Bats enjoy hanging out on Wyoming bridges and in mountain caves, creep some people out and are good for the environment.
They’re also fighting for a future in the Cowboy State.
Except for being creepy, those are some of the findings University of Wyoming Assistant Professor Riley Bernard and graduate and undergraduate students in her research lab have uncovered pursuing the winged creatures of the night.
Bernard, an applied wildlife ecologist in the university’s Department of Zoology and Physiology, said it’s concerning if bats are having trouble thriving in Wyoming.
“Bats are wonderful they are good for humans because they eat the bugs that bother us, they eat the pests of our ag lands, and they are inherently fun to see at night,” Bernard said. “I always say, ‘Look up at night.’ It’s cool to see them out there because they are doing really cool stuff.”
She also said they get a bat rap with their association to vampires, Halloween and a reputation for general spookiness.
“They are not as scary as we think,” Bernard said. “They don’t want to come at you, they don’t want to get in your hair, they want to do their own thing.”
Research projects from her lab examining at the impact of white-nose syndrome on Wyoming species, bat habitats, and the future of the threatened Townsend’s big-eared bat are part of ongoing collaborations with other state and federal entities to identify needs and protect the flying mammals.
Bernard said white-nose syndrome that was first identified in the U.S. in 2006 in the East, and estimates are that 6 million bats in the nation have died from the disease. It was first revealed in this region through research in the Black Hills of South Dakota in 2017.
Bats Declining
Research data beginning in 2017 through 2022 show a decline in several species of bats.
Of 18 species of bats originally identified in Wyoming, 11 are susceptible to the fungus-caused disease. All 11 species hibernate, while those not susceptible migrate. Hibernation is hard on bats because their body temperature lowers, Bernard said.
“When they are entering hibernation mid-September to around April the fungus just has an all- you-can-eat buffet,” she said. “The bats are programmed to eat enough food in August and September to have enough fat stores to survive through the winter, just like a bear.”
That’s when the fungus wakes up.
The bat’s immune system then kicks in and “eats away at skin membrane” removing tissue from their wings.
Bernard said her lab is involved in a collaboration with Wyoming Game and Fish Department, the U.S. National Park Service and a couple of other entities in a vaccine trial at a few sites around the country and in Canada.
In Wyoming, the effort is mainly at Fort Laramie.
“There is a huge bat box of 7,000 little brown bats,” she said. “Results are a few years in, and we are seeing some promising results where the bats are surviving or the fungus in these sites is decreasing.”
Another effort by a conservation group is trying to vaccinate the northern long-eared bat population near Devils Tower. They have captured and vaccinated only a dozen, and results are yet unknown, Bernard said.
Vaccinating the bats is very labor intensive because researchers use plastic disposable droppers to drop the vaccine into the mouths of captured bats.
Bernard said researchers hope eventually to possibly put the vaccine into a “goo” form on a wall “that a bat can walk over, like in a big maternity colony, and then they can groom it off each other.”
A photo of Townsend’s big-eared bats in a Wyoming cave. (Courtesy Riley Bernard) 
University of Wyoming Assistant Professor Riley Bernard shares information about Wyoming’s bat population to a gathering at the Werner Wildlife Museum in Casper. (Dale Killingbeck, Cowboy State Daily) 
University of Wyoming Assistant Professor Riley Bernard shows 18 of the 20 bat species now in Wyoming. (Dale Killingbeck, Cowboy State Daily) 
University of Wyoming Assistant Professor Riley Bernard shows the population decline in Wyoming bats between 2017 and 2022. (Dale Killingbeck, Cowboy State Daily) 
Researcher Nick Kovacks tries to track a bat in 2021 at Guernsey. (Courtesy Riley Bernard) 
Magnification of one of the bugs attaching themselves to bats in Wyoming. (Dale Killingbeck, Cowboy State Daily) 
University of Wyoming Assistant Professor Riley Bernard with some of her lab team netting bats under bridges. (Dale Killingbeck, Cowboy State Daily) 
Bats on display at the Werner Wildlife Museum presentation by University of Wyoming Assistant Professor Riley Bernard. (Dale Killingbeck, Cowboy State Daily)
Guernsey Bats
Still another effort has been at Camp Guernsey Joint Training Center, where a natural resources manager there wanted to determine if three species of bats targeted for conservation concern and battling white-nose syndrome were on the base.
