Each year, hatcheries release millions of chinook into the Columbia River system in a bid by state game managers to save wild stocks of this salmon. The fish there is so beleaguered that many of its populations, threatened with extinction, are protected under the Endangered Species Act. A new study now offers evidence that hatchery fish may be hastening the wild stocks’ demise.
Log in
Subscribers, enter your e-mail address for full access to the Science News archives and digital editions.