It's about 25 degrees on a clear Saturday morning when Gregg Treinish — executive director of Adventurers and Scientists for Conservation, a nonprofit that puts volunteers to work gathering data for scientists around the world — gathers a small group of outdoor adventurers around him near the Duckabush River in the Olympic National Forest in Washington state.
The mission for this group: help biologists figure out whether there are any martens left in the Olympic National Forest. Volunteers will set up motion-activated cameras in some of the forest's snowiest, most remote territory.
The citizen scientists fill their packs with a strange assortment of gear, including chicken wire, hammers, folding saws and — wait for it — human-head-sized chunks of beaver carcass.
"I don't mind carrying dead things, but maybe I'll move my lunch," says Sonia Wolfman, a lawyer from Olympia, Wash., as she stuffs a black garbage bag full of beaver guts into her pack.
The beaver, which was provided by the Forest Service, will be used as bait to lure the martens in front of the remote cameras the volunteers plan to set up throughout the forest.
But in the Olympics anyway, catching a marten, a member of the weasel family, on camera is a rare occurrence.
"For the past 25 years, we've had three verifiable sightings," says Betsy Howell, a biologist with the Forest Service who helped organize this project. "Two were photographs and one was an animal caught in a trap."
Although martens are doing OK in parts of the mountain West, their numbers appear to have plummeted in recent decades in the coastal ranges of Oregon and Washington.
Until scientists know that for sure, these animals can't be recommended for protection under the Endangered Species Act. That's where these volunteers come in.
Treinish leads the group into the woods at a brisk pace. He's a tightly muscled guy with mountain-man hair and an easy smile. When he hikes, his eyes remain glued to the forest floor, scanning the snow. He picks out the tracks of mountain lion, elk, coyote, bobcat and a host of rodents along the trail, and points them out to the group. But no sign of martens.
After more than four miles of hiking up steep switchbacks and past sparkling icy rock faces, we get to a spot that looks like a place martens might hang out. To the untrained eye, it looks like every other snowy section of forest we've hiked through, but not to Treinish.
"It's a nice flat area here," he explains, pointing at a dip in the landscape where a young cedar and fir tree stand about 13 feet apart. "I kind of like how it funnels everything into there, so we'll go with that spot."
The group unloads its gear and starts setting up the station.
Jenna Walenga, a barista from Seattle, snaps on a pair of rubber gloves and prepares to reach into the bloody garbage bag. A few years ago, she hiked Mount Kilimanjaro. Today her job is to attach a hunk of dead beaver to one of these trees.
"I'm actually a vegetarian," she says, as she holds the carcass against the tree so another volunteer can nail it down beneath a layer of chicken wire.
On the opposite tree, the team sets up the motion-activated camera and aims it at the beaver carcass.
The chances of getting footage of martens in the Olympic National Forest are slim. Much of the old-growth forests the martens rely on in the coastal range has been cut down, and biologists worry that climate change will shrink the remaining cold alpine habitat.
No one knows how many martens might still live in the national forest, but Howell says they'd probably never be able to find out without the help of volunteers like these.
"We can do so much more together than we can do separately," Howell says. "The partnership is a great way to get work done that otherwise we just don't have funding or staff for anymore."
The volunteers will set up 11 other stations like this one throughout the forest. Then they'll come back in smaller groups to check the cameras every month or so to see whether any martens showed up to have their pictures taken.
It's still legal to trap martens in Washington and Oregon. But here in Olympic National Forest, there may not be any left to catch — on camera, or otherwise.