A leap in lampreys — rebound for odd fish
Unlovely creatures aid environment
POTTER VALLEY, Mendocino County — This year’s historic gush of water through California’s rivers brings the dawning of a renaissance for lampreys, a peculiar fish that migrates upstream to spawn but without the fanfare of its salmon and steelhead compatriots.
On a recent afternoon in wooded hills some 150 miles north of San Francisco, dozens of lampreys — commonly called eels because of their snake-like figures — were doing something that can be startling to the uninitiated: They were using their sucker mouths and thorny teeth in an attempt to hoist their slippery bodies up and over the concrete face of 50-foot Van Arsdale Dam.
“Because they’re so prehistoric and creepy-looking, they’re scaring people.” Jana Frazier, fish hatchery tour guide
The climb at the Eel River, an appropriately named waterway that is just one of many the fish are storming this summer after years in the open ocean, marks the end of their farreaching journey to the mountains to reproduce.
Protecting the unusual creature and its diminishing river runs across the West is the job of a group of researchers who are based on the Eel River but tromp through forests around much of the state. And this year, they’ve got their hands full.
“We really didn’t think we’d get this many of them,” said Damon Goodman, a biologist with the U.S. Fish and Wildlife Service, as he monitored the progress of lampreys last week at Van Arsdale Dam. “We’re getting calls from all over the place now.”
From San Luis Obispo Creek to the Sacramento Valley’s Feather River, reports are coming in of lampreys in numbers not seen for years, if not decades. While the critters’ nocturnal life and brown, camouflage bodies make them largely invisible to even the most veteran fishermen and paddlers, their sheer abundance has led to more sightings — and inevitably, more questions from those who haven’t seen one before.
Far from Mendocino County in the northern Sierra foothills, where the fish have been spotted for the first time in 30 years in some places, reaction has varied from awe to fear.
“Because they’re so prehistoric and creepy-looking, they’re scaring people,” said Jana Frazier, who leads tours of the state-run fish hatchery on the Feather River near Lake Oroville. “Most people have never seen a lamprey, and they want to know if they’re going to be attacked.”
Watching the lampreys scale the side of Van Arsdale Dam, or opt for an adjacent fish ladder built for spawning salmon, Goodman acknowledged that the fish are a bit off-putting. They use their round, funnel-like mouths and sharp teeth not only to climb but to latch onto other fish, even whales and sharks when they’re at sea, and feed on their blood.
An invasion of lampreys nearly a century ago in the Great Lakes literally sucked the life out of the commercial fishing industry. But Goodman, speaking while plucking a lamprey from the fish ladder and holding it in his hands, said there’s nothing to fear in California.
The Pacific lamprey, native to the state and dating back to before the dinosaurs, doesn’t bite humans and provides a slew of environmental benefits. It’s food for the likes of bears and bald eagles, he said, and delivers nutrients when it dies and decomposes in the riverbed.
While biologists believe this year’s surge of lampreys is tied to high river flows after a near-record wet winter, the fact is they don’t know for sure. Unlike salmon and steelhead, lampreys are not a major focus of fish research. Little monitoring has been done of the commercially valueless fish, and there’s not a lot of historical data.
“Our understanding of lamprey biology is like 50 years behind (that of ) salmon,” said Goodman, whose team is one of few in the state dedicated entirely to learning more about the fish. “We’re just starting to get a handle on the issue and understand how important they are.”
The lack of attention means lampreys have missed out on river management practices that have helped other fish migrate upstream, like timed water releases from dams and the construction of fish ladders.
According to Goodman, lampreys aren’t very good at getting up the fish ladders — built more for jumping than climbing — posting a success rate of just 6 percent at Van Arsdale Dam. Those that do navigate the channel, which runs a few hundred feet, take two weeks on average.
And while lampreys have historically traveled to much higher spots in the mountains than salmon and steelhead thanks to their climbing prowess, they’re cut off today from a lot more of their native habitat than the other fish. Goodman estimates the lamprey population is half of what it once was.
An effort to list the fish as federally endangered and win special protections failed a little more than a decade ago. Though the lamprey’s distribution across waterways is substantial — it is generally found wherever salmon and steelhead live, from California to Alaska and around the Pacific rim — its numbers remain uncertain.
American Indian groups across the Northwest have been particularly concerned about the animal’s plight. The lampreys continue to be a traditional and beloved food source, rich in protein and available to fishermen when salmon are not.
“My grandma would tell me that her family would camp on the river and come home with potato sacks full of eels,” said Ted Hernandez, 49, tribal chair of the Wiyot community, whose members still live and fish near the mouth of the Eel River, in Humboldt County about 150 miles from Van Arsdale Dam. “But like with salmon, we’re worried abut the population of the eel. We have some of us who live to be 100 years old, and they say it’s from the eels.”
The efforts of Goodman’s team to halt the lamprey’s decline focus less on government intervention and more on finding ways for the fish to overcome river obstacles. Over the past couple of years, they’ve tried everything from running small culverts around dams to putting pickle barrels in fish ladders to help lampreys pull their way upstream. What works best, they say, are simple PVC tubes that serve as tunnels around trouble spots.
“This is something that’s applicable in other areas having lamprey issues,” Goodman said as he pointed to his 250-foot-long experimental conduit up and around Van Arsdale Dam. “Eventually, for a long-term solution, we can implement something more sturdy.”
This year, so many lampreys have been migrating up the 200-mile Eel River that Goodman and his team are installing a second PVC tube for fish passage.
The addition follows actions the group has taken elsewhere to accommodate large numbers of lampreys. In San Luis Obispo, the researchers helped restore a lamprey run that had virtually disappeared in a creek through the city’s Mission Plaza park a few years ago. A newly-modified weir, they discovered, was hampering upstream migration, so they installed a ramp for climbing across the hurdle.
“These are not major things we need to do,” Goodman said.
After inspecting the PVC tube at Van Arsdale Dam, where Goodman has counted more than 3,000 lampreys moving upriver this year, he turned his attention downstream. He bushwhacked to a vantage point where he hoped to see how many lampreys were stopping short of the dam. Walking and wading, he finally arrived at a shallow pool that looked hospitable to fish.
At the sandy river bottom, a few male lampreys were waiting for females in nests made of small, round stones, like an underwater fire ring. The females will lay their eggs here for the males to fertilize, Goodman said.
The fish appeared alert and lively, whipping around the bottom of the river, even in the heat of the afternoon when they’re usually hidden beneath the mud. But these moments are among their last, Goodman said. The lampreys die shortly after they spawn.
“Look at them dancing around in there,” he said. “There’s just not a lot of places you can observe this.”