Acadia park superintendent Sheridan Steele, recent reports of bats flying at odd times will likely increase due to WNS. "We are more likely to see bats out during the daytime and during seasons when they are not normally active in Maine," Steele says in a statement, adding that he fears a domino effect. "Learning that white-nose syndrome has been documented in Acadia and Hancock County bats is disappointing. ... Losing even a small percentage of Maine's bats could have a devastating effect on one of nature's ecological controls of forest and wetland insects."
G. destructans may be new to Acadia, but the fungus had already been detected in the Great Smoky Mountains, the FWS notes. This is simply the first evidence of it directly infecting local bats, and comes despite concerted efforts to thwart its spread. In 2009, all 16 caves and two mining complexes in the park were closed to the public, part of a national campaign to stop people from spreading the disease. "While the confirmation of WNS in the park is not a surprise, it is still a sad day for the resource," park superintendent Dale Ditmanson says in a statement. "By continuing to monitor bat populations in our caves and forests we hope to minimize WNS affecting other bat habitats outside of our boundaries."
WNS is transmitted primarily from bat to bat, although researchers believe it may also be inadvertently carried between batcaves by humans, since the fungal spores can stick to clothing or shoes. As Connery points out, "the fungus cannot be killed simply by washing clothing and equipment. Managers and scientists are advising that unless people have special training and equipment, they should avoid bat-roosting areas to help slow the transmission of the fungus." The FWS keeps an updated list of cave closures on its WNS website, and also offers a guide on what you can do to help. The map below illustrates where WNS has been confirmed and reported so far: