The Sept. 15 updated forecast for Hanford upriver fall chinook salmon, like in-season forecasts for points downriver, downsizes expectations but still includes a good number of fish.
The preseason forecast was for an adult return of 135,819 fall chinook to the mid-Columbia Reach. The Sept. 15 return prepared by the Washington Department of Fish and Wildlife’s Paul Hoffarth pegs the 2011 return to the reach at 58,478 adult chinook, considerably lower than predicted.
The Hanford Reach return includes both wild, naturally spawning salmon and fish produced at Priest Rapids Hatchery. They are part of “upriver bright’ fall chinook stock that includes returns to the Snake River and smaller components destined for the Deschutes and Yakima rivers. Snake River wild fall chinook are protected under the Endangered Species Act.
“It’s still a moderate run,” Hoffarth said of the anticipated return. A return equaling the Sept. 15 forecast would be more than twice the best return since he began producing forecasts for the Hanford Reach.
The return in 2007 “was horrendous” with only 12,000 adult fish, Hoffarth said. But the next two years were better at 22,000 in 2008 and 26,000 in 2009. The 2010 return, however was strong. A total of about 80,000 adults returned to the reach, and another 19,000 returned to the hatchery. The reach return included 6,600 jacks, 22,000 3-yar-olds and 32,900 4-year-olds.
The 2010 return boded well for the future, with those high numbers of 2-year-old jacks, 3-year-olds and 4-year-olds. Like most salmon return forecast methods, Hoffarth’s numbers rely on past returns to predict the future. As an example the broodmates of last year’s 2-, 3- and 4-year-olds should come back in strong numbers as 3-, 4- and 5-year-olds.
“We had three strong broods coming back” in 2010, Hoffarth said.
And strong counts and good fishing in the reach are proving the forecast to be correct. Already through Thursday 100,255 fall chinook have passed the mid-Columbia’s McNary Dam in southeast Washington. McNary ithe fourth and last hydro project the fish pass before the Columbia turns north and enters the Hanford. That only 88 percent of last year’s total through Sept. 22, but 116 percent of the 10-year average.
Fishery managers have a goal of assuring at least 60,000 fall chinook get past McNary to restock the hatchery, spawn in the wild and provide fisheries. The URB forecast for adults reaching the mouth of the Columbia is 323,400 adult fish. Sport and treaty and non-treaty commercial fisheries take a considerable toll downstream.
It’s also the last dam the fish pass before they enter the Hanford reach, and within a few miles of the Columbia’s confluence with Snake River. Through Wednesday a total of 22,122 fall chinook had turned right into the Snake and been counted at Ice Harbor Dam, the first dam upstream of the confluence.
Hoffarth said the dynamics have changed a bit in recent years with a larger return heading up the Snake River due to beefed up hatchery programs and an expanding population of natural spawners. Until recently about 50 percent, on average, of the fall chinook passing McNary were Hanford Reach fish, but that percentage has slipped to from 25 to 45 percent.
WDFW staff interviewed anglers on 353 boats last week in the Hanford Reach who had a total catch of 203 adult chinook, 33 jacks and 3 coho. Anglers averaged slightly better than a half a fish per boat. An estimated 845 adult chinook, 137 jacks, and 12 coho were harvested this past week.
Effort is spreading out throughout the Hanford Reach and the Tri-cities area, Hoffarth said. There were an estimated 3,408 angler trips taken this past week to the reach with more than 400 boats on the water each day on the weekend. For the season, 1,433 adult chinook, 249 jacks, and 12 coho have been harvested.