Spring chinook are finally starting to make a move, but it remains to be seen how strong this year's run will be.
The run languished below Bonneville Dam well past its normal timing and until two weeks ago was the lowest or latest ever recorded. But fish counts at Bonneville Dam started to pick up soon after.
As of Wednesday, more than 40,600 adult spring chinook had passed the dam on the Columbia River. That is well below the 10-year average of more than 96,000, but enough to give anglers and fisheries managers hope.
"We've had six days of really good counts now," said Chris Donley, fish program manager for the Washington Department of Fish and Wildlife at Spokane. "I think you can hear a collective sigh of relief from the fish managers."
Through Wednesday, 1,282 chinook had been counted at Ice Harbor Dam on the Snake River and 202 at Lower Granite Dam.
Donley said the run is more than two weeks late, and the situation is still dicey. But the run has shown enough that Washington's two-day-a-week seasons on the Snake River will continue this week.
"I expect a better number of fish will be in the Snake this next week, but it's still not going to be at the peak," he said.
Joe DuPont, regional fisheries manager for the Idaho Department of Fish and Game at Lewiston, said the latest projections show the run is likely to provide a harvest share of 1,400 adult chinook on the Clearwater River and its tributaries and about 400 on the Lower Salmon and Little Salmon rivers.
Those projections are based on what has been seen in previous years when the run has been late. But DuPont said it could turn out to be a conservative estimate if the run performs similar to last year's, which was extremely late.
He cautioned that high flows predicted on the Snake and Columbia rivers could stall the run and reduce survival of fish as they move between Bonneville and Lower Granite dams.
"There is a lot of things that are still unknown, but at this point it's looking much better than it was last week," DuPont said.
Based on detection of the tiny tags that are implanted in a percentage of hatchery fish, DuPont said about 6,300 chinook bound for the Clearwater basin already have passed Bonneville Dam. Only about 2,600 chinook bound for Rapid River Hatchery near Riggins have been detected there. Although that number is troubling, DuPont noted the tags did a poor job of representing the Rapid River run last year. Projections of the 2017 run size based on tag detections accounted for about 45 percent of the actual run strength. DuPont said fisheries officials are backstopping the tag-based run detections by taking genetic samples from a small percentage of fish at Lower Granite.
"About halfway through the run, we can look at genetics of fish trapped and get a lot better estimate," he said.
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