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Study: Pacific Salmon May be Able to Adaptby Jonathan SerrieFox News, November 1, 2000 |
Washington state has been grappling for years with the question of how to keep numbers of wild salmon from falling.
The government has halted construction projects, reduced logging and imposed restrictions on farmers in the name of protecting the endangered but tasty fish. Now, a study in the journal Science suggests salmon may be better at adapting to man's presence than experts once thought.
"Their age of maturity, the size of their eggs, the time when they breed those things evolve quite quickly," said University of Washington fisheries professor Thomas Quinn. "Quite quickly on the order of tens of generations rather than over thousands and thousands of years."
A University of Washington study examined a stock of sockeye salmon released into Seattle's Lake Washington and the nearby Cedar River around 1940. During the following 60 years a short time by biological standards the salmon in the lake and those in the river have evolved into two populations with unique genetic characteristics for survival in their very different habitats.
The researchers called the findings a sign of hope in a region that has been grappling for years with the question of how to keep wild salmon from disappearing. They say their study offers hope that salmon can rebound when man-made obstacles, such as dams blocking them from spawning areas, are removed.
Salmon from the Columbia River drainage in Washington state are among those hardest hit by dams, pollution and timbering operations. King salmon which historically returned to the river by the millions and supported a huge fishery have been depleted to the point of being listed as an endangered species.
Other Pacific salmons such as sockeyes from Oregon's (should read Idaho's) Snake River and Washington's Puget Sound have also been placed on the endangered list, with runs so small that their very survival is in question.
The Washington state government is still batting around ideas for a statewide plan to help wild salmon make a comeback. Draft versions of the plan which warn of more changes to hydroelectric dams, farming areas and fishing laws could sting in the form of higher electric bills, pricier crop-irrigation, reduced timber harvests and tighter limits on commercial fishing.
Some of the farmers, loggers and landowners who would suffer under proposed salmon-restoration efforts interpret the new study as evidence that drastic protection measures may be unnecessary.
"I also think it says before we go and we start tearing down dams and ruining people's lives and their jobs and regional economies that we need to find out more," said Russell Brooks of the Pacific Legal Foundation.
But researchers, although they agree more study is necessary, caution that just because salmon adapt well to the environment it doesn't necessarily mean that all is well. Some man-made changes to the rivers salmon call home have been so drastic that the fish haven't been able to adapt, the researchers said.
"People sometimes use this analogy," Quinn said. "Salmon are the canary in the mine shaft. When they start to go it means the air is foul. In fact, salmon are actually pretty tough. When you wipe salmon out, you really ruined things!"
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