Wild critters in Wyoming’s backcountry aren’t fond of any noise made by humans, but chatty hikers and mountain bikers might bother them the most, researchers discovered.
Recordings of “larger groups, particularly vocal hikers and mountains bikers” were up to six-to-eight times more likely to send animals fleeing than recordings of other noises such as vehicle engines.
That’s according to a recently-published study conducted in Wyoming’s Bridger-Teton National Forest by biologists from the Forest Service’s Rocky Mountain Research Station.
“By ‘larger groups,’ we mean five-to-10 people, not huge crowds,” research biologist Dr. Kathy Zeller told Cowboy State Daily. Zeller is the study’s lead author.
Trail Cameras Set Off Recordings
The biologists’ method was unique but straightforward, she said.
Researchers started out by capturing recordings of outdoor recreation activities – such as hiking, mountain biking, people riding ATVs and the like.
Then they set up speakers and trail cameras in remote locations, mostly in the Greys River and Jackson ranger districts. When the cameras picked up an animal, that would trigger the recordings.
“We set them to play at the same decibel levels they were recorded at,” Zeller said.
The noises didn’t suddenly blast at full volume right away. The goal wasn’t to test animals’ startle reactions, she said.
Instead, they started off faintly, gradually grew louder, peaked and then started to fade.
That realistically mimicked humans or their machines approaching the spot, reaching it, and then moving away on down the trails, Zeller said.
Black Bears, Elk The Most Scared
The study was conducted from June until early October in 2022 and 2023, and the results were published this June in a scientific journal.
Some of the results were interesting, and even surprising, Zeller said.
For example, elk and black bears were the most skittish about the recordings, while mountain lions seemed to care the least.
Mule deer also tended to run away but didn’t seem quite as alarmed as the elk were.
In one video Zeller shared with Cowboy State Daily, a black bear is shown strolling along. But it turns and barrels off into thick cover almost immediately after a recording of human voices starts rolling.
By contrast, a photo of a mountain lion shows it casually walking away, looking perhaps mildly annoyed.
As for grizzlies, the longstanding advice from backcountry experts is that hikers should talk and make noise to avoid running into a bear by surprise.
Zeller said the study hasn’t included grizzlies so far. Only one came around the study sites, and it wasn’t when the recordings were rolling.
But the group is continuing research and hopes to capture some footage of grizzlies’ reactions.
Why Are Elk And Black Bears So Scared?
Elk and black bears being the most skittish might seem odd – given that those species frequently set up shop close to human settlements.
Black bears are frequently seen near Sheridan, and sometimes even in town. The summer of 2023 saw a rash of run-ins with bears there.
And for several months of the year, elk take over the town of Estes Park, Colorado. In separate incidents this spring, two children were stomped and injured by elk there.
Zeller pointed out that the study areas were remote. The elk and black bears there weren’t used to human presence, even if others of their kind have adapted to being around people in places such as Estes Park.
Beyond that, it remains unclear while some species were apparently more skittish than others about human noises.
One hallmark of a good study is that it generates as many, if not more, questions than answers, Zeller said.
“We have 1,000 questions,” she said.
Other Factors To Consider
Research is continuing this summer, she added. Distance is being added in as a factor.
Whereas the speakers were set up to produce noise right next to trails during the previous studies, researchers want to look into how big of a “buffer zone” there might be around people traipsing through the woods, she said.
To determine that, the current study is focusing on the effects of noise on wildlife from greater distances.
Thermal imaging video might also help determine just how stressed animals are when they hear humans, Zeller added. Greater stress might cause animals’ body temperatures to spike, and thermal imaging could document that.
However, the amount of gadgetry researchers can use is limited by funding, she said.
Could This Affect Policy?
Zeller said the research is important and timely because more people are going into the backcountry than ever before.
During the 2020 Covid lockdowns, people took the outdoors as an escape from the restrictions, and that trend has continued ever since.
Outdoor recreation has become an $860 billion-a-year industry, so there’s no end in sight.
Bearing that in mind, knowing how people’s speech and other human noises might bother wildlife is important, Zeller said.
“We designed the study to be useful to (land and wildlife) managers,” she said.
Since the study was published, several wildlife and public lands agencies have reached out to Zeller and her team, and she expects that interest to continue.
The results of the study, and further research, could factor into land use and recreation policy.
For example, the design of recreational trail systems moving forward might have to take into consideration the effects of people noisily reveling in the outdoors, she said.
Mark Heinz can be reached at mark@cowboystatedaily.com.
