(WAYNESVILLE) -  The dropping temperatures will force many species of bats into their caves for the winter - and, this year, they have something to fear. White Nose Syndrome has spread to North Carolina, already killing at least 5 million cave-dwelling bats in the northeastern states. Gabrielle Graeter, biologist with the North Carolina Wildlife Resources Commission, says having fewer bats will affect everyone.

"It's really incredible the service that the bats provide by eating so many insects - and if we don't have bats to eat those insects, then we have to use a lot more pesticides. "

White Nose Syndrome is spread from bat to bat and first appeared in eastern New York in 2006. The disease causes a white fungus to appear on the bat's nose, wings, ears or tail. White Nose has been found in Transylvania, Haywood, Avery, Yancey and McDowell counties, but cases also are suspected in Rutherford and Buncombe counties.

An artificial bat cave is open in Clarksville, Tenn., to provide a sanitary winter habitat in an attempt to save the animals. Graeter says winter is when most bats are exposed to and die from the disease because of their close quarters inside the caves.

"They're just sitting ducks. Their bodies are shut down. Their immune system is shut down to some degree, and they're sitting there, vulnerable. They're cold, and the fungus just gets a chance to grow all over them."

A recent study suggests that the loss of bats in North America could lead to agricultural losses estimated at more than $3.7 billion a year, nationwide. State and federal biologists are working to determine the source of White Nose Syndrome and what can be done to save the bat population.