Students sniff out science behind fish hatchery

The seventh-graders submitted their names if they wanted to take the field trip.

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Lyons Ferry Fish Hatchery specialist 3 Steve Jones holds a basket of eggs out of the water to allow newly hatched fish to move into the water as (left to right) John Edson, Melissa Holecek and Lonnalisa Buettner watch. Edson is bus driver for Walla Walla School District, Holecek works at Walla Walla Community College's Watershed Ecology program, and Buettner is a seventh-grade student at Garrison Middle School.

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Garrison seventh-grader Maya Hull peers into a pond trying to locate young fish during a recent tour of the Lyons Ferry Fish Hatchery.

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Newly hatched salmon are barely recognizable, as their tails and eyes denote their length. The fish will not eat for four weeks as they absorb their yolk sac (the red bulb).

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After selected fall chinook salmon have been killed and eggs and milt (sperm material) removed, they are collected on a table for measuring, tagging and determining whether they were previously tagged.

STARBUCK - Forty Garrison Middle School students from Walla Walla followed the life cycle of salmon, steelhead and rainbow trout during a recent tour at Lyons Ferry Fish Hatchery.

The frosty air didn't stifle the distinct "fishy" odor on the hatchery grounds.

Small wonder, considering there were hundreds of thousands of fish in the ponds and "lakes" at the hatchery.

The students didn't seem to notice the smell as they focused on information given by hatchery employees, and peered into fish pens to spot the growing salmon and steelhead.

Mike Birely, executive director of the Tri-State Steelheaders, and Luke Hamada, Garrison science teacher, organized the tour.

The seventh-graders submitted their names if they wanted to take the field trip, and 40 names were drawn, Hamada said.

When the students toured the facility, hatchery workers and scientists were working with fall chinook, returning to spawn. Most of the fish, now weighing an average of 12 to 15 pounds, left the hatchery on the Snake River as fry, and had made their way to the Pacific Ocean and back to where they were hatched.

The returning fish were trapped and held in pens for six to seven week then anesthetized and lifted by an elevator onto stainless steel tables in the spawning room.

Students watched from a viewing window as workers killed the fish with a short aluminum bat, then cut them open and extracted eggs (roe) from the females and sperm (milt) from the males.

Although some of the students were aghast at the treatment of the fish, they were assured the fish would have died naturally soon after they spawned had they laid their eggs in a stream.

Later in the day students visited some natural spawning sites on the Tucannon River where they saw where fish had created nests and laid their eggs.

In the spawning room, the fish carcasses undergo a number of procedures before being placed in a dumpster awaiting burial.

The fish are scanned for identification chips or wires, which identify their birthplace and birth year. Roe and milt from each fish is given an identification number, so the material can be pulled if tests show the donors are diseased.

Some fish's heads are removed so scientists from the University of Idaho can examine the fish's ear stone (otolith), a bone that reveals as much about the fish as tree rings do about a tree.

Scientists are able to determine from the bone how much time the fish spent in freshwater and in saltwater, its age and rate of growth.

Students were interested in seeing the coded wire tag removed from a salmon's snout, so tiny it was hard to see with the naked eye. A hatchery employee placed the wire under a microscope, and was able to read a number from the wire.

Harvested and fertilized eggs are raised in trays or baskets in the incubation room. It takes the eggs four weeks to "eye up" and be strong enough to be handled, hatchery complex manager Jon Lovrak told the students.

After another two weeks as eggs, the fish begin to hatch. About 10 weeks after spawning the fish are transferred to raceways where feeding begins.

Each of the raceways and ponds are vacuumed weekly with waste going to an abatement pond, Lovrak said.

The Lyons Ferry Hatchery fish are fortunate to be served by a well that consistently produces water that is 53 degrees.

The hatchery was built by the U.S. Army Corps of Engineers in 1982 as part of the Lower Snake River Compensation Plan to restore dam-related losses of steelhead and chinook salmon. It is the only hatchery producing Snake River fall chinook salmon.

Lyons Ferry and Tucannon fish hatcheries also raise about 320,000 rainbow trout each year for stocking in lowland lakes in Washington and a few streams in North Idaho.

Students got close-up and personal with some of the rainbow trout, the ones that perhaps could be called overachievers in the fish world. A round tank held a number of "jumbo" rainbow trout, some weighing as much as three pounds.

Fish hatchery specialist Steve Jones scooped a cup of pellets out of a container and passed it to the students, warning them to stand back or they might get wet.

Although the fish didn't leap out of the water for the food, they managed to splash significant spray to create shrieks and laughter.

Jones took the students to a room where fish eggs were held in baskets. As the fish hatched, they wriggled their way out of the baskets and into the cement channels where they rested in a large group, looking like an orange mottled mat with black polka dots (eyes.)

At this stage the young fish are called alevin, and when they absorb their yolk sac and are ready to start eating, they are called fry. As the fry grow to about two inches, they are called fingerlings, and they are voracious eaters.

The fish at the hatchery eat 275,000 pounds of food a year, most blown into the ponds from a truck, Jones said.

The Tri-State Steelheaders help teachers set up tanks for classrooms to raise fish as a learning project, and Bireley said "it occurred to me we have this great resource here. It would be good to expose students to the process."

The hatchery staff was receptive, and Bireley combined a grant matched by the Steelheaders, and donated staff time from agencies to fund the field trip.

The field trip also had a career awareness component. Most of the people working in the hatchery have college degrees, the students learned.

When asked what they noticed about the workers in the spawning room, one student responded, "They looked happy doing it."

Following the hatchery tour, the students were bused across the river to the Lyons Ferry Marina and KOA, where Marina operators Jim and Angela McArthur served sack lunches.

After lunch, McArthur talked to the students about the economic benefits of keeping fish in the river.

"This place is here because of recreation. Having healthy runs of fish is really important to us," McArthur said.

"We want these steelhead, and we want these salmon to thrive," he said.

The marina provides jobs for five to seven people, McArthur said.

Glen Mendel, of the state Fish and Wildlife Service, told the students the fish are valuable to the local economy. Each steelhead is worth about $2,000, with fishermen and other recreationists generating $25 to $30 million annually into the economy.

Besides the marina, the Snake River fisheries contribute to other businesses in the area, included RV parks, grocery stores, a tackle shop in Starbuck, and fuel suppliers, Bireley said.

For Hamada, the trip exposed students to new ways to view science and scientists.

"I thought it was a good experience, and I think it's really good, because the kids think science is people sitting in a lab. There are lots of cool jobs I think the kids would be interested in if they pursue a job in science," he said.

Carrie Chicken can be reached at cec@innw.net or 522-5289.

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