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Run Down: Dams, Pollution Reduce West Coast Salmon Numbers

It is estimated that only 0.1 percent of the tens of millions of salmon that used to course rivers along the west coast before European settlement still exist



Dan Bennett, courtesy Flickr

Dear EarthTalk: What is the story with west coast salmon runs? I've heard conflicting reports in regard to whether the fish are abundant or going extinct.
—Rebecca Shur, Kirkland, Wash.

West coast salmon runs have been in decline for decades, stemming largely from the damming of rivers and the pollution throughout the fish’s extensive range from freshwater mountain streams to deep offshore ocean currents. Analysts estimate that only 0.1 percent of the tens of millions of salmon that used to darken rivers every summer and fall up and down the west coast before white settlement still exist.

Particularly worrisome is the accelerated downward trend in the last few years, signaling that some populations just may not be able to cope with fast-changing climatic conditions heaped on top of other existing pressures. But others suggest that the health of some of the region’s salmon populations—such as bountiful pink salmon off of Oregon and Washington and still thriving Alaskan runs—shows that with proper management we may be able to retain lively populations of both wild salmon and fishers.

Perhaps the hardest hit and most talked about salmon fishery in the world—California’s Sacramento River Chinook run—has been off-limits to fishers for two years now because of the low volume of wild fish returning to spawn. In 2008, only 66,000 Chinook salmon, a fraction of the former run, returned to spawn. While last year was slightly better, biologists warn that numbers are still too small to warrant reopening the fishery anytime soon. As to reasons for the decline, most analysts point to a range of factors including diversions of river water for farming, pollution, the intermingling of wild salmon with weaker, disease-ridden hatchery fish, and global warming—which creates some problems and exacerbates others.

Elsewhere the news is also bad. Sockeye salmon numbers in British Columbia’s Fraser River were at a 50 year low this past season, forcing closure for the third year in a row of what had been an abundant and reliable fishery. Canada’s Department of Fisheries and Oceans had predicted that some 10.5 million sockeye would return to spawn in the Fraser this past summer, but only 1.37 million made it back.

Glimmers of hope do exist. Salmon fisheries in Washington and many parts of Oregon had a big year in 2009. “Returns to the Columbia River, the region’s biggest salmon producer, were on the increase," reports Dennis Hull, an Oregon-based fishing guide and a contributor to Oregon Fishing News. “Coho returns in Oregon and points north were also on the upswing, allowing some commercial and recreational fishing off the coasts of Oregon and Washington.” The Oregon Department of Fish and Wildlife reports that 2009’s Columbia River Coho salmon run, numbering some 700,000 fish, was the biggest since 2001.

Groups such as Save Our Wild Salmon and the Klamath Forest Alliance are pushing policymakers to remove several large dams in the Columbia basin and elsewhere to spur wild salmon recovery. Other groups, such as Salmon-Safe and Stewardship Partners, are working with farms and other intensive users of the land to try to reduce pollution into salmon-rich watersheds. With 13 different salmon populations in the region already teetering on the brink, and the climate only getting hotter, time is surely of the essence.

CONTACTS: Canada’s Department of Fisheries and Oceans, www.dfo-mpo.gc.ca; Save Our Wild Salmon, www.wildsalmon.org; Klamath Forest Alliance, www.klamathforestalliance.org; Salmon-Safe, www.salmonsafe.org; Stewardship Partners, www.stewardshippartners.org.

EarthTalk is produced by E/The Environmental Magazine. SEND YOUR ENVIRONMENTAL QUESTIONS TO: EarthTalk, P.O. Box 5098, Westport, CT 06881; earthtalk@emagazine.com. Read past columns at: www.emagazine.com/earthtalk/archives.php. EarthTalk is now a book! Details and order information at: www.emagazine.com/earthtalkbook.

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