Alaska’s Bat Population Probed

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It’s 1 a.m., and the dim glow of the sun just peaks over the horizon at Potter Marsh, a popular bird watching spot in South Anchorage. Veronica Padula and Keegan Crowley, both students at the University of Alaska, meander down a zig-zagging boardwalk and scan the horizon. The two researchers aren’t trying to spot cranes or herons. They’re looking for bats.

A map of the Little Brown Bat's known range in Alaska. The Little Brown Bat is the most common bat in the state (Alaska Department of Fish and Game).
A map of the Little Brown Bat’s known range in Alaska. The Little Brown Bat is the most common bat in the state (Alaska Department of Fish and Game).

“It’s like a treasure hunt,” Padula says with a chuckle.  “Last night we were really stoked when we finally found a bat.”

Padula and Crowley have been patrolling Potter Marsh for the past week trying to determine where bats feed, so they can come back later with nets to catch the animal for study. To assist in the hunt, Crowley uses a small ultrasonic recorder that measures the frequency of bat calls.

“When they’re feeding you’ll see a bunch of small, shorter calls because they’re trying to be really accurate to find the tiny insects,” Crowley explains, before being interrupted by the shrill chirp of a bat weaving through a meadow a few feet in front of him.

After consulting the recorder, Crowley and Padula determine the bat is feeding. Next week they plan to set up nets in the area to catch the critter.

The research at Potter Mash is part of a broader effort to try and understand bats in Alaska. While the mammal occupies a huge swath of land between the Brooks Range in the Arctic and Alaska’s southernmost boarder with Canada, they remain mysterious.  “What we don’t know about bats far outweighs what we do know,” says David Tessler, a biologist with the Alaska Department of Fish and Game.

For example, scientists don’t know whether the mammal spend their winters in Alaska or migrate, if they nest in caves, trees, or man-made structures, or how long they’ve occupied the far north.  And while there are six known species of bats in Alaska—most living in south-east—there could be more.

“There aren’t many times in wildlife biology…where you can embark on something entirely unknown,” Tessler says, “and we know almost nothing about bats here, so that’s exciting.”

But the lack of information could make it hard to protect Alaska’s bats from the fungal disease White Nose Syndrome. First discovered in New York in 2006, the disease covers bats in white splotches of fungus, and causes them to come out of hibernation in the winter and act abnormally.

Little Brown Bat affected by White Nose Syndrome  (U.S. Fish and Wildlife Service)
Little Brown Bat affected by White Nose Syndrome (U.S. Fish and Wildlife Service)

During the early days of the disease there were reports of swarms of bats hovering over interstates during wintertime daylight hours—a time period bats typically spend hibernating. Some caves were found overflowing with tens of thousands of dead bats. And the animal displayed erratic behavior, such as flying into people and objects. To date, the disease has killed more than six million bats in twenty five states and five Canadian provinces.

“It has been called the greatest wildlife disease of our lifetimes and it’s impacting the mammal in a major way,” says Jeremy Coleman, national White Nose Syndrome coordinator with the U.S. Fish and Wildlife Service.  “We are seeing demise akin to the passenger pigeon and the American bison.”

While White Nose Syndrome hasn’t made it to Alaska yet, that doesn’t mean the state’s safe. Researchers say the disease is traveling about 200 miles per year, and the fungus could potentially spread throughout all of North America. If it finds its way to the last frontier, White Nose Syndrome could wreak havoc on the state’s ecosystem. One obvious impact would be an increase in the number of small insects.“It’s estimated that one bat can eat as many as 5,000 mosquitoes a night,” Tessler says, “so they’re actually very, very useful in controlling pests.”

With such a shortage of information on Alaska’s bats, though, it’s hard to know if or when White Nose Syndrome will arrive. Which is why Veronica Padula and Keegan Crowley are romping through Potter Marsh in the early morning hours, trying to find and catch the nocturnal mammals.

“It helps us get to know better where they’re roosting and if they’re staying here over winter or migrating,” Padula says. “A bat in the hand can tell us many, many things.”

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