“Lampreys are delightfully bizarre fish — and vastly underappreciated for the role they play … in ecosystems.” — Center for Biological Diversity
By Lee Anna Sherman
Ask a random sample of Oregonians what they know about Pacific lamprey, and you’ll likely get one of the following responses:
“Um, not much. Aren’t they some kind of eel?”
“Ooo, yuck! They’re parasites, right?”
“Oh, yeah, I saw those on River Monsters.”
These answers ordinarily come with a wrinkled nose or a shudder of disgust. To most people, lampreys seem icky or scary or both. It doesn’t help their image that one of the world’s 40 lamprey species, the sea lamprey (Petromyzon marinus), is invading and imperiling the Great Lakes. Nor does it help that Animal Planet’s “extreme angler” Jeremy Wade recently did an episode of River Monsters titled “Vampires of the Deep.” During his hunt for lampreys in Oregon’s thunderous Willamette Falls, he cranked up the drama with a script worthy of a low-budget horror movie. Amidst the churning, roaring waters, he shouted about the “slimy, serpent-like vampires!” and “primordial bloodsuckers!” he was soon to bag.
Wade did get one thing right when he said, “Lampreys are survivors from the depths of time.” For eons, Pacific lampreys (Lampetra tridentata) by the millions have scaled Willamette Falls — a 40-foot-high natural waterfall between Oregon City and West Linn — to reach their spawning grounds in the Santiam, the Pudding, the Long Tom, the Marys and the other tributaries of the Willamette River. A black-and-white photo taken at the falls in 1913 shows a Medusa-like tangle of lampreys — thousands of shiny, serpentine creatures packed together on a rocky ledge — as they thrust upward against the torrent.
For millennia, Northwest tribes harvested lampreys from those very same watery ledges, plucking them from the rocks by hand. Then, early in the last century, pioneer families began dining on lamprey, and European-American fishermen joined in the harvest, collecting the three-foot-long jawless fish at Willamette Falls by the boatload for processing into fishmeal, vitamin oil and livestock feed. The yearly catch hit a high of 185 tons — a half-million lampreys — in the 1940s, according to a 1999 report of the Columbia Basin Fish and Wildlife Authority.
Once upon a time, before European settlement, the tribes had bountiful places to catch Pacific lamprey, a sacred staple in native diets. Back then, lamprey dwelled throughout the Columbia River Basin. But in a few short decades, the ancient fish have disappeared across most of the watershed. Today, the Willamette River is the last stronghold of an animal that biologists describe as an evolutionary marvel. Having survived at least four of Earth’s major extinction events, the Pacific lamprey is collapsing, defeated by dams, pollution, habitat loss, dwindling host fish and factors yet unknown to scientists.
“It’s death by a thousand cuts,” says Oregon State University fisheries biologist Carl Schreck.
The English term “lamprey” derives from the Medieval Latin word lampreda. Translation: “stone licker.” The weird name comes from the fishes’ curious ability to climb vertical rock faces with their mouths — suck on, wriggle up, suck on, wriggle up. The amazing functions of their suction-cup mouth, which scientists call an “oral disc,” also include latching on to other fish. Certain websites have dubbed adult lamprey “aquatic hitchhikers” for riding along with salmon, cod, flounder and even whales while feeding on their body fluids.
Their mouths play a key role, too, in building spawning nests (“redds”). By sucking onto large river rocks, lampreys can scoot the stones along the riverbed and arrange them in a circle on the gravelly substrate. The rocks form a protective barrier against currents that might wash away the eggs — as many as 100,000 per female fish.
One morning in May, two Oregon State fisheries biologists wearing Polarized sunglasses quickly spot at least a dozen such redds in the Luckiamute River, a Willamette River tributary northwest of Corvallis. Velcroed into their Simms “Pro” stocking-foot waders, researchers Luke Schultz and Mariah Mayfield are standing in an alder-shaded pool. Sunlight flickers through the leaves and glints off the riffles. Trees leaning lazily over the water catch the reflection on the underside of their trunks.
“See that speckled dace?” Schultz says, pointing down at the pebbled riverbed. “It’s hovering right inside a redd.” The finger-sized fish rests over a rounded depression the size of a pizza. Schultz points out another depression and another, noting the large stones rimming each hollow. As the female lamprey deposits her eggs by fanning her body across the nest, she grips a rock with her mouth for stability. “A month ago, we saw a lot of adults here,” Mayfield reports. “We saw a lot of carcasses, too.” Like salmon, lampreys die soon after egg laying. Their bodies nourish other riverine species.
Schultz and Mayfield, who work in Carl Schreck’s lab in Oregon State’s Department of Fisheries and Wildlife, are documenting Pacific lamprey spawning grounds as part of a three-year study funded by the Columbia River Inter-Tribal Fish Commission. “The goal of our research is to first ensure the persistence of lamprey in the Willamette Basin and, second, to restore population levels sufficient to meet historic human use,” says Schreck. “To do this, we need to have some understanding of the reproductive capacity of the Willamette population, and bottlenecks to reproduction need to be identified.”
