Disease continues to decimate bats in western NC, surveys show

A fungal disease is still decimating bats in western North Carolina more than a decade after it was first detected in the eastern U.S., surveys by state biologists show.

White-nose syndrome had been previously found only in the western part of the state, where most caves and mines that bats use are found. But surveys done in January and February also documented it in the Piedmont.

Four tricolored bats in Stokes County, on the Virginia line due north of Charlotte, were seen with the whitish, fuzzy fungus growing on their noses, wings and ears. The disease is fatal.

Bats are important animals because they feed on insects, including crop and forest pests, pollinate plants and spread seeds. The U.S. Geological Service estimates that loss of bats in North America could lead to agricultural losses of more than $3.7 billion a year.

But the low numbers of bats the recent surveys found indicate that “large declines in bat populations have already occurred,” the North Carolina Wildlife Resources Commission says.

“What we’re seeing now at these sites is (the disease’s) devastating aftermath,” mammalogist Katherine Caldwell said in a commission release. “Most sites we surveyed in western North Carolina had over 90 percent declines in bat populations from their pre-WNS counts, with some declines as high as 99 percent.”

Bats in the Piedmont and coastal plain appear to be faring better. State biologists found the highest number of bats at two sites that have been monitored for four years, and bats found in an coastal Onslow County cave appeared to be free of the disease.

White-nose syndrome was first detected in North Carolina in 2011, in Avery County. Since then, the disease has spread to 10 western counties and has likely spread throughout the mountains.

The fungus has been found in eight bat species but has hurt four species – northern long-eared, little brown, tricolored and Indiana bats – the worst. It’s not known why some species are affected more than others.

While the fungus grows readily in cool, humid caves and mines, it has not affected bats that roost in trees. State biologists are looking for more mines and caves to survey, and ask that willing property owners contact Caldwell at katherine.caldwell@ncwildlife.org.

This story was originally published June 2, 2017 at 11:50 AM with the headline "Disease continues to decimate bats in western NC, surveys show."