This coverage is made possible through a partnership between BPR and Grist, a nonprofit environmental media organization.
North Carolina researchers have sighted and caught a significant number of Indiana bats in western North Carolina for the first time in ten years. This federally endangered species was nearly wiped out in the state by disease, but they could make a comeback.
North Carolina Wildlife Resources Commission bat researchers sighted twenty-four bats in Graham County, roosting in a dead hemlock tree in the Joyce Kilmer-Slickrock Wilderness. According to Gabrielle Graeter, the Western Wildlife Diversity Supervisor for NCWRC's Wildlife Diversity Program, the tree is a maternity site where bats gather to have their babies.
Many Indiana bats have fallen prey to a deadly fungal disease, called white nose syndrome. White nose syndrome has killed an estimated 90% of three bat species in infected caves in North America, and has severely reduced populations of the Indiana bat. It causes bats to wake up early during hibernation, using up the energy stores they need to get through the winter, according to the U.S. Fish and Wildlife Service.
Gabrielle Graeter said this disease threatened to wipe out the North Carolina population. There weren’t many in the region to begin with. “Indiana bats were really on the edge of their range,” Graeter said. “Before white nose syndrome arrived, we didn't find a lot of them, but it was not uncommon to find one or two or a few here or there.”
The NCWRC’S bat research involves intensive monitoring which includes mist nets that can capture bats, wintertime cave counts, and even acoustic monitoring, which can record and identify bat calls that are undetectable to the human ear. It’s through mist netting that the agency’s researchers were finally able to capture the Indiana bats.
Graeter said that this sighting is a hopeful indicator of recovery, but not a sure one.
“The ones that survived may, you know, be more able to withstand white nose syndrome in some regard and we don't really have answers to that yet on why,” Graeter said.
Climate impacts like flooding and extreme heat have also played a role, Graeter said. Helene knocked down trees that bats use to roost, and swings in temperature have affected the insects they rely on for food.
Jesse de la Cruz, a researcher who studies bats at Virginia Tech, told BPR that Indiana bats are in danger across the Appalachian region almost entirely due to white nose syndrome. Indiana bats have survived repeated assaults on their habitat, from the logging of the early 20th century to increased development in the South and industrial agriculture across the Midwest, he said.
Indiana bats will rotate through a network of dead trees in a given area, he said, and they like to be high up above the tree canopy, to be warm and access more sunlight.
“They kind of form nomadic colonies whereby they find that next clump of dead trees,” said de la Cruz, and the bats do so over and over again.
“These animals form these tight-knit colonies that are pretty much all females,” de la Cruz said. “And that group is often then grandmothers and mothers and sisters and aunts that rear that rear these young and then their young will often return either to that area or very nearby over decades.”
