A bat in Washington state recently tested positive for the fungus that causes white-nose syndrome (WNS), leading scientists to believe the disease may be more widespread than originally thought.
The fungus, known as Pseudogymnoascus destructans (Pd), was found on a silver-haired bat in King County, the same area a group of hikers discovered a little brown bat infected with WNS in March. Before then, scientists believed the syndrome had not moved farther west than Nebraska.
"I think we ultimately still don't know how the disease may manifest in the West with the different climate and different hibernating conditions, but it does indicate the disease is more widespread than just a single incident," noted David Blehert, chief of the Wildlife Disease Diagnostic Laboratories Branch in Wisconsin.
Although the bat did not show symptoms of WNS, the finding added further proof to the theory that the silver-haired bat may be a carrier of the disease, which has devastated colonies in the eastern U.S. and Canada.
Although some have warned of the risk of the silver-haired bat spreading the Pd fungus, the reality, explained Cori Lausen, bat specialist for Wildlife Conservation Society Canada, is that the species' migratory patterns seem to differ in the West.
"When you look at the silver-haired bat in any kind of reference to North America, it's going to be listed as a long-distance migrating bat, and that's because in the East, they do seem to do that," she said. "But here in the West, we're starting to very recently understand that our silver-haired bats are likely not these long-distance migratory bats. So for us, we have this different perspective in that we don't think the silver-haired bats are going to spread this fungus any more than any other species."
That doesn't mean there isn't cause for concern, however. Although the fungus has yet to be recorded in British Columbia, scientists say it's likely only a matter of time.
"There is potential that it's already in B.C. or closer to the border than we know," said Jeremy Coleman, national white-nose syndrome coordinator for the U.S. Fish and Wildlife Service.
"It definitely is a considerable risk," added Lausen, who said that even with the silver-haired bat's shorter migrations, there is a strong likelihood the disease will cross the border.
"Knowing the ecology of these bats and hypothesizing what direction their migration might be, especially along the coast, we would expect a north-south migration. And so the chance of the fungus reaching at least southwestern British Columbia, I think is quite high."
White-nose syndrome is a fungal infection that causes bats to develop white patches on their muzzles, ears and wings during hibernation.
The first detected case of WNS in North America was in eastern New York in 2006; the disease surfaced in Canada in 2010. It has killed more than 6 million bats in five Canadian provinces and 28 American states.
Even with those staggering numbers, Lausen said it's important not to write off Canada's bats too quickly.
"What's become a bit of an issue, even within the government itself, is that some people are feeling like, 'our bats are doomed, I guess there's nothing we can do.' That is so wrong," she said. "The problem with thinking that way is that this is probably going to spread very slowly. If we assume that it's already been here for a year or two, we can assume that it's spread slowly throughout the province because our bats don't move these long distances. So we may actually have more time than we think."
The challenge for researchers now is a lack of government funding for bat research.
"Unfortunately the (B.C.) Ministry of Environment has not only cut back on funding but reneged on the funding they were supposed to have provided," Lausen said. "It's pretty serious, in fact, I'm in the process of writing a letter to the minister because this is completely unacceptable when you have this large a number of species at risk and we can't get funding to even do the smallest of things."