Research to help conservation and recreation planning efforts
By Bob Berwyn
FRISCO — A multi-year Forest Service study aimed at better understanding how lynx react to human recreational activities was expanded to new areas in Colorado this year, including Loveland Pass, Leadville and Telluride.
Previous efforts have focused on the Vail Pass Winter Recreation Area, where scientists captured lynx and fitted them with collars to transmit GPS data. At the same time, the Forest Service researchers asked skiers and snowmobilers to take GPS transmitters along on their excursions.
A thorough analysis of the data will help land managers make science-based decisions about how to allocate resources as they balance the demand for recreation with a mandate to protect habitat for rare animals like lynx, protected under the Endangered Species Act.
In some cases, for example, it’s becoming clear that lynx apparently can co-exist with recreation in an area like Vail Pass, with some of the GPS data showing that the cats just hunker down, hiding in thick cover when snowmobiles or skiers cruise past.
On a broad scale … they use very different areas, they like high density cover. You can’t snowmobile in it , it’s not that fun to ski and crash through … Lynx and snowmobilers can co-exist, maybe there’s less of an issue than people think,” Squires said. “I think lynx can take that sort of contact, sometimes they’ll just sit there and watch you. When you drive a snowmobile past a lynx, they don’t even move, they stay in their cover, and they go on being lynx.”
“Trying to study something like lynx, a rare carnivore, and the relationship between lynx and recreation is difficult,” said Forest Service biologist John Squires, based at the Forest Service’s Rocky Mountain Research Station in Missoula.
Squires, who has been studying lynx since 1998, said the idea is not just to have an anecdotal story, but to quantify how humans move through the environment with the same rigor used for tracking lynx.
“GPS allows us to do that,” he said, adding that the lynx and recreation studies have also been done in the San Juans, around Molas Pass. Expanding the research to Loveland Pass and Leadville will help develop a broad data set that tells more the story, he said.
“We’re just trying to understand the relationship between lynx habitat use and recreation …and the broadest depiction of how people move through the landscape. We also have an objective in our studies to see how lynx use ski areas, but that’s difficult,” he said. “The main challenge is finding enough animals juxtaposed to ski areas and trapping them,”
“We want to get our sample size high enough so that it’s representative of the population … They have large home ranges, big areas have just a few individuals … it’s now getting more difficult. We’ve done the easy areas … there are lots of places where lynx are that there’s very little recreation,” he said, explaining the choice of Loveland Pass as a new study site.
The researchers start by tracking lynx in the snow. After finding a well-used lynx trail, they set up box traps, made of PVC piping and chicken wire, baited with deer meat. Once the lynx are collared, they’re released back to the wild. Once the winter is over, the biologists retrieve the collars and start to evaluate the information.
At the same time, skiers and other users of the area are asked to carry a GPS unit on their backcountry treks.
Squires said the public has been very receptive of the Forest Service efforts.
“This study depends on citizen science. We’ve been so well received by all users. That’s been a huge success,” he said.
So far this winter, the scientists haven’t been able to capture a lynx around Loveland Pass. Based on other data, primarily compiled from earlier Colorado Division of Wildlife studies, the area may be part of an important north-south movement corridor, used by the wild cats to disperse from core habitat areas in the San Juans to colonize new territories.
State research shows a clear pattern of lynx crossing I-70 just east of the Eisenhower Tunnel, around Bakerville. There have also been reported lynx sightings around Keystone, Montezuma and Arapahoe Basin.
“There’s a long history of lynx occupation in that area,” he said.
Even though they haven’t been able to capture lynx in the area, the data from skiers is valuable in itself, helping to show which areas are being used for recreation on a consistent basis.
Similar efforts around Leadville are also under way, but Squires said the lynx aren’t cooperating.
“They’re walking past our traps every night. Part of the problem is this mild winter … they’re not as enticed by bait,” he said.
The studies are focused on winter because that’s the most constraining time for lynx, Squires said, explaining that the cats often starve to death in late winter and early spring.
“That’s when people were most concerned. This is a winter issue,” he said.