[4] Cold River, Slow Start To Chinook Season

By April 13, fish counters at Bonneville Dam were still twiddling their thumbs, wondering where the great spring run of 2009 had got off to. This year's expected upriver run of around 300,000 chinook has fueled high expectations, but with only a little more than a thousand fish over the dam so far, fish managers were meeting to discuss possible changes to the fishing season--which is slated to end April 22 for recreational anglers.

They said daily counts should be "increasing dramatically" this week, based on timing curves from recent years. Flows have been increasing, and water temperatures as well, but water clarity was still high.

Commercial gillnetters had landed 3,300 chinook by the 13th and had released 784 unmarked ones (wild). That represents about half of the .378 percent allowable impact on the upriver stocks. They fished again last Wednesday, and an unofficial count had suggested they had landed another 1,200 chinook, about half what managers had expected.

Sportfishers have boated about 12,000 hatchery chinook so far, with a lot of time between fish. On April 4, nearly 3,300 recreational boats were counted in the lower Columbia, surpassing 2001's record count.

In 2001, by this time, nearly 135,000 chinook had been counted at Bonneville Dam, with 17,000 counted on the 13th alone. However, water temperatures were nearly 2 degrees C. warmer back then.

The University of Washington forecasters at Columbia Basin Research have estimated that only .5 percent of the run has passed Bonneville, with a peak arrival day of May 7, a week later than their preseason forecast.

Both tribal and non-tribal gillnetters have asked managers to shut down the sport fishery for a week to see if the run improves, but, so far, managers are sitting tight. They say a run update won't come until early May.

Some folks have suggested the California sea lions near Bonneville Dam have been keeping the fish from moving upriver, but there is no real data to suggest that may be the case. More than three dozen have been around the dam, of late, and 14 of them have been trapped. Seven have been euthanized, while four others have been shipped to aquariums around the country, and three released with acoustic transmitters.

Another novel hypothesis is that the chinook have such a sensitive sense of smell they can smell blood in the water and will not move upstream while the marine mammals are feasting away. Unfortunately, that theory doesn't explain why the springers eventually head upstream, sea lions or not.

In 2008, river conditions were similar. It was cold and the run was late. However, by this time last year, more than 7,000 fish had been counted at Bonneville Dam. By April 15, only 1,328 had been tallied.

However, the late start seems to be a continuing a trend that began in 2005, when only 453 fish had been counted by now. In 2006, only 182 had appeared and in 2007, 2,273 chinook had been counted at the dam.

Others have speculated that early inriver harvests since 2001, when spring sport and commercial harvest started again for the first time in many years, may have wiped out the early returning fish.

Cold water is still the prime suspect. Experts said it correlates quite highly with low adult numbers at the dam. -B. R.

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