Spring chinook run downgraded to half of early prediction

The regional advisory committee that forecasts Columbia River salmon runs so fisheries managers can set recreational, commercial and tribal fisheries last week cut their early season run size prediction for spring chinook in half.

Recreational fishing for salmon and steelhead has come to a halt on the Columbia River, and the new forecast assures that angling will not be resumed until June 15, the cutoff date distinguishing the spring and summer runs of chinook, unless more fish begin to move over Bonneville Dam, which could prompt a revised and perhaps higher run forecast.

At its meeting May 15, the U.S. v Oregon Technical Advisory Committee (TAC) reviewed the spring chinook run size which it had earlier predicted at 160,800 fish, cutting its estimate nearly in half to 83,000 fish.

In a statement released that afternoon, TAC said that it “examined a number of different possible predictors and agreed to a model that predicts a total Bonneville passage through June 15 of 75,000. This model had a 95 percent prediction interval of 43,000 to 107,000; characterizing the range of possible outcomes. Current estimates of total fishery mortality and research fishing mortality on upriver fish in the Lower Columbia River total 8,000 which makes the current river mouth run size projection for upriver spring and Snake River spring/summer Chinook 83,000. TAC will meet again on Monday May 22 and will provide additional run updates.”

TAC typically reviews its early season run size halfway through the run. On average, half the run passes Bonneville by May 7. But when it met May 1 and again May 8, it said that there was still insufficient data to provide an accurate run size update.

Still, 2017’s 83,000 spring chinook forecast is not the worst run on record. Stuart Ellis, the TAC lead for 2017 and harvest management biologist with the Columbia River Inter-Tribal Fish Commission, said that there have been 14 years with lower river mouth run sizes since Bonneville Dam was built – all in the 1970's through the 1990s.

“We need average daily counts of a bit over 1,300 per day between now and June 15 to get us to 75K at Bonneville,” he said. “So this run could still be higher than we are predicting if the counts are good. It could go the other way too.”

As of May 17, 37,899 spring chinook adults and 3,108 spring chinook jacks had passed the dam, and current passage is running around 2,000 per day (2,204 Monday, 2,201 Tuesday and 1,900 Wednesday). Last year on May 17, 114,671 adults and 8,049 jacks had passed the dam. The 10-year average is 129,528 adults and 18,191 jacks.

The dismal returns and TAC’s revised run size forecast prompted the Washington Department of Fish and Wildlife to close spring chinook fishing immediately in the lower Snake River (https://fortress.wa.gov/dfw/erules/efishrules/erule.jsp?id=1971). Recreational fishing for spring chinook had already closed in the Columbia River downstream of Bonneville Dam April 23 and it closed upstream of the dam May 5.

Fishery managers had earlier postponed the annual fishery for hatchery steelhead and jack chinook salmon from Tongue Point upriver to the Interstate 5 Bridge, which was set to begin this week. Although steelhead anglers would have been required to release any adult salmon they caught in the postponed fishery, a certain percentage would die after release.

“There is no room for any non-treaty fishery, in fact the Snake River recreational fishery was just closed and we are working on closing or reducing the fishing area in the SAFE commercial fisheries to eliminate risk of impacting any up river chinook,” Ron Roler, Columbia River fish manager for the Washington Department of Fish and Wildlife, said this week. “TAC reduced the run size to 83,000 upriver Chinook and they reduced the Snake River wild component, which further restricts fisheries.

“I do believe that the high flows have reduced passage at Bonneville Dam. Spring chinook do not begin spawning until late summer and are in no hurry to fight past the high water. Flows are not projected to drop in the near future, so I am hoping that a change in weather might trigger movement past the dam. Until they move, we are managing on a reduced run size and management means watching the dam count and hoping they move sooner than later.”

Only the tribal fishery remains open, which has about 1,000 more fish to catch, according to Ellis. He added that tribal subsistence fishing is still open in Zone 6 and that the “tribes are watching the fishery carefully as any future run size changes could still affect the number of fish available for harvest.”