For at least two decades, the tribes have been leading the charge on behalf of lamprey, which the Grand Ronde Indians call skakwal and the Umatillas call ksuyas. As one of the “first foods” of Northwest Indians (along with salmon, elk, huckleberries and camas bulbs) lampreys hold a place of high honor in tribal culture. The fish’s seven gill slits have religious and cultural significance that echoes through many native traditions (see “To Bring Back a Native Fish,” by Gabe Sheoships).
But outside Indian culture, Pacific lampreys have a PR problem. “The Euro-American perception (is) that lampreys are pests,” David Close, a fisheries biologist and member of the Cayuse Nation, wrote in a 2002 report for the Confederated Tribes of the Umatilla. “We suggest that cultural biases (have) affected management policies.”
Close, who now leads the Aboriginal Fisheries Research Unit at the University of British Columbia, offered some staggering statistics to bolster his critique of lamprey management. In 1966, nearly 47,000 lampreys were counted in the Umpqua River at Winchester Dam. By 2001, the count was 34. In 1963, more than 49,000 lampreys were counted in the Snake River at Ice Harbor Dam. In 2001, the number was 203.
“If you had to identify one smoking gun,” says Schreck, “it would be dams.” The stair-step fish ladders in the Columbia Basin’s vast network of hydroelectric dams were designed for salmon, which are powerful jumpers. But lampreys, whose suction-cup mouths are not adapted to right angles, are stymied. According to Schreck, it wasn’t an oversight. “The fish passages were built deliberately to exclude lampreys,” he says. “Back then, people thought lampreys were outcompeting salmon.”
Deliberate poisoning also decimated Pacific lamprey in the last century. “From the late 1940s through the 1980s, the Oregon Fish Commission used rotenone in basins throughout the state to eliminate non-game species including Pacific lamprey,” reports a 2004 Northwest Power and Planning Council document. “This practice no longer occurs today, but with up to seven year-classes of Pacific lamprey present in freshwater at any one time, the intentional fish kills of the mid-1900s likely severely impacted Pacific lamprey populations.”
The Oregon Hatchery Research Center in the Alsea River Watershed recently built one of the Northwest’s first lamprey-friendly fish ladders. And a standing-room only crowd at the OSU-sponsored International Conference on Engineering and Ecohydrology for Fish Passage in June heard from Northwest scientists who are studying new designs for lamprey passage.
Even as wildlife conservation groups make herculean efforts on behalf of charismatic species — the majestic Chinook salmon, the adorable panda bear, the mysterious blue whale — the Pacific lamprey has drifted ever closer to the endangered species list practically unnoticed — except by the tribes and a few OSU fisheries biologists. David Close, who was a researcher at Oregon State in the 1990s, was one of the first scientists to sound the alarm in the fisheries community. Ever since, researchers have been scrambling to learn as much as possible about the primordial survivor before it’s too late.
For the Pacific lamprey, the “pest” perception couldn’t be further from the truth, these scientists stress. Unlike the invasive sea lamprey, which is overtaking native trout in the Great Lakes, the Pacific lamprey is exquisitely adapted to the Northwest river ecosystems it has shared with salmon, steelhead and rainbow trout for thousands of years. In fact, compared to lamprey, the more charismatic aquatic species are planetary newcomers. Modern fish — the jawed kind — don’t show up in the geologic record until the Devonian Period late in the Paleozoic Era (“Paleozoic” derives from the Greek, meaning “ancient life”) — about 400 million years ago. Lamprey, on the other hand, made their appearance 100 million years earlier, during the Cambrian Period at the very dawn of prehistory. And dinosaurs? Next to lamprey, the fearsome reptiles seem positively modern, not lumbering onto the scene until the Jurassic Period, 250 million years after lampreys first plied the primordial seas.
Schreck notes that lamprey parasitism is rarely fatal to the host. And there’s another side to the story, one that actually makes lampreys beneficial to salmon: lampreys are a sought-after delicacy for sea lions, seabirds, otters and other animals that eat salmon.
“Lampreys are a buffer against salmon predation,” says Schreck. “They’re the most energy-laden fish, very, very rich in oil, which makes them the preferred food of salmon predators. They’re sort of like the cheeseburger — the bacon cheeseburger — of the food web.”
A hungry sea lion will eat 30 lampreys to every salmon, studies have found. Caspian terns, which have been gobbling up juvenile salmon on the Lower Columbia, also prefer to feed on lampreys — when they’re available. “As the lampreys disappear, predators eat whatever’s around, and that happens to be salmon,” says Schreck.
Buffering salmon predation, however, is only one ecosystem talent of the Pacific lamprey. After hatching, young lampreys dwell unseen in river-bottom muck up to eight years or more. Blind and nocturnal, about half the size of a No. 2 pencil, these lamprey larvae play an important role in stream ecology — a role that has earned them another nickname, the “river worm.”
