Little brown bats are under attack from a cold-loving fungus

Fight back for bats under attack

B.c. bats might soon be facing a fungus decimating populations out east.

White-Nose Syndrome (WNS) has come to North America, and has been killing bats in vast numbers ever since its arrival. The fungus first came to New York state, or at least was first noticed there in 2006.

A caver, someone who explores or studies caves, discovered a group of hibernating bats (also known as a hibernaculum) near Albany, NY with something white on their muzzles. The explorer also noticed several dead bats lying on the floor of the cave. It was during the next winter that erratic bat behaviour and the white muzzles were noticed by local biologists, who put the two together. Since then, over a million bats have died from the disease, mainly in eastern North America.

White-Nose Syndrome is caused by a fungus that grows on cold bodies, bat researcher Cori Lausen informed the Arrow Lakes News. The bats must come out of hibernation to groom and fight off the fungus, which in turn burns off their fat stores. Feeling the pinch, some bats not used to fly during the winter months will leave their hibernaculum searching for food, using up more precious energy. Death by starvation is what kills bats afflicted by WNS.

Bat hibernacula are typically much larger in eastern Canada, which has lead to the rapid spread of WNS there. According to the U.S. Fish and Wildlife Service WNS webpage, 90 to 100 per cent of bats are dying in the eastern states, and now the worry is that the fungus will spread to the other side of the Great Divide and decimate western bat populations as well.

One saving grace for western bats is that their hibernacula are generally smaller in size, said Lausen. The largest hibernaculum in western North America is a group of 3,000 bats in the Northwest Territories, she detailed, whereas the largest hibernaculum discovered in B.C. had only 40 individuals.

It has now been confirmed that the fungus was brought over from Europe by cavers, said Lausen. It is believed that European bats suffered a “bottleneck” extinction event, thanks to the fungus, which destroyed most of the bats there a few thousand years ago. All bats in Europe are now classified as endangered and protected by law.

Cavers are now well aware of the fungus and are “on board” with efforts to prevent its spread, said Lausen. Unfortunately, amateur spelunkers and geocachers aren’t as well educated yet, she added, which is why she is keen to get signs posted near old mine shafts and caves teaching people about WNS and asking them to think twice before entering delicate bat habitats.

Lausen was recently awarded a grant from the Habitat Conservation Trust Foundation to continue her research on bats throughout southern B.C. She has also received funding from the Columbia Basin Fish and Wildlife Conservation Trust that made another year of her research possible. From Cranbrook to Vancouver Island Lausen and her team of volunteers will be monitoring bat populations, with many of the bat catchers right here in the Kootenays.

One effort to slow the spread and the effect of WNS that people can get involved with is building houses for the small, furry flying mammals. Bat houses not only provide good habitat for the Chiropteran set, they also make it easy to monitor them for WNS. Not only that, but the people-made habitats encourage the insect-eaters to live nearby and eat up mosquitos and other pesky flyers that roam the air at night. Who wouldn’t want them as neighbours?