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Salmon Revival a False Alarmby the Editors ofThe Oregonian - November 27, 1999 |
Changes in ocean conditions may benefit wild salmon temporarily,
but the fish are still in trouble
Sometimes even good news can be misleading, and offer a false sense of security. An example was the prediction by state biologists earlier this week that 50,000 Snake River spring chinook will enter the Columbia River next year.
That this could be the largest run of Snake River chinook in the past 13 years is good news. It clearly shows that a dramatic shift in ocean conditions to a colder cycle has occurred. National Marine Fisheries Service biologists report that ocean temperatures and plankton counts show that a seven-year period of nutrient-poor seas has ended, at least temporarily.
This change helps young salmon as they grow into adulthood. The colder ocean water produces more nutrients for the small fish that salmon eat. That helps more salmon survive in the ocean, no matter how poor a jump start they receive as juveniles in fresh water.
However, this is no time to celebrate a heroic return to abundance. When these ocean conditions change again, replicating the poorer conditions of the past half-dozen years or so, the salmon will continue to decline unless Northwest policy-makers demonstrate the collective will to make major changes in the salmon's freshwater habitat.
State biologists also pointed out that the vast majority of the returning Snake River spring chinook next year will be hatchery fish -- about 45,000 of them. In the past, this would be considered very good news for fishermen because it predicates a strong fishery. But as scientists learn more about the adverse impacts of hatchery stock on wild fish survival, the news should raise worries about the ratio.
For example, this year only 4,600 Snake River hatchery spring chinook returned, compared with an estimated 2,700 wild Snake River spring chinook. If biologists are correct in their estimates, though, the hatchery fish next year will outnumber the wild fish by a ratio of 9-to-1. This means that wild fish will have a tougher time competing for food.
The estimates also illustrate vividly that when the wild spring chinook numbers plunge so low, as they did in the mid-1990s (only 745 fish made it to Idaho in 1995), the fish can't recover very quickly, even if the ocean habitat dramatically improves.
So why have hatchery fish fared so much better than their wild-fish cousins? Biologists believe that heavy spring runoffs in 1995 and 1996 helped, as did the changing ocean conditions.
But the main reason no doubt is that hatcheries turned out literally thousands of smolts -- which makes it possible for many to die without destroying the run.
So Nature has done us all a big favor, perhaps buying more time for the scientists and the politicians to figure out and then agree on a master plan to make changes in the salmon's freshwater habitat.
But there's a lot to be done. We should try to improve fish passage at the Columbia-Snake river dams, restore salmon habitat and spawning grounds, change the way we use hatcheries and continue to reduce harvests until the wild fish populations gain strength.
If the oceans are shifting to more nutrient-rich upwelling, salmon numbers should continue to improve. But unless we match those favorable changes with salmon-friendly actions in the Columbia River Basin, the imperiled wild fish still could die out forever.
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