A professor at Oregon State University is leading a series of studies to breed hatchery-raised steelhead that are more like wild fish.
The biggest hatchery-raised steelhead trout survive the swim to the ocean. But once in the wild, they’re less likely to stay fit and reproduce. OSU biology professor Michael Blouin is testing ways to make a hatchery more like nature, so steelhead adapted to life in a tank don’t genetically impact wild fish.
“In the wild," he said, "[a] little fish pops up out of the gravel. He has to defend a territory. He has to get food which is scarce, and he has to do all this without getting eaten by predators.”
His lab tried lowering the fat content in the food, but that didn’t favor the leaner and “shyer” fish which thrive in the wild. Blouin said they’ll try things like mixing up feeding schedules, and circulating the water, so the young fish have to swim constantly. If they find a treatment that works, they’ll try it at production scale.
More about the research is on OSU's newsroom, here.