The insect-gobbling critters can eat their own weight in bugs each night, including farm pests
Bats aren’t pretty and their reputation isn’t either.
But the insect-gobbling critters are friends of farmers — and they need help from producers, says the co-ordinator of the Alberta Community Bat Program.
“In Canada, all of our bats are eating bugs — insects and spiders,” said biologist Cory Olson. “Their diets are fairly diverse, but they are only eating bugs.”
The Wildlife Conservation Society of Canada, which runs the program, says bats will eat their weight in insects each night, with moths and mosquitoes being top menu choices, but also flies, beetles and caterpillar larvae.
But they’re also under threat, Olson said in a recent presentation put on by the Prairie Conservation Action Plan.
There are nine species of bats in Alberta. The Little Brown Myotis (a.k.a. the Little Brown Bat) and the Northern Myotis are listed as endangered because these species are suffering the devastating effects of a fungus called white-nose syndrome. The status of some other species are unknown and only the Big Brown Bat and the Long Eared Myotis are not conservation concerns.
“This is a little bit alarming considering how important bats are for biodiversity,” said Olson.
White-nose syndrome, a fungus introduced to New York state about 2008, has expanded across Canada and the U.S. It causes bats to more frequently wake during hibernation, so they deplete their fat stores and starve before spring arrives.
“It’s not in Alberta or Saskatchewan… but it is coming pretty close,” said Olson, adding it has been found in Manitoba.
“There’s not a whole lot we can do to stop the spread of white-nose syndrome. What we are focusing on is building resiliency in the bat population and that is the focus of our program in Alberta and the objective of other bat conservation programs.”
Another big issue is wind turbines.
It’s estimated each one kills 11 bats per year, particularly during the fall when species such as the Silver Haired and Eastern Red Bats are migrating. Given there are more than 1,000 turbines on the Prairies, the numbers add up fast.
“Potentially over 10,000 bats per year are killed by turbines in Alberta and Saskatchewan alone,” said Olson. “This rate of fatalities is believed to be unsustainable.”
Finding a place to live isn’t getting easier, either.
“Habitat loss is not unique to bats. It is affecting lots of Prairie species,” he said.
It doesn’t help that bats, while long lived, aren’t prolific breeders and that they have a rather fussy way of drinking, skimming low over a body of water and gulping.
“They are not landing to drink, so they need access to open water, free of obstructions like duckweed. It needs to be still,” said Olson.
They also need a place to roost, whether that’s a tree, under a bridge, or in a building. Olson recommends not evacuating bats from their homes when pups are in the roost.
“Pups can’t leave without their mother,” he said. “If the mother is excluded, the pups will die and decompose in the building, creating more problems for its owners.”
The best thing to do is just wait until they leave in October or November, and then do repairs to keep them out in future.
Yards are full of potential hazards for bats. They can crawl inside chimneys or chutes and become trapped. Rain barrels and water troughs are also major threats, house cats kill an unknown number, and they can even get caught on barbed wire.
There are several guides on being bat friendly available at www.albertabats.ca, including making a yard more bat friendly, creating a bat home, or removing them from a building.
Olson is currently working on a project to investigate bats as a control of pests in agricultural environments and is looking for farmers to take a survey on their perception of bats (here’s a link to the survey).