Massachusetts and Vermont wildlife officials are asking the public to help identify bats affected by a mysterious illness known as white nose syndrome.

This time of year, bats are normally hibernating in caves and in abandoned mines across the Northeast. But researchers are getting reports of bats weakly flying around in broad daylight or dying on decks and in backyards. Scientists believe the bats are leaving caves to find food, but are dying first.

The illness was first seen two winters ago, when thousands of bats died in four New York caves. Many had an unusual white fungus on their nose and bodies that gave rise to the name white nose syndrome. By last winter, 25 caves and mines were found to have sick or dying bats in Massachusetts, Vermont, Connecticut, and New York.

"Citizens living near caves or mines with affected bats are witnessing unusual levels of activity and mortality of these animals," says Vermont Fish & Wildlife Department biologist Scott Darling.

"This type of behavior is occurring even earlier than last year, perhaps because white nose syndrome has further compromised the health of our bat populations," he said.

Environmental officials ask that residents who see dead or dying bats - or observe them flying around in the daytime - call MassWildlife at 508-759-3406. In Vermont, residents are asked to go to www.vtfishand wildlife.com and click on the Sick-acting Bat Citizen Report Form, or call 802-786-0055.

While the syndrome is not considered dangerous to humans, people should not handle the animals unless necessary, and then with gloves or tools.