The White-Nose Syndrome Mystery:
Credit: Al Hicks, New York Dept. of Environmental Conservation
Tens of thousands of hibernating bats died this winter in the northeast, and we don’t know why. In and around caves and mines in eastern and upstate New York, Vermont, western Massachusetts, and northwestern Connecticut, biologists found sick, dying and dead bats in unprecedented numbers. In just eight of the affected New York caves, mortality appears to range from 80 percent to 100 percent since WNS was first documented at each site, based on winter surveys.
These bats often have a white fungus on their muzzles (hence the name “white-nose syndrome”) and other parts of their bodies. Despite the continuing search to find the source of this condition by numerous laboratories and state and federal biologists, the cause of the bat deaths remains a mystery.
Bats are an important part of our ecosystem. One bat eats as many as 3,000 flying insects a night during the summer months. Because females produce just one pup a year, the plunging number of bats — apparently as many as 90 percent loss in some hibernacula — translates into a crisis in bat populations in four states with no end in sight and potentially far-reaching effects, an ecological disaster in the making. This year we may notice an absence of bats from our summer night sky, and what will that mean for us?
At least one of the affected species, the Indiana bat, is protected by the Endangered Species Act. Little brown bats are sustaining the largest number of deaths. Also dying are northern long-eared and small-footed bats, eastern pipistrelle and other bat species using the same caves.
Biologists are still not certain if the bats are transmitting white-nose syndrome among themselves, or if people or both bats and people are spreading it. Affected dead and dying bats are generally emaciated, and those found outside are often severely dehydrated.
|Credit: courtesy of Cal Butchkoski, Pennsylvania Game Commission|
At the beginning of April 2008, we had identified white-nose syndrome in 18 sites in New York; five sites in Vermont; three sites in Massachusetts; one site in Connecticut; and three possible sites in Pennsylvania. The states of New York, Vermont, Connecticut and Massachusetts are investigating the geographical extent of the outbreak, revisiting sites to determine the amount of mortality, and providing bat specimens to laboratories throughout the United States for analysis to help determine the cause of bat deaths.
The bat conservation community is concerned and involved in exploring the possible cause of the disease and raising funds to assist in the research. National and regional caving organizations are coordinating with state biologists to help assess the situation, providing the most current information to the caving community regarding advisories, and documenting cave visitations to determine if cavers could be spreading the cause of the outbreak.
If you have observed potential signs of white-nose syndrome in bats during a caving trip, or if you have dead or dying bats in your area, send information to us.
Bats with this white-nose syndrome have the white fungus on their noses and occasionally other parts of their bodies. It is unknown if the fungus is causing the deaths or is symptomatic of a disease. The fungus isn’t always visible to the naked eye — and rarely is it visible on bats found flying or dead outside of their hibernacula.
Several different fungal species were identified from various skin samples from New York bats, both with and without external signs of fungal growth, according to the U.S.G.S. Wildlife Health Center in Madison, Wis. The fungi including a number of species in the Penicillium genus and others, including Alternaria spp., Aspergillus niger, Pestalotiopisis cocculi, and Geomyce spp. There does not appear to be fungus inside the body of the bats other than sebaceous glands.
Human health implications are not known; there is no information indicating that people have been affected after exposure to the white fungus.
This week state and Service biologists are:
- Planning a meeting for state and federal biologists, researchers and invited scientists to coordinate future investigations into the cause and spread of WNS;
- Responding to inquiries from the news media;
- Coordinating with the caving community for summer caving decontamination protocols in affected states; and
- Documenting reports of abnormally behaving or dead bats, following up with phone calls, e-mails, site visits.
- Laboratory examination of bats from caves and mines in Kentucky and Wisconsin found no signs of WNS;
- Protocols updated for collecting sample bats using mist nets;
- Made presentations at the Northeast Fish and Wildlife Conference on white-nose syndrome;
- Working on alternate sources of funding; and
- Continuing to receive reports from the public of dead and dying bats in New York, Massachusetts, Vermont and New Hampshire.
What can you do to help?
The Service is partnering with the Northeastern Cave Conservancy to track movements of cavers who have visited affected sites in New York, Massachusetts and Vermont. If you have visited Knox, Schoharie, Gages or Hailes caves in New York, the conservancy asks you to visit its site to complete a Trip Visitation Form for WNS Study.
Indiana State University Center for North American Bat Research and Conservation has established a fund for research and response activities related to white nose syndrome.
Bat Conservation International has likewise established its Fund for White Nose Syndrome Research.
Message to Cavers
The Service applauds the caving community’s strong conservation ethic and long-time support of bat conservation efforts, and we ask for your continued cooperation and assistance as we and our state and nongovernmental partners work to address white–nose syndrome. We request that cavers observe all cave closures and advisories and avoid caves or passages of caves containing large hibernating populations of any bat species. The Service discourages cavers or caving groups from systematically searching for bats with white–nose syndrome in caves or mines. Note that not all affected bats have fungus that is easily visible.
Research and Surveys
White-nose syndrome is such a recent occurrence that very little research has been published. We are still analyzing bats and looking at a variety of possible causes. We hope to have a general summary of what has been investigated within the next few months. The spring 2008 issue of “Bat Research News” has an article “Current Status of White-nose Syndrome in the Northeastern United States” by Jacques Pierre Veilleux, but the article is not available online.