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Canwest News Service
Brock Fenton shudders when he thinks of a world without bats.
For more than 40 years, Fenton — a professor at the University of Western Ontario and Canada's foremost bat expert — has been visiting an abandoned mine 75 kilometres west of Ottawa near Renfrew, Ont., where bats hibernate by the thousands.
Fenton knows that one day soon they may all be gone, killed by a lethal fungus that is destroying the bats of eastern North America.
It's called white-nose syndrome and since its appearance less than four years ago, it has killed, by some estimates, more than a million bats in the Northeastern U.S.
Earlier this year, a group of leading U.S. scientists from 12 states and federal wildlife agencies warned that the disease "has caused the most precipitous decline of North American wildlife in recorded history."
"The whole thought of going into that mine and there being no bats — it's hard to imagine," says Fenton, a former Carleton University professor who first visited the Renfrew mine in 1965.
"Maybe we're just going to have to get used to it."
Bats are prodigious consumers of insects, but no one know what the potential loss of bats will mean in Ontario, Fenton says. Too little is known of their numbers or their feeding habits.
It was just three winters ago that biologists in New York State began to hear strange reports of bats flying around in broad daylight in the dead of winter. When they entered an abandoned mine in the Adirondack Mountains that was a known bat hibernacula — a site where bats hibernate — they were shocked to find it filled with starving bats, their muzzles coated in a fine white fungus. When word got out about the disease they called white-nose syndrome — WNS — cavers sent them photographs from a year earlier in a cave near Albany, N.Y., that showed other bats suffering from WNS. Those photos are the first known incidence of a disease that has since spread throughout the northeast states and as far south as Virginia.
WNS has been confirmed in Watertown, N.Y., 30 kilometres from the Ontario border, as well as in border states Vermont and New Hampshire. In some cases, the disease has killed between 90 and 100 per cent of the bats in an infected hibernacula.
Al Hicks, the man at ground zero for white-nose syndrome, believes the Little Brown Bat, the most common bat species in Ontario, will be wiped out within 10 years.
"Two years ago, at one site in New York, we counted 200,000 bats," said Hicks, a mammalian biologist with the Department of Environmental Conservation in New York state. "It was the largest colony of Little Brown Bats in the world. When we went in last winter, we found 3,000."
The die-off has been so rapid, Hicks said, that ornithologists from Cornell University, who were enlisted to photograph and videotape bats for research purposes, now have a new motivation — to make a record of the species before it disappears.
So far, WNS has not been confirmed in Ontario. Last summer, biologists with the Ministry of Natural Resources visited nine hibernacula in southwest Ontario near the U.S. border that they considered most at risk. They found nothing.
John Dungavell, a disease policy expert with the ministry, won't speculate on what WNS will mean for Ontario bats, but said there is cause for concern.
"It looks like the majority of our population is fairly healthy," Dungavell said. "Based on how quickly and far it's spread in the U.S., we have to be vigilant."
The same is true in Quebec, where a survey last winter of three hibernacula turned up nothing.
"We haven't had any documented cases, but that doesn't mean it's not there," says Julien Mainguy, a biologist with Quebec's Ministry of Natural Resources and Wildlife.
"All we can do is wait. There's no solution to this problem."
Mainguy said he's received reports from a caver who thought he'd seen the fungus on a bat in Lafleche Caverns, north of Ottawa, but when biologists went to check, they found no sign of bats. Mainguy hopes to return there this winter to look for the fungus.
Little is known about how WNS kills bats. U.S. studies show it to be a never-seen-before fungus — Geomyces destructans — that grows only in the cold, and they draw parallels to the fungus that is blamed for the worldwide decline of frogs and other amphibians. Though it is most apparent on the muzzles, the fungus can grow anywhere on the bats' bodies, including their fragile wings.
Hicks says the latest research shows the fungus is similar to one known to infect bats in Europe. He suspects spores hitchhiked to North America on a traveller: The first occurrence was in a branch of Howe Cavern, a commercial cave in New York visited by 200,000 tourists every year.
Curiously, European bats seem to be able to survive the fungus. But Europe's bat population is smaller than North America's. Whether North American bats will adapt and stabilize is anyone's guess.
Nor is it known if it's the fungus itself that kills the bats, or if it is just a symptom that appears when the animal's immune system is compromised.
What is clear is that WNS disrupts bats' hibernation. Bats hibernate from about September to April, typically massing in caves or abandoned mines in groups of from several hundred to tens of thousands.
Normally, a bat will rouse from its torpor once a month or so in the winter. WNS disrupts that pattern, waking bats continually during the winter and depleting their energy as they struggle to bring their body temperature back up from near freezing. Witnesses in WNS areas of the U.S. report seeing dying and emaciated bats floundering about during daylight in mid-winter, dehydrated and desperate for a meal of insects that can't be found.
Scientists in the U.S. have been monitoring the spread of WNS almost since it was first identified. They have been trying to find a way to inoculate bats to protect them from the disease.
WHAT YOU CAN DO
– Bats are most vulnerable during hibernation. No one should enter a hibernacula between September and April or into a bat nursery cave during the breeding season in mid-July.
– If you see bats outside in daylight or in winter, it may indicate the presence of WNS. Report it to MNR. In rare cases, bats can also be infected with rabies, so take care.
– Those who venture into caves should clean and disinfect their clothes and equipment afterward. Technical gear, such as ropes or harnesses, that can't be cleaned easily should be dedicated for use in one cave only.
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