Signs of devastating bat disease found in two Minnesota caves
By John Myers
Forum News Service
A fungus that spreads a disease that’s nearly always fatal to bats has been found in two of Minnesota’s largest bat caves — the Soudan Underground Mine near Lake Vermilion in the northeast and a cave at Forestville/Mystery Cave State Park in the southeast.
The two Minnesota sites are considered among the state’s largest bat hibernacula — or wintering sites — and thousands of bats live in both.
The Minnesota Department of Natural Resources has scheduled a media briefing this afternoon to announce that the fungus has been found.
The fungus had never before been found in Minnesota but has been called the “worst wildlife health crisis in memory” by the U.S. Fish and Wildlife Service.
So far, the DNR reports, they have found no dead bats that have died from so-called white nose syndrome. Vermont's Aeolus Cave housed an estimated 400,000 little brown myotis bats before the disease struck. Two years later, researchers found only 36 bats alive,
“This is one of the most devastating diseases affecting wildlife in eastern North America,” Wendi Weber of the U.S. Fish and Wildlife Service said in a June statement. “Best estimates indicate that it has killed more than 5.7 million bats.”
White nose syndrome was first observed in 2006 in a cave in Upstate New York. Since then, it has spread rapidly west to 22 states in the United States and five Canadian provinces. The disease has reduced bat populations as much as 71 percent in states where it has struck and in some cases has killed nearly 100 percent of the bats in caves where the fungus has appeared.
It’s not clear how the disease spread so fast, but it’s believed that humans carry the fungus from one cave to another, and that bats may spread the disease themselves.
The Soudan mine is home to the largest known wintering concentration, or hibernaculum, of bats in Minnesota. An estimated 10,000 to 15,000 bats hang along 52 miles of horizontal tunnels and vertical shafts, most of them little brown myotis.
White nose syndrome is not known to pose a threat to humans, pets, livestock or other wildlife.
Report dead, diseased bats
Report bats flying during the day, clinging to trees or building exteriors in winter when snow is still on the ground, or showing white fungus on muzzles or wings. Do not handle bats. Call the DNR toll-free Animal Report Line at (888) 345-1730 or go to www.mndnr.gov/reportbats.