Her lab research team used radio telemetry devices as well as acoustic recording devices to track and identify bat species at the camp.
“We were able to track bats to a hole at the site,” she said. “We also tracked a little brown bat 2 miles from where they captured her to a male bathroom on base.”
She said the team found at that site the big brown bats they used to capture in larger numbers have declined and myotis species — bats with mouse ears — that are subject to the white-nose fungus are not being captured at all.
However, their acoustic recording device did record a “decent amount” of brown bats and long-legged bats.
In addition to the white-nose research, Bernard said students in her lab have looked at bat habitat. One team from her lab surveyed 500 Wyoming Department of Transportation bridges around the state and found bats at 75 percent of them.
“They had about 13 sites with active roosts, so bats are there during the day and you have some that are just adults and some maternity roosts,” she said.
A study of bat guano from the sites determined that nine species of bats were using bridges as habitats and that little brown bats, a species petitioned for an endangered listing, was at every bridge that had bats.
“So, this information is highly useful to WYDOT because they need to minimize any action that could likely deal with losing those roosts,” Bernard said.
Research also revealed that bats were three times more likely to be at a bridge over a body of flowing water and through the guano study, researchers uncovered that a new species of bat, cave myotis, is in the state.
“So, we will be digging into that,” Bernard said. Another surprise came when the Wyoming Natural Diversity Data Base found a 20th species of bat in the state “which is pretty awesome given how far north we are and how cold our winters can be.”
New Behaviors
A third research effort has targeted Townsend’s big-eared bats, a species considered for the “greatest conservation” need.
Bernard said the bats are subject to climate change, and that can lead to roost abandonment. Her team sought data to improve management and conservation of the species.
Her team netted, trapped and used long-term acoustic devices to monitor caves known to house the bats. One of the things they learned is that gates placed on caves to protect the bats from humans and still allow bats to fly in and out created some navigational problems for some bats that hit the gates.
“Bat wings are very delicate and they can break fingers or forms, so we are trying to figure out how these bats are navigating these sites to see if managers need to change cave gates or minimize that as an outcome,” Bernard said.
Her team also discovered three new roosts sites in cracks on mountain climbing sites. Townsend’s bats seek news sites when they are angry or disturbed.
Bernard said the species has never been known to use mountain cracks before.
“So, we are documenting some new behaviors,” she said.
Because the roosts are on U.S. Forest Service property, Bernard said they have informed the agency so they can protect the sites.
In addition to the lab research projects, Bernard said she collaborated with a colleague who participated in rafting the Green and Colorado rivers in 2019 as part of the 150th year celebration of John Wesley Powell’s exploration of the rivers in 1869. Her colleague took bat acoustic recording equipment along for the trip and asked her to help analyze it.
Bioindicators
Bernard said scientists believe bats could be good bioindicators of how river and stream ecosystems are performing, whether the environment is clean or polluted.
Bernard said her analysis found 58,000 bat calls and 19 different species along rivers that varied among the different sections from the Wyoming basin, to middle Rocky Mountains, to the canyon lands.
One finding was bat activity was much more present in fast water than reservoir or slow-moving waters. She thinks it could be related to insect activity or bats are using those areas as channeling corridors.
Bernard said data from trip can be used in the future for comparison to see if there is decline in any of the species.
One way Wyoming residents can help the bat population is to install bat houses on their properties. September and October is a good time to erect them because ground isn’t frozen, which in several areas of the state is likely when bats start to emerge in the spring.
Bernard said the houses should be multi-chambered, about 13 feet high, be placed in a location for at least six hours of sun and be painted dark colors.
“That way you have bats around to keep mosquitoes down and pests out of your garden,” she said.
In response to a question from a younger person in her audience about whether people are allowed to eat bats, Bernard advised against it. She said one reason is the diseases they can carry. She acknowledged certain bats are eaten in some cultures.
“I’ve been offered bat before in Cambodia,” she said. “I said, ‘I’m good, thanks.’”
Dale Killingbeck can be reached at dale@cowboystatedaily.com.
