Monday, March 17, 2008

Chinook Salmon Fishery Collapse

Prized chinook salmon would be off-limits to fishing this year under a unprecedented proposal to halt all salmon fishing from Point Falcon in Oregon south to the Mexican border.

In the long term, the collapse of the salmon stock in the California rivers is a far graver threat to the world than the Bear Stearns (and the Bush economy) collapse. This year's Chinook salmon fishing season off the coasts of Oregon and California is likely to be cancelled, because the fish have disappeared. While no one is completely sure of the cause, the scientists who have been consulted believe changing ocean patterns, caused by global warming, are to blame.

NYTimes: Chinook Salmon Vanish Without a Trace

But federal and state fishery managers and biologists point to the highly unusual ocean conditions in 2005, which may have left the fingerling salmon with little or none of the rich nourishment provided by the normal upwelling currents near the shore.


Bill Petersen, an oceanographer with the National Oceanic and Atmospheric Administration’s research center in Newport, Ore., said other stocks of anadromous Pacific fish — those that migrate from freshwater to saltwater and back — had been anemic this year, seading him to suspect ocean changes.

After studying changes in the once-predictable pattern of the Northern Pacific climate, Mr. Petersen found that in 2005 the currents that rise from the deeper ocean, bringing with them nutrients like phytoplankton and krill, were out of sync. “Upwelling usually starts in April and goes until September,” he said. “In 2005, it didn’t start until July.”

Mr. Petersen’s hypothesis about the salmon is that “the fish that went to sea in 2005 died a few weeks after getting to the ocean” because there was nothing to eat. A couple of years earlier, when the oceans were in a cold-weather cycle, the opposite happened — the upwelling was very rich. The smolts of that year were later part of the largest run of fall Chinook ever recorded.

Yahoo News: Salmon fishing ban possible this year

In most years, about 90 percent of wild chinook or "king" salmon caught off the California coast originate in the Sacramento River and its tributaries.

Only about 90,000 adult salmon returned to the Sacramento River and its tributaries to spawn last year, the second lowest number on record and well below the government's conservation goals, according to federal fishery regulators. That's down from 277,000 in 2006 and a record high of 804,000 in 2002.

Biologists are predicting that this year's salmon returns could be even lower because the number of returning young male fish, known as "jacks," hit an all-time low last year. Only about 2,000 of them were recorded, which is far below the 40,000 counted in a typical year.

Other West Coast rivers also have seen declines in their salmon runs, though not as steep as California's Central Valley.

Experts are unclear about what caused California's collapse.

Some marine scientists say the salmon declines can be attributed in part to unusual weather patterns that have disrupted the marine food chain in the ocean along the Pacific Coast in recent years.

Dailykos: Don't Mess With Mother Nature

Back in the late 1960's it was possible to walk across the confluence of the Sacramento and American Rivers on the 14ft, open boats, each with 1 or 2 fishermen hauling in their limit of salmon swimming up stream to spawn. Freezers all over the Valley were filled with cleaned, dressed salmon that weighed 35 ot 40 lbs. each. By the mid 80's the size and the weight of the catch had decreased by half. Early in 2000 a salmon that weighed 15 lbs was cause for celebration.

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