Biologists count bats in abandoned Lincoln County ranch house

The four of them have the house surrounded.

They’re armed with red-beamed spotlights and handheld pitch counters, a pair of eyes on every exit.

At first, the Washington Department of Fish and Wildlife crew waits patiently in the weeds as the blue sky fades. A handful of coyotes howls in the distance. Squeaks start to pour from the rafters.

“It’s in the middle of nowhere, but it’s peaceful,” Dana Colley said while she waited.

A minute later, a lone bat pops out the back door, flying its herky-jerky flight in the gloom. Colley clicks her pitch counter and the night’s work has begun.

On a brisk June 15, WDFW counted a colony of bats in remote Lincoln County.

The counters drove out past green hills of wheat, down bumpy two-tracks to an abandoned ranch house with chipped white paint and red trim. They got in position before the sun set, then tallied the Yuma myotis bats as they flew out, one by one.

It may not sound exciting, counting bats in no man’s land, but counting animals helps biologists better understand the health of an ecosystem.

Michael Atamian, a WDFW district wildlife biologist, said his department monitors bat colonies for a few reasons.

For one, wildlife agencies throughout the country want to track the spread and effects of white-nose syndrome, a disease that has decimated bat populations in the eastern U.S. and can sometimes wipe out 90% of a colony. Biologists have detected the fungus in Washington, although it hasn’t been devastating colonies here the same way it has back east.

Checking for white-nose isn’t the only reason to keep an eye on bats. The animals are insectivores, which makes them good environmental indicators. If their numbers dip, it suggests something’s amiss lower down in the food chain.

“If these species are doing well, it’s an indicator of a healthier ecosystem,” Atamian said.

Bat counting may also remove some of the mystery surrounding the flying mammals. They’re relatively understudied.

“We don’t know what our bat population is,” WDFW Assistant District Wildlife Biologist Carrie Lowe said. “We don’t know where they go. There’s all these things we don’t know.”

Collecting data on a handful of colonies won’t solve every bat mystery, but it still provides wildlife agencies with data that could be valuable in the coming years and guide future management decisions.

Atamian called the June 15 count “very unsatisfying.” The WDFW crew only saw about 100 bats.

A few weeks earlier, at the first of the two annual counts, the crew saw 187.

“I have no idea what’s going on,” Atamian said.

Atamian and Lowe monitor five maternal colonies in Eastern Washington in spring and summer, when females are caring for their flightless pups. Four of those are stable or growing in population.

But the ranch house colony’s population has fallen dramatically in recent years and they don’t know why.

White-nose syndrome doesn’t seem like the culprit. Maybe the microclimate inside the house has become warmer or cooler as the building slowly falls apart. Maybe insect populations haven’t recovered from the 130,000-acre Whitney Fire in 2020, which burned near the house – although the colony was shrinking before then. Maybe the drought has taken a toll.

For now, they’ll record the data and hope to figure out what’s happening to these bats another day.

“More questions than answers,” Atamian said, “which is unfortunately more typical than not.”