Nothing stops a chat between birders faster than a flash of feathers in the sky.
Just a few steps into their stroll through Sax Zim Bog, three naturalists go hush at the sight of a Canada jay, a gray-and-white songbird with a fluffy coat of plumage to insulate it through harsh winters. It’s also called a camp robber for its inquisitiveness around picnics.
“I love Canada jays. They’ve been associated with humans probably forever,” said a delighted Sparky Stensaas. “They’re extremely intelligent corvids, but they also associate people with food.”
Stensaas founded Friends of Sax Zim Bog to protect this unique habitat about an hour north of Duluth, Minn., that attracts wildlife enthusiasts from around the world. In addition to drawing tourists, it’s also become a hub for scientists studying how climate change is affecting boreal species.
Peter Burke visits every February with the Rocky Mountain Birding club from Colorado.
“I come here for the owls. We’ll be looking out for the short-eared owls. Long-eared owls. [Northern] saw-whet owls. And if we’re really lucky, a boreal owl,” he said. “These are just little feather balls that can survive negative 30 degrees up here like it was nothing. Owls are awesome. And they look right back at you in the eye.”
Every winter, birders descend on the Arrowhead Region of Minnesota for a glimpse of owls, hawks and rare songbirds migrating from the north. Human visitors to Sax Zim Bog have to bundle up this time of year, but it’s a comparatively balmy getaway for birds who spend most of their time in Canada.
“This is the Arctic Riviera,” said Stensaas, and its avian resorts include a patch of wizened evergreens that lurch out of the squishy earth.
“Some of these 30-foot-tall trees may be 100 years old,” Stensaas said. “It kind of blows people’s minds when you say this is an old-growth forest because it just looks like a stunted, scraggly part of the taiga in northern Canada.”
What seems like an unassuming landscape in winter is teeming with activity for birders who know where to look. But some animals’ ways of life are threatened by the warming climate. Take the Canada jay, for example.
“They’re very vulnerable to climate change because they cache food in the winter, in preparation for the breeding season where they need more energy,” said Alexis Grinde of the Natural Resources Research Institute at the University of Minnesota.
“As the winters warm up, some of those things that they cache, like chunks of meat from a dead deer on the road, will rot,” she says, “So they won’t have as much food stored as they go into the breeding season.”
Grinde says climate change is starting to force a northward shift in some bird communities that will likely continue for decades.
“Hopefully, we can restore some of the habitats to maintain some of these climate refuges,” she said.
Listening in
Ornithologists are adept at spotting elusive birds in the wild, but they can’t catch everything. That’s why the Friends of Sax Zim Bog recently installed listening devices to capture bird calls around the clock and analyze them with the help of artificial intelligence.
Volunteer Rich Hoeg built several units of what he calls BirdNET-Pi, a rugged box with recording equipment that taps into an AI-powered database of birdsongs run by the Cornell Lab of Ornithology.
“I’m a retired techie, and I had always been intrigued with birds here in northern Minnesota,” Hoeg said. “When I was a kid, I lived next to a forest, and I was allowed to go traipsing around the forest by myself and be home by suppertime.”
In addition to Sax Zim Bog, Hoeg monitors listening devices in some wilderness areas and his own backyard in Duluth. He says bioacoustics have revealed a hidden world around him.
“Last fall, my BirdNET-Pi said, ‘You had sandhill cranes,’ and I go, ‘No way. This thing is totally messed up because I live in the boreal forest and there’s just no way a sandhill crane would be there.’ But I went and listened and I realized the device actually heard sandhill cranes migrating overhead that night. I’ve had the same thing happen with goldeneye ducks and common loons,” Hoeg said. “I’ve been really surprised.”
Sound from Sax Zim Bog is helping scientists study the migratory patterns of rare birds, including the Connecticut warbler. The recordings are also being used by the Owl Research Institute in Montana and the Natural Resources Research Institute at the University of Minnesota.
“We use them to understand habitat use of different species that are harder to detect, like boreal owls and great gray owls,” said Alexis Grinde. “It’s particularly important during the breeding season when they’re calling. Are they being successful? Are they having fledgling young? We can get answers to those questions just by listening to birds. It’s pretty cool.”
Carbon sponge
Deeper into the woods, a boardwalk carries hikers over a landscape rippled with three-foot hummocks. It looks like the whole bog has goosebumps. In summer, this is a lush grove of orchids, carnivorous plants, and thick mats of sphagnum moss.
“It’s sort of like a Lord of the Rings situation where you feel like you’re in a fairyland world,” Grinde said. “It’s cushy, and you can lay on it and then you go down and it’s just wet. There’s this amazing deep layer of it.”
If this wetland is a fantasy world, its sorcery is scrubbing climate pollution.
“Sphagnum moss is the unsung hero of carbon sequestration,” said Stensaas.
White settlers in the 19th and early 20th centuries, however, just saw a wasteland unsuitable for farming. They dug ditches to drain soggy swamps all over Minnesota and degraded the land’s ability to store carbon.
“So, we plug the ditches, the water comes back,” said Grinde, “and now it’s sort of the game of how do we restore the entire ecosystem function?”
A report from The Nature Conservancy says “rewetting” peatlands in Minnesota could soak up the equivalent of more than 6 million metric tons of carbon dioxide per year, equal to taking 1.48 million gas-powered cars off the road.
“It’s just one of our greatest opportunities for carbon storage,” said The Nature Conservancy’s Jim Manolis. “They cover about 3% of the Earth’s surface but store about 30% of the world’s carbon on the land.”
Magical swamp
On their way out of the woods, the naturalists spot hairy and downy woodpeckers, red-breasted nuthatches, wild turkeys, pine grosbeaks and an evening grosbeak, whose golden swish over the eyes makes it look like it’s furrowing a bleached unibrow.
“They’re a fun winter visitor that everybody loves to see,” Stensaas said. He hopes they will keep stopping by for future generations to enjoy.
As the climate changes, however, the cast of characters taking wing at Sax Zim Bog is going to change, too.
“For me, it’s been an existential crisis, buying up all this beautiful bog land, peatlands. What is this going to be like in 100 years or 200 years? I don’t know,” Stensaas said. “We’re purchasing and protecting habitat. Whatever it is, it’s going to be habitat.”
For now, at least, he said wildlife surveys have shown Sax Zim Bog is home to 4,000 species of plants and animals, including hundreds of rare birds.
“Most people think of this as a useless swamp. 4,000 species!” boasts Stensaas.
“It’s a magical, useless swamp,” Grinde says with a laugh.
This article was originally published on WBUR.org.
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