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Just One Generation in a Salmon Hatchery Ruin Salmon for Thriving in the Wild by Ralph Maughan The Wildlife News, January 10, 2012

Most people know the inspiring story of the salmon. Hatched in the gravel of a rushing mountain stream, the smolts are pulled by the waters downstream past logjams, lethal crevices in the rock, and sometimes into side pools from which there is no escape.

Mile-after-mile, sometimes many hundreds of miles, the river grows but nowadays too often the smolts die in the slack waters of a reservoir, plucked out by predatory birds or fish or simply by their own biorhythms, now turned against them. They begin to turn into a salt water fish hundreds of miles from the sea because of the lack of a current to pull them promptly to the ocean.

Those few that still make it to the sea grow big but have to dodge their natural predators, such as orca, and sea lions, and artificial dangers such as pollution and parasites from penned salmon "farms". Over the years the numbers of wild salmon have dwindled. Managers (and don't all wildlife today have to be managed?) have decided to build hatcheries, trying to flood the streams with so many smolts that it doesn't matter if only 0.1 % fight back upstream to return to spawn. Those that do now are usually spawned in an artificial place by humans. The new hatchery smolts live an easy life at first, but scientists have now found that this human easychair likely ruins a run's fighting spirit, their natural ability to survive, in just one generation. In fact, those most adept at hanging around the hatchery do slightly better surviving outside than the natural born fighters.

Related Pages:
Hatcheries Change Salmon Genetics After a Single Generation by Staff, Science Daily, 12/20/11
Agencies Scoping Plan For 'Hatchery Effects Evaluation Team' by Staff, Columbia Basin Bulletin, 1/13/12