Tribes, biologists work to halt slide of lampreys

  • Mon Aug 13th, 2012 9:42pm
  • News

By Bill Sheets Herald Writer

MUKILTEO — If there were beauty contests for sea life, they likely would not be won by Pacific lampreys.

Lampreys, a type of parasitic eel, have a big, toothy suction cup for a mouth that sucks blood and bodily fluids from fish and whales. They’re long, slick and snake-like.

If they look prehistoric, it’s because they are. They’ve been around for 450 million years, since before the dinosaurs.

And yet there’s big effort under way to help them survive.

The Pacific blue lamprey is in decline in the Columbia River system, where the species has been harvested for food, ceremonial and medicinal purposes by Indian tribes for centuries.

Now, the National Oceanic and Atmospheric Administration is working with the Confederated Tribes of the Umatilla Indian Reservation near Pendleton, Ore., to study ways to increase the lamprey’s numbers, and they’re doing it in Mukilteo.

About 5,000 eggs were taken from female lampreys earlier this year. The larvae are growing in tubs of fresh water in varying conditions, such as with mud, sand or nothing added, to determine the environment in which they can best thrive.

Staff at the NOAA center in Mukilteo, housed in former Air Force buildings on the waterfront, do most of their research on how contaminants affect saltwater fish. The lamprey project is the first of its kind at the lab, said Mary Moser, a research biologist with NOAA fisheries who is working on the project with the tribes.

“You can’t create environments like this in the wild,” she said.

The translucent larvae are about two months old and a centimeter long, said Jerrid Weaskus, lamprey technician for the Umatilla tribes. When they’re fully grown, each lamprey will be about 2 to 3 feet long, a few inches around and weigh about a pound.

Moser and tribal researchers worked last week to count and measure the larvae, or ammocoetes, as they’re called.

“It’s a very tedious process,” Moser said.

The wiggly ammocoetes are extracted from the tubs with a basting tube and put in petri dishes where the water is diluted with an anesthetic to slow them down so they can be measured.

Once the best environment is determined, it’s hoped they can be planted in Columbia tributaries, both for harvest and research, tribal members said.

Lamprey are like salmon in that they hatch in streams, migrate to the sea and return to spawn. But they have longer life cycles. While salmon head for saltwater within a year and return within five years, lamprey linger in fresh water for two to three years, head to sea for three to five years, and can live up to 10 years, Moser said.

Lamprey larvae burrow into sediments and filter feed, which helps clean the water but makes them more susceptible to the effects of pollution, according to NOAA.

As recently as 2002, up to 200,000 lamprey were counted returning from the sea at Bonneville on the Columbia, said Aaron Jackson, lamprey project leader for the Umatilla tribes.

For the five years leading up to this year, fewer than 50,000 lamprey were counted, he said. The dams along the Columbia weed out about half of the lamprey that return, preventing them from spawning, according to Jackson. Some fish ladders have recently been built for lampreys to combat the problem. Other factors, such as habitat loss, might be contributing to the decline as well, officials said.

And, not unexpectedly, some of the growing eels are eaten by sturgeon and herons.

Lampreys use their sucker-like mouths to attach to rocks under the water, Weaskus said. The Umatilla tribes harvest them by pulling them off rocks at Willamette Falls when the water recedes in July.

When harvesters arrive, the lampreys in the water try to swim away, but other tribal members are there waiting for them with nets.

The tribes keep their harvests down to avoid depleting the species, Weaskus said. This year they took about 600, he said.

The eels are filleted and cooked over an open flame or smoked.

“It’s an acquired taste,” Weaskus said. “It’s pretty oily.”

Lampreys live in Puget Sound as well as local rivers, but don’t seem to be prominent in the diet of coastal tribes, Moser said. The status of lampreys in the Sound hasn’t been extensively studied, she said.

On the Columbia, it’s hoped that lamprey planted in tributaries can help researchers determine exactly how many are stopped by the dams and what other factors might be in play, Jackson said.

He said the tribes have received a grant of up to $100,000 for the project from the federal Bonneville Power Administration, which operates the dams on the Columbia.

Of course, it’s also hoped the project can increase the lampreys’ numbers for harvest.

“Our plan is to think seven generations ahead,” Weaskus said. “That’s what this is all about.”

Bill Sheets: 425-339-3439; sheets@heraldnet.com.