NEW YORK -- Disease has killed more than 90 percent of some bat populations in Northeastern states, according to a survey released yesterday by the New York State Department of Environmental Conservation.

The DEC survey in New York, Connecticut and Vermont examined 23 caves that are believed to have once been home to more than 55,000 bats, roughly 10 percent of the regional bat population.

The culprit is "white-nose syndrome," an ailment named for a white fungus found on afflicted bats. DEC researchers found that populations of the most common regional species, the brown bat, had declined 93 percent on average.

A separate survey of an endangered species, the Indiana bat, showed it had declined 53 percent on average, researchers reported.

Allen Hicks, the New York agency's bat expert, said colder and drier areas preferred by the Indiana bat may be helping it to avoid a fate as severe as that affecting the little brown bat. The state report says a population of Indiana bats found hibernating in a warmer and wetter abandoned mine was down by 97 percent, while another in a cooler and drier mine in the same county had declined by 27 percent.

The fungus associated with white-nose syndrome, Geomyces destructans, is suspected to be at the heart of the problem, though officials caution that this has not been conclusively proven. Studies show that bats with the white fungus on their noses use all their fat reserves months before hibernation ends and starve to death.

The disease seems to spread quickly when bats congregate in large numbers for winter hibernation. DEC says that it still does not know from where or how the infection originated. White-nose syndrome was first discovered in upstate New York during the 2006-2007 winter.

The recent DEC study was conducted with the U.S. Fish and Wildlife Service and a number of other state agencies and volunteers. Researchers are gearing up for another round of cave inspections next month to determine how much the epidemic has progressed thus far in the current season.

"Researchers from around the country are focusing on the bat die-off and DEC will continue to work with a wide range of partners to try to get to the heart of the problem," DEC Commissioner Pete Grannis said in a release.

The Fish and Wildlife Service is funding research bent on finding the cause of white-nose syndrome and possible solutions. Scientists are trying to determine whether environmental contamination may be associated with the disease and at the same time are studying possible ways to halt the spread of the fungus among bats.

Reprinted from Greenwire with permission from Environment & Energy Publishing, LLC., 202-628-6500