By Sean Willett
The most common species of bat in North America is now threatened with possible extinction — and there is little hope of stopping it.
A disease known as White Nose Syndrome has been sweeping across the United States and Canada, killing hibernating bat species by preventing them from maintaining a dormant state during the winter. Recent surveys have placed the number of bats killed at around six million, with a mortality rate of over 90 per cent.
Professor of biological science at the University of Calgary Robert Barclay explained that while the disease has not yet reached Alberta, it is only a matter of time.
“This is already an ecological disaster,” he said, “and when it reaches Alberta it will definitely have an environmental impact.”
While the spread of the fungus-based White Nose Syndrome seems inevitable, it may still be several years until it reaches the Rockies. With the infected zone growing annually by about two states, Alberta should have around five years before the disease reaches its borders.
Preventative measures in the United States and the natural barrier provided by Saskatchewan’s prairies might also play a part in further slowing its spread.
White Nose Syndrome originated in Europe, where the native bats are resistant to the virus. The disease was accidentally brought to New York in 2006, and has been spreading westward across the continent ever since.
Scientists and government officials are making sure to use this time wisely.
U of C biology graduate student Jesika Reimer is working in Wood Buffalo National Park to help establish a baseline population count of the three bat species native to northern Alberta, one of which is the little brown bat, the species that is most susceptible to the disease.
“Getting an idea of what the baseline population is like, what the health of the population is and some other basic knowledge will be really good in getting to know what effect White Nose Syndrome is going to have,” she said.
Additionally, Reimer is studying the adaptations bats are using to survive the northern climate.
“If the bats are doing anything different up north, their behaviour may be different in such a way that White Nose Syndrome may not affect them,” she said, “or maybe it could even affect them in a more detrimental way.”
The possibility that northern bat populations will be able to survive the disease is encouraging, but the Albertan government and Parks Canada are not taking any chances.
To prevent humans from spreading the fungus that causes White Nose Syndrome from one bat cave to another, regulations are being enforced to restrict public access to bat caves. Only individuals with permits are now allowed to enter, and even then only after a thorough decontamination.
Reimer, however, is unconvinced that these regulations will help. “If someone is out hiking and they happen to find a cave, it’s pretty hard without gates or signage to keep them out,” she said. Compounding this difficulty is the spread of the fungus through the bats themselves. “You can’t tell a bat not to go into a non-infected cave.”
Despite its challenges, there are few options besides prevention to protect North America’s remaining hibernating bat populations.
So far efforts to develop a cure have been unsuccessful, with the use of fungicides ruled out due to the environmental damage they would cause. While heated food boxes may provide a temporary fix to help affected bats survive the winter, they are not a feasible long-term solution.
With species such as the once-prolific little brown bat being considered for the endangered species list, the public is beginning to take notice, which can help to combat White Nose Syndrome.
“This issue has been getting a lot of attention, which is good, since bats usually don’t get a lot of press unless they do something bad,” said Barclay. “They aren’t exactly cute and cuddly.”