Biologists are warning of the potentially devastating impact White Nose Syndrome (WNS) could have on British Columbia's bat population after the deadly infection was detected in Washington state.
Officials confirmed the first recorded instance of the syndrome in western North America this March, when the disease was detected in a dead bat outside of Seattle. Given the migratory pattern of the infected subspecies of little brown bat extends along the coast from Washington state up to Alaska, Whistler biologist Bob Brett believes it's "almost inevitable" the disease will reach B.C.
"The closest analogue, I'd say, is the mountain pine beetle. And the thought was the mountain pine beetle epidemic would not cross the Rockies, in this case from west to east. But of course it did," Brett said. "There's really no reason why (WNS) wouldn't do the same."
White Nose Syndrome is a quick-spreading fungal infection that affects the muzzle, ears and wings of hibernating bats. It has killed six million bats in five Canadian provinces and 28 U.S. states since it was first recorded in eastern New York 10 years ago.
"(WNS) causes the bats distress in the winter, so they end up having to come out of hibernation and spend some of their resources during the winter to resist the fungal infection. That means they deplete a very limited resource of energy over the winter that they need in the spring. The problem is, because they're colonial, the fungus can affect pretty much the whole population. When you've got 95-per-cent lost each year, it doesn't take long before you don't have a colony,' Brett said.
Scientists originally believed the disease would remain confined to eastern North America and are now scrambling to better understand the potential impacts it could have on the 14 species of hibernating bats found in British Columbia. (Nine bat species have been officially recorded in Whistler.) The provincial government is encouraging the public to report the location of any unusual bat activity, including bats flying during the day, or finding dead or dying bats.
"It is a race against the clock now to see if we can study enough of the species to predict impact," wrote Cori Lausen, a bat specialist with Wildlife Conservation Society Canada, in an email.
"If we can determine which are at highest risk, then we will be able to properly allocate conservation resources (and possibly apply potential mitigation strategies) and highlight priority management actions."
Based on what has been seen so far in the east, Lausen said bats belonging to the genus Myotis would be most at risk in British Columbia. Eight Myotis species are found in B.C., accounting for half of the bat species in the province, including the endangered Little Brown Myotis and Northern Myotis.
One of the challenges at this point is that researchers still don't know if the strain of White Nose Syndrome found near Seattle is the same one that has decimated bat colonies further east.
"Within the next month or two we should know if the strain of fungus in Washington is the same strain as in eastern North America," Lausen said. "If that is not the case, then we will have the added uncertainty of not knowing if this western strain will behave the same way or may have different conditions for optimal infection. There are a lot of questions and not many answers at this stage in the game."
Now Lausen is teaming up with cave explorers to help locate winter roosts and get a better handle on B.C.'s bat population through a program, BatCaver.org, largely funded by Environment Canada.
"Because WNS kills bats in winter while they hibernate, locating (roosts) is pivotal to documenting impacts of WNS and potentially being able to help bats survive," said Lausen.
Often working with limited resources, Lausen said researchers are working to fill in some of the "daunting" gaps in knowledge that exist around B.C.'s bats — except now they don't have the luxury of time on their side.
And while it's difficult to predict the exact impact WNS may have, the consequences of a major population decline are expected to be far-reaching.
"If any of our bat species decrease significantly, we are likely to see downstream effects," Lausen noted, highlighting bats' important role as the primary consumer of night-time insects, including disease-spreading mosquitoes, as well as moths and beetles, which can cause major damage to forest and crops. "Bats are estimated to be worth billions of dollars to the corn industry alone in the U.S., and so we can only assume that there will be economic ramifications of WNS here in Western Canada also."
British Columbians can contact the BC Community Bat Program at 1-855-922-2287 to report any bat sightings. For more information on WNS, visit www2.gov.bc.ca/gov/content/environment/plants-animals-ecosystems/wildlife/wildlife-health/wildlife-diseases/white-nose-syndrome.