Are hatcheries killing endangered fish?

Nature brings troubling news from the saving endangered species front. A study has shown that fish raised in captivity really don’t do well in the wild:

“What’s starkly clear,” says Blouin, “is that using hatchery fish to produce another generation of hatchery fish causes a very rapid decline in fitness.” Simply raising fish in captivity cuts their reproductive success by 15%. As the researchers report in this week’s Science, having one captive parent in addition to being raised in captivity will reduce reproductive success by an additional 45%, thanks to genetic effects.

Researchers say this reproductive problem may correct itself after a couple of generations have died out reproduced in the wild. But they won’t know until they see it happen.