Taking deliberate steps along the rocky bank, Monica Blanchard waded into the Stillaguamish, a roiling river that snakes through the lush conifer forests of northern Washington. It was a rare cloudless October day, and golden maple leaves rained down, flapping in the breeze like butterflies before joining their withered brethren on the riverbank. Blanchard, a fish biologist for the Washington Department of Fish and Wildlife, held two long white sticks in her hands — electrofishing wands designed to stun fish. The wands were connected to a backpack outfitted with knobs and switches to control the small electric current that runs through them. “This is my Ghostbuster backpack,” Blanchard joked. As the gray-green river gurgled around her ankles, she dipped the wands into the water and sent out tiny pulses meant to coax lamprey out from the sediment where they’d buried themselves. Sure enough, a larval lamprey wriggled out of the mud.
Known for having circular sucker mouths ringed with tiny teeth, adult Pacific lamprey resemble miniature versions of the sandworms from Dune. In their larval stage, they’re eyeless filter feeders. But once they mature, they become a fatty, calorically dense meal for predators like otters and sea lions; biologists joke that lamprey are little hot dogs in the water.
Lamprey have an ancient lineage — scientists believe they first emerged 400 million years ago. Though once abundant throughout the Northwest, their descendants are now under threat. In some regions, lamprey numbers have fallen by over 90%. Blanchard is here today to collect some much-needed data on the ancient fish that could help prevent their disappearance.
“They’re one of the world’s oldest fish,” Blanchard said. “And we know almost nothing about them.”
TRIBES ALONG the Columbia River, including the Confederated Tribes and Bands of the Yakama Nation, the Confederated Tribes of the Umatilla Reservation and the Nez Perce Tribe, have warned of lamprey’s decline for decades. The fish are what Native people call a first food: They were a source of sustenance during frigid Northwest winters, and they appear in foundational tales, origin stories and ceremonies, so that preserving lamprey is also a way to preserve a tribe’s cultural identity. The fish’s decline is largely due to settler colonizers, who built dams and culled lamprey to make room for salmon. Other factors, including climate change and habitat loss, have pushed Pacific lamprey to local extinction in parts of the Northwest, and yet they’re often an afterthought in conservation plans.
Scientists agree that documenting lamprey is the first step toward ensuring their survival. For the last seven years, Kellie Carim, an aquatic research biologist for the United States Forest Service, has led a major lamprey-tracking project. More than 100 scientists and volunteers have hiked creek sides and riverbanks throughout Idaho, Washington and Oregon, collecting data on where lamprey dwell. “Once we have that understanding, we can then start to understand and monitor for changes in that presence and distribution,” Carim said.
Scientists like Blanchard often use electrofishing to study lamprey. The equipment is cumbersome, though it’s helpful to have when researchers need to see the fish. Still, scientists like Blanchard also use another method to survey water and soil for bits of lamprey DNA — a technique called environmental DNA, or eDNA. After Blanchard electrofished, she placed a small plastic cup underwater. The bottom of the cup held a circular paper filter, and Blanchard will send it to Missoula for Carim to examine.
So far, Carim has analyzed more than 1,000 eDNA samples throughout the Pacific Northwest, as part of the eDNA Basin-Wide Lamprey Inventory and Monitoring Project. Scientists with the Pacific Lamprey Conservation Initiative, a coalition of more than 50 tribes, agencies and organizations, then combined that data with estimates of the fish’s historic range to assess lamprey’s conservation status. They estimate that lamprey have been blocked from or not found in more than 75% of their historic range in most of Washington, Oregon and Idaho, as well as in many parts of California. The data suggests that lamprey are at risk of local extinction in waterways across Puget Sound, since they have only been located at less than 25% of the streams they once occupied.
“I see it as a call to action,” Blanchard said. With better data, scientists can focus their efforts on where lamprey are most imperiled, and habitat managers in those watersheds can begin taking action to conserve them.
“They’re one of the world’s oldest fish. And we know almost nothing about them.”
Often, habitat managers don’t even know whether lamprey are in a waterway before restoration projects begin. “Everyone is salmon-centric,” said Rebecca Mahan, a habitat biologist for Clallam County. While lamprey and salmon face similar threats — mainly dams that block their access to upstream habitat — most habitat restoration and barrier removal efforts in the Northwest have focused on preserving salmonids. In some cases, those efforts can hinder lamprey. For example, the Washington Department of Transportation has replaced more than 100 culverts to help salmon swim under bridges and roadways. But lamprey are weaker swimmers than salmon and sometimes find the fast-flowing water inside culverts difficult to navigate. Fish ladders, too, are not built for them; lamprey find sharp corners and vertical sides nearly impossible to sucker onto.
Yet experts believe that lamprey will rebound, given the opportunity. “They can be easy to reintroduce if the habitat is good enough,” said Justin Stapleton, a project biologist for the Lower Elwha Klallam Tribe who studies lamprey. Throughout the Northwest, habitat restoration and reintroduction projects have successfully returned lamprey to regions from which they’d vanished. In 2013, at Bonneville Dam, 40 miles east of Portland, river managers introduced passage structures whose slow-moving water, smooth metal surfaces and angled ramps were specifically designed for lamprey — and biologists saw record numbers pass through the dam in 2023.
Back near the Stillaguamish River, Blanchard scrambled down a steep bank to the edge of a murky creek. Here, the water flowed gently over a muddy bed, and piles of leaves rotted in the water. It was perfect larval lamprey habitat, she said: soft, silty sediment, lots of decay. Lamprey eDNA had been found upriver of these locations, but she hadn’t yet found lamprey in the creek. She donned her electrofishing gear and got to work.
Natalia Mesa is an editorial fellow for High Country News based in Seattle, Washington, reporting on science, and environmental and social justice. Email her at natalia.mesa@hcn.org or submit a letter to the editor. See our letters to the editor policy.
This article appeared in the March 2024 print edition of the magazine with the headline “Saving the Pacific lamprey.”
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