If you live in the Pacific Northwest you probably have have heard about how hatchery fish are reducing the fitness of the overall population and competing with wild-spawned fish, diluting their genetics and in general harming wild salmon recovery. Many wild fish groups argue that for this reason hatcheries should be shut down. Sport, commercial, and tribal fishers argue that hatcheries are necessary parts of their cultures, livelihoods, and salmon recovery. I think we all share the same goal in having healthy, fully wild runs of salmon and steelhead that meet the cultural and economic needs of our region. I believe an immediate hatchery shutdown would be like removing life support due to a rash from the breathing mask while the patient was still recovering from pneumonia.
After reading a lot of scientific papers, I’m of the opinion that the majority of harms to our wild salmon and steelhead population comes from sources like dams, pollution, high predator populations, and climate change. With that said, there is progress to be made in improving the diversity of fish genetics in the hatcheries. Diverse gene pools create a broad range of growth patterns, and behaviors that can allow some fish to be more successful in the face of these other major challenges. Those fish pass on their successful traits to their young.
The genetic problem with traditional hatchery programs is that they use hatchery spawned fish for their brood stock. This means that the hatchery will only have the genetics it started with. With low returns they lose some of those traits with each generation, resulting in lower and lower returns. The fish from that hatchery are end up being closely related in the same way that all Labrador retrievers are closely related. This works well if the world is full of couches and duck blinds. It gets to be a problem if you need a sled pulled or a burglar chased off.
Broodstock programs address this issue by intentionally not using hatchery spawned fish. They rely on the stream environment to provide wild salmon and steelhead with a lot of different genetics. The fish are transported live to the hatchery and spawned. Species like steelhead that can spawn multiple times are returned directly to the streams when the hatchery is close to the coast like at Quinault Nation and those on the Wilson River. Some programs, like those operated by the Yakima Nation, will hold spawned out steelhead and feed them up before release in order to improve their chances of returning to spawn again.
These programs have shown quite a bit of success in improving survival and return. There is research indicating that the hatchery environment contributes to decreased survivability. That will be a post for another day however. In the meantime, the video from a great group called hatchery/wild co-exist shows the benefits of these broodstock programs.
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