About 400 hatcheries operate throughout the West Coast today. In the Columbia River basin, about 180 hatchery programs breed millions of fish in plastic trays, transfer them to rearing "ponds," and then release them to join wild ones travelling down river to the Pacific Ocean, to later return to the same river to reproduce and die. Most hatcheries are devoted to turning out fish for fishermen to catch.
Over the past few decades, numerous studies have shown that breeding in captivity makes for fish that are less capable of producing offspring. Hatchery fish also out-compete wild fish for food as they inundate rivers and oceans. Their presence lowers the number of offspring produced by wild populations, disrupts local adaptations acquired over centuries, and leads to loss of genetic diversity.
Hatchery proponents acknowledge the risks of artificial propagation. They say reforms are already in the works. Many hatcheries now use native breeding stock. They also avoid mixing hatchery and wild fish on the spawning grounds. Other hatcheries have been scaled back or turned off.
But "much of the effort is to try to figure out ways to both maintain significant hatchery production and limit impacts to wild populations," said Mike Ford, conservation biology division director for NOAA Fisheries' Northwest Fisheries Science Center in Seattle.
Ford and other proponents say artificial breeding has benefits: it can bring back fish to rivers where they have been wiped out. That's already happening on the Hood River, where the Confederated Tribes of Warm Springs and Oregon biologists have reared Chinook salmon for over two decades. Their population has increased, enough to re-establish limited fishing for the tribe and other fishermen.
But hatchery fish and their progeny now dominate the run, just as they do on the Snake River, where another tribal hatchery has vastly increased the numbers of returning fall Chinook salmon.
"If the only societal goal for salmon was conservation and recovery of wild populations," Ford said, "I think hatcheries would play a much more limited role than they do now."
- Two Christian ministers refuse to perform...
- Virus expert sees 'silver lining' in Ebola...
- Oscar Pistorius starts serving 5-year prison...
- Jodi Arias sentencing retrial opens in Arizona
- The poorest of the poor in many Third World...
- Indiana man's confession leads to 7 bodies
- This type of high school can increase your...
- Fire exposes illegal Chinese factories in Italy
- Two Christian ministers refuse to... 53
- New Ebola 'czar' knows Washington, but... 22
- Why I stand with the Houston Five 21
- On campaign trail, Obama says GOP is... 15
- Gay marriage becomes legal in Arizona,... 14
- Expelled Nazis got millions in Social... 10
- Bishops scrap welcome to gays in sign... 9
- At rallies, Obama casts 2014 as key for... 8