Fri July 18, 2014
How To Listen For A Spotted Bat
Moses Coulee is a bat-lovers paradise. Washington is home to 15 species of these flying mammals and you can find 14 of them in this deep ravine about 45 minutes north of Ephrata.
And one of those species is the most rare type of bat in the state: the spotted bat.
There’s one thing especially cool about this bat: people can hear its echolocation. (Audio courtesy of Neal Hedges.)
“Listen real carefully and above the crickets you should hear another very insect-like call. Let’s see if you can hear this,” said Chuck Warner, arid lands program director with The Nature Conservancy in Washington.
Did you catch that clicking sound? That’s a spotted bat.
Warner has been organizing volunteers to listen for spotted bats for 14 years. The volunteers provide a census of the large area all at once.
“We’re hoping that we can use this information as a surrogate for how the bat species are doing in general in this area,” Warner said.
Bats are a keystone species. They eat insects. They help pollinate. They can even help reforestation after a wildfire. That’s why The Nature Conservancy wants to know how they are doing.
Neal Hedges started studying the bat population in this area in 1992. He helped the researchers who first discovered spotted bats in the Northwest.
“This [part of Moses Coulee] has the most spotted bats of any place in Washington that we found,” Hedges said.
Hedges was the first person in Washington to trap a spotted bat. Biologists here have only caught them twice.
“It’s a striking bat. It’s black and white, and it’s got really long ears that are kind of pinkish. It’s got one of the longest ears of any of the bats in Washington. It’s a beautiful bat,” Hedges said.
Spotted bats are also found roosting on high cliffs in Eastern Oregon and Idaho.
Hedges led two volunteers out to a spot close to where he caught the spotted bat.
“You know, once you guys learn this call, it’s going to drive you crazy at camp,” Hedges said.
Volunteer Stephanie Burgart laughed. “Didn’t think about that. The one time I forgot my earplugs,” she said.
Burgart said she can’t wait to hear the spotted bats flying around the coulee – even if the sound might make it harder to sleep.
The group decides on a good listening spot, and soon after, a large bat swoops down.
"There's another one," she points a bat as it flies over her head.
That make most people jump. Not Burgart.
“They’re one of the uncharismatic creatures that people just don’t give a lot of attention to. And so they’re a little less known, and I just think they’re super cute,” she said.
The spotted bats haven’t come out yet, but the sun is quickly setting, and the moon is rising. The spotted bats will soon leave their roosts on the high cliffs.
That’s when Burgart and her husband, Dennis, will start counting the bat’s echolocation clicks. They listen for clicking noises, which is how they know a bat is flying overhead. The sound is pretty distinctive once you know what you’re listening for.
"I counted 30," Stephanie Burgart said, as a bat flies near.
"I heard 34 down coulee," Dennis Burgart said.
All in all, Stephanie Burgart and her husband heard 15 bats flying overhead.
The Nature Conservancy’s Chuck Warner said this year's bat counts were slightly lower than normal. Most of the counters heard about 22 bats over one hour.
“By and large, I’m surprised that the count isn’t higher because it’s so still tonight – at least where we were. But the bugs were so loud you couldn’t hear anything else,” Warner said.
The Nature Conservancy is using tactics like weed management and controlled grazing to restore habitat in this part of Moses Coulee.
The conservation group is hoping that will attract more moths and insects. With more food, they hope, will come more bats.