BOISE, Idaho — For years critics have included hatcheries in their list of problems for wild salmon and steelhead.
Among the gripes: hatchery fish weaken the species’ gene pool by breeding with wild fish. Scientists at a laboratory in Idaho are determined to change that.
The Hagerman Fish Culture Experiment Center is located in the Southern Idaho desert. The location is no accident. Water pours from the rock walls of the deep canyons carved 15,000 years ago by the Bonneville Flood. The water comes from the giant underground aquifer that supplies clean, fresh water that maintains a constant 60-degrees year round.
This is the perfect place to raise fish. There are several trout farms along this section of the Snake River. It’s also home to the U.S. National Fish Hatchery and the small Hagerman Fish Culture Experiment Center. The center is operated by the University of Idaho, the U.S. Department of Agriculture and the Columbia River Inter-Tribal Fish Commission.
The tribes set up shop here about a decade ago to research salmon and steelhead genetics. Shawn Narum was the first researcher hired by the tribes. Today he is the lead research scientist. Narum explains that the tribes have spent years researching ways to reduce the genetic effects on natural salmon and steelhead populations.
“What they are trying to do is reform hatchery practices so they are having less genetic effects on these natural populations,” he says.
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Northwest waters are awash with controversy when it comes to wild salmon’s ability to survive with hatchery fish in their midst. Decades ago, hatcheries were thought to be the perfect solution to sustaining the iconic runs of salmon and steelhead as river-blocking dams were constructed throughout the Northwest.
But by the 1990s, criticism of hatcheries continued to plague the Northwest. When bigger hatchery-reared fish are released into rivers, they gobble up juvenile wild fish and compete for prey. There was also mounting concern that fish in the crowded confines of hatcheries were more likely to spread disease.
Hatchery fish are less likely to possess the traits rewarded by survival in the wild. They are fed on a regular schedule, protected from predators, and grow larger than their wild counterparts. Later in life, they can end up mating with wild fish, passing along inferior genetic traits to offspring.
Nick Gayeski is the staff scientist at the Wild Fish Conservancy in Washington state. He expressed fears that after several generations. There won’t be any truly wild salmon and steelhead left in the Northwest.
That’s because they will all be at some point have bred with progeny that have run through the hatchery for one or more generations, Gayeski says. “And if their fitness — reproductive fitness — drops low enough, then you might have a population that truly can’t sustain itself.”
Sara Thompson is with the Columbia River Inter-Tribal Fish Commission. She thinks researchers will be able to prove critics like Gayeski wrong. The key is improving hatchery programs to ensure hatchery fish maintain the traits necessary to survive in the wild.She says they are using the best research tools and technology available to help inform those in charge of hatcheries do a better job. The research is all conducted in Idaho’s Hagerman lab.
The laboratory uses robots to do most of the labor intensive work. It reduces the potential for human errors and machines can do all the testing faster. One machine the tribes use can process up to 1,000 fish samples at a time. It will tell scientists which fish were hatchery-raised. It can even tell if the fish has a parent or a grandparent from a hatchery over many generations.
If researchers like Narum can pinpoint which hatchery fish are carrying the best genetic traits, they can help hatchery managers become more selective about which of these fish are used to repopulate hatchery stock.
Gayeski, the wild fish advocate and scientist, isn’t convinced that other scientists can build a better hatchery fish. And, he says, this type of research isn’t new. A federal scientific review panel spent nearly a decade researching 178 hatcheries in the Northwest. It made recommendations in 2009 that Gayeski says should be followed immediately.
The panel’s recommendation that Gayeski would most like to see followed? Limits on the number of fish raised in hatcheries and released into the wild.
Thompson, the tribal fish commission spokeswoman, says the tribes differ from non-tribal fish advocates when it comes to hatcheries. The return of robust salmon runs isn’t merely an ecological goal they can wait on for decades. Salmon and steelhead represent a sacred First Food. They are a primary source of nutrition — as well as a treaty-guaranteed right.
To put it more simply, tribes represented by Thompson’s commission just can’t sit by while nature returns enough salmon to their nets and dinner tables. That explains why hatcheries are vital to tribes trying to bring back salmon in abundant numbers. And if they’re successful, the Columbia River tribes’ Hagerman lab research will give hatchery managers new ways to reduce the genetic impact their fish have on wild salmon and steelhead.
If more hatchery fish can pass on the genetic traits to evade predators and compete for food, there will eventually be stronger runs — fish that can survive the journey to sea, years in the ocean, and the return upriver to reproduce.
That means less dependence on hatcheries.
And that’s something both hatchery critics and the tribes would like to see happen.
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