Disease sucking life out of bat population

By MARIBETH WARD, Staff Writer

First the honeybees were afflicted with a mysterious ailment and now bats are dying. An unprecedented die-off of thousands of hibernating bats in the Northeast has caused biologists and researchers from around the country to try to determine the cause, and to assess the threat to bat populations nationwide.

The disorder, dubbed white-nose syndrome (WNS) because of the presence of a white fungus around the muzzles of some affected bats, is a major concern to the bat conservation community.

Most bats with WNS are little brown bats, but endangered Indiana bats have also died, raising concerns about the impacts on a species already at risk. Other affected bat species include the Eastern Pipistrelle, the Northern Long-Eared bat, and the Small-Footed bat.

The syndrome was first detected at caves and mines in New York last winter, where it is believed to be associated with the deaths of approximately 8,000 to 11,000 bats.

This winter, WNS was again been found at the previously affected sites, and has spread to additional sites in New York as well as sites in Vermont, Massachusetts and Connecticut. Approximately 400,000 to 500,000 bats hibernate at affected sites.

Researchers know there is a serious problem -- hundreds of thousands of bats have died as a result -- but they are still baffled by the disease. The fungus is clearly associated with white nose syndrome, but scientists still do not know whether it is causing the disease or simply a symptom of a virus that has yet to be identified.

David Blehert, a microbiologist with the U.S. Geological Survey's National Wildlife Health Center in Madison, Wis., explained that the dead bats are found only at caves where bats hibernate. Bats tend to stay in hibernation through the end of April, so researchers need to use the next two months to collect whatever information they can.

What is more troubling to Blehert is the disease's ability to spread. Imagine a contaminated cave being the center of a bull's eye. The target itself would extend about 150 miles in all directions from the cave.

Indiana bats, protected by the federal Endangered Species Act as well as state laws, range across much of the eastern United States. Indiana supports the largest hibernating population of the species. About 238,000 Indiana bats, approximately 46 percent of the total population, winter in Indiana caves. Another 15 states have populations of hibernating Indiana bats.

Indiana State University's Center for North American Bat Research and Conservation has established a fund for research and response activities related to WNS. Information is available at www.indstate.edu/ecology/centers/bat.htm

In addition, Bat Conservation International has established a Fund for White-nose Syndrome Research. Information is available at www.batcon.org

The U.S. Fish and Wildlife Service is working closely with the affected states, where biologists are investigating the geographic extent of the outbreaks and collecting samples of affected bats.

They are developing a geographic database to track the location of sites where WNS has been found, and are collecting information at each site, such as the number of bats affected.

This information will be critical in tracking the extent and spread of WNS and in coordinating research efforts. The Service is also partnering with the Northeastern Cave Conservancy to track movements of cavers who have visited affected sites in New York www.necaveconservancy.org

Fish and Wildlife Services have asked cavers to observe all existing seasonal cave closures at known Indiana bat hibernacula, and when possible, to avoid caves or passages of caves containing large hibernating populations of any bat species.

While caving, anyone who observes a hibernating bat with a white muzzle or other odd white, fungus-like patches should follow the guidelines below.

* Do not touch any bats (living or dead), especially those with a white muzzle/nose.

* If you have a camera with you, please take a few photographs of the potentially affected bat(s).

* Exit the cave immediately, avoiding contact with other bats, and please do not enter any other caves prior to reporting your potential WNS observations to your state fish and wildlife agency or your nearest U.S. Fish and Wildlife Service Field Office.

* Anyone who observes any unusual numbers of bats outside during cold weather, especially near a cave or mine where bats hibernate, is asked to report those observations as well. An increased number of bats flying outside and increased reports of dead bats in the vicinity of hibernacula have been observed in affected areas in the Northeast.