Bat populations in Ontario and beyond are dwindling — a result of disease and killer wind turbines. But bats are ugly nocturnal beasts and the stuff of many people’s nightmares. So why should we care?
Roughly 7 million bats in North America have died from white-nose syndrome since it first appeared on the continent around 2005. Caused by a fungus that grows on certain species of bats, the disease is believed to disrupt hibernation: Some infected bats expend too much energy and die before spring. Others emerge from hibernation weak and less able to hunt and reproduce. Infected bats were recently found in Kenora, meaning it has now spread westward right across Ontario, says biologist Craig Willis of the University of Winnipeg.
“Where we know where bats hibernate, we know it’s been found,” he says.
Wind turbines also contribute to the problem, killing hundreds of thousands of migratory bats across North America every year, Willis says.
Many of these deaths are avoidable. Willis is involved with the Neighbourhood Bat Watch Program, which tracks populations across several provinces and is experimenting with ways to help bats affected with white-nose syndrome. It builds heated boxes for the animals to roost in during the summer, for example — pups that are kept in warm roosts grow more quickly, and bigger pups have a better chance of surviving their first winter.
Brock Fenton, professor emeritus of biology at Western University, says studies show that wind turbines and bats can happily co-exist if the machines are run only when wind speeds rise above 10 metres per second: bats can’t fly when it’s that blustery. Turning off turbines when bats are present or locating wind farms away from bat colonies would also make a significant difference.
Still, getting widespread support for programs in aid of an animal most people find downright creepy is tough. “This is a public relations nightmare,” says Fenton. “Because the average person doesn’t care about a species of plant or animal or yeast or anything unless there’s something in it for them.”
Some experts argue that keeping bats healthy and alive is indeed in our own best interest. Consider this: bats eat half their body weight — sometimes more than their entire body weight — in bugs every night. If you see bats flying around your backyard, you should be happy, the argument goes, because you won’t have to worry about mosquitos.
Some researchers claim the bats’ taste for insects is also a huge boon to agriculture. One study found that bats were worth billions of dollars a year in pest control services to U.S. farms alone.
“I’ve had students build giant cages in the middle of cornfields to keep bats out of certain areas. And we found that where you pulled bats out of the system or where bats couldn’t get to certain parts of the field, you saw an increase in damage [to the crop],” says Justin Boyles, an assistant professor in the zoology department at Southern Illinois University.
Boyles says other experiments show that bats have a positive effect on pecan crops and cotton production in the southern U.S.
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But not all researchers buy the idea that humans benefit so greatly from the creatures.“For the Canadian [agricultural] scene, that is just straight bullshit,” Fenton says. “I’m not even slightly convinced by these arguments about mosquitos or agriculturally important insects. People say it. But they say it more because everyone likes to hear it than because it’s true.”
“We have been taking bits of insects out of bat shit and identifying the insects using DNA barcoding. When you do that, you find that bats are eating many, many different kinds of insects. With the little brown bat, I think our list is over 800. And there are some insects that are pests, but most insects aren’t pests,” he says.
So while bats eat a lot of bugs, most of the time they’re not killing the ones we want them to kill, Fenton says. On top of that, there are so many insects flying around that bats can barely make a dent. And we shouldn’t thank bats for keeping mosquito populations low either, according to Fenton. Mosquitos are so small, it’s just not worth the bats’ while.
Both Willis and Boyles say, though, that even if conclusive evidence of bats’ direct usefulness to us doesn’t emerge, we should still care.
“It’s a problem in the natural world that we’ve created, and it’s a massive problem. So that’s one reason to care,” Willis says. “When you lose biodiversity, you lose resilience in your eco-system.”
Fenton questions the very idea of defining our relationship to nature according to how much humans benefit.
“Is the whole world anthropocentric, and if something isn’t doing good for us, do we have to therefore not worry about it?”
Video shot and edited by Matthew O'Mara.
CORRECTION: The article originally stated that Craig Willis was with the University of Manitoba. He is actually a professor at the University of Winnipeg.
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