4 dead little brown bats test positive for WNS
May 26, 2010
BRETTON WOODS — The presence of white-nose syndrome (WNS) has been confirmed in four little brown bat carcasses collected in March along the
Base Road between Route 302 East and the Cog Railway.
Wildlife disease specialist Anne Ballmann, DVM, Ph.D., at the National Wildlife Health Center in Madison, Wisc., recently forwarded the bad news to Emily Brunkhurst at the state Fish and Game Department.
Increased daytime bat flights were noticed in early March around the base of west-facing slopes of Mt. Washington by retired U. S. Forest Service forester and avid bird-watcher Dave Govatski of Jefferson, backcountry skier Carl Brown of Whitefield, and several others. About 33 dead little brown bats were seen, although the death toll apparently could be as high as 100 bats along a seven-mile stretch of road. Because scavengers quickly removed or fed on carcasses, making an accurate count impossible.
A total of 17 dead bat carcasses were collected in late March, of which four carcasses were sent to the Wisconsin lab for diagnostic evaluation for white-nose syndrome (WNS).
Wing tissues from all four bats tested positive for Geomyces destructans, the presumptive causative agent of WNS.
These bats are considered "presumptive positive" for WNS because of suspect field signs, including unusual day-flight activity, mortality, and closeness to other WNS locations.
U. S. Fish and Wildlife Service experts as well local birders and wildlife enthusiasts believe that an undiscovered bat cave could be on mountain slopes, and efforts will continue to be made to find one or more.
"I'm really sorry that our worst suspicions were confirmed," Mr. Govatski said. "I'd much rather have been proved wrong."
Hibernating bats in the northeastern U. S. are dying in record numbers, and the cause of their deaths is not known.
White-nose syndrome is named for the appearance of the muzzles and wings of affected bats, according to a USFWS bulletin.
WNS was first documented at four sites in the winter of 2006-07 in eastern New York. WNS has rapidly spread to multiple sites throughout the northeast.
Researchers associate WNS with a newly identified fungus — Geomyces — that thrives in the cold and humid conditions that characterize the caves and mines used by bats.
The fungus could be responsible for the bat deaths, or it could be secondary to the cause experts say.
Bats affected with WNS do not always have obvious fungal growth, but they may display abnormal behavior both within and outside of their hibernacula — the caves and mines where bats hibernate during the winter.