“They churn up the soil in the river, just like an earthworm would in your garden,” says Schreck. “This allows for cycling of nutrients up through the food chain.”
“Right, they burrow in fine sediments,” adds fish biologist Lance Wyss, a former researcher in Schreck’s lab who now works for the Calapooia, North Santiam and South Santiam watershed councils. “They feed on fine organic material, adding to the transfer of nutrients between the water column and the substrate. It’s good for the entire riverine food network.”
But within those fine sediments, pollutants lurk. In urban corridors, especially, contaminants from cars and industry — manmade chemicals that run off freeways and parking lots into the watershed — create a toxic brew for streambed-burrowing organisms. In one study, baby lampreys were introduced to sediments from the Environmental Protection Agency’s Super Fund cleanup site at the Port of Portland. The larvae quickly burrowed in. Even more quickly, they burst back out, coughing up the sediment, Schreck says. They refused to burrow again.
Tickling Baby Lampreys
A trio of OSU researchers line up shoulder-to-shoulder on the edge of a quiet pool in the Marys River, which tumbles eastward out of the Coast Range. It’s early summer, 2013. The guy in the center, grad student Gabe Sheoships, looks like a character from Ghostbusters strapped into a battery-powered electrofishing backpack the size of a small suitcase. In each hand, he holds a long metal pole with an electrode at the end. Lowering the probes into the stream, he delivers a mild zap near the river bottom, where fine sediments provide nourishment and hiding places for lamprey larvae. “To the fish, it just feels like a tickle,” says Sheoships, whose Cayuse and Walla Walla ancestors fished the Columbia long before white settlers came across the Oregon Trail. That tickle is enough to startle the fish into popping up from the mud.
His two companions, Luke Schultz and Mariah Mayfield, flank him, gripping dip nets. Then they begin the “lamprey shuffle,” a sideways scoot across the pool that looks a lot like a country-and-western line dance.
“There’s one!” calls out Schultz. Mayfield lunges, thrusting her net into the stream and scooping up a four-inch brown baby lampreys, the larval form that scientists call an “ammocoete. “
“Got ‘im!” she announces triumphantly. Turning her net inside out, she releases the tiny fish into a water-filled bucket on the bank. After zigzagging across the pool until they’ve sampled every likely hiding place, the three researchers — who call themselves the “Lamprey Posse” — weigh and measure each of the 100-plus larvae they’ve caught and return them to the stream.
As a tribal member, Sheoships has a personal stake in the research. “The lamprey is a cultural keystone for the tribes of the Columbia Plateau,” he says. “Lampreys have gotten a bad rap. The terms ‘parasite’ and ‘bloodsucker’ get thrown around a lot.” Then he jokes, “It’s not the lampreys’ fault that they got hit with the ugly stick.”
Schultz, who hails from the Midwest where the invasive sea lamprey is decimating sports fisheries, hears similar terms of disparagement when he tells the folks back home that he’s trying to save the Pacific lamprey. “They think I’m a maniac,” he says. “They don’t understand that the situation is completely different here. Our lampreys are native. They play an important role in ecological functioning, and also in cultural preservation.”
The researchers’ data on Pacific lamprey populations in the Marys, the Luckiamute and several other Willamette River tributaries will give scientists and tribes a better picture of the fishes’ status in order to inform conservation efforts. The findings also will fill in data gaps needed for a possible listing under the federal Endangered Species Act.
“We don’t want another snail darter or Devils Hole pupfish — a species nobody’s ever heard of till it’s endangered,” says Corvallis filmmaker Jeremy Monroe of Freshwaters Illustrated, whose recent short documentary, The Lost Fish, portrays the Pacific lamprey’s plight. Pacific lamprey will play a leading role, too, in Monroe’s upcoming feature-length film Willamette Futures about “the fate of Oregon’s big river.”
After years foraging in the muck, the little lampreys in quiet tributaries will emerge to undergo a metamorphosis. Schreck likens the transformation to the better-known tadpole-to-frog changeover. The larvae will acquire eyes (beautiful blue eyes the color of tropical seas). They’ll grow razor-sharp teeth and a rasping tongue and ride the river currents out to sea. By the time they return to freshwater to spawn, they’ll be 500 times bigger, having ballooned from pencil-length to yardstick-length in two or three years.
Scientists like Schreck hope research can help these emissaries of the Paleozoic survive the Anthropocene.
“Thirty-five years ago when I started my career, there were zero papers on lamprey presented at meetings of the American Fisheries Society,” he says. “These days, there are whole symposiums on lamprey.”
All the attention just might be making a difference. “So far this year, 908 lampreys have passed Winchester Dam on the Umpqua, where only 34 passed a dozen years ago,” Schreck reports. “Maybe something good is happening for lamprey.”
Lamprey prefer stream habitats that are under threat (OSU news release, 2-10-15)