Oregon Public Broadcasting

New research published Monday suggests that hatchery fish may be adapting to captivity -- making them less equipped to take on life in the wild.

Mark Christie is finishing his postdoctoral research at Oregon State University. His research was published in the Proceedings of the National Academy of Sciences. He did genetic analysis on more than 12,000 hatchery-raised and wild steelhead in the Hood River.

He found that in captivity, the hatchery-born fish had nearly double the reproductive success as wild fish. Christie says that shows hatchery fish are adapting to life in captivity -- and quickly.

"That's one of the remarkable findings of this paper is how quickly this process is occurring," Christie said.

But the traits that make a fish do well in a tank with thousands of other fish don't necessarily help that fish do well in an open river. Hatchery fish are used to supplement wild populations. Many wild populations are in decline.

Research shows that fish raised in hatcheries don’t do as well as wild fish, once they're released.