Spring chinook run estimate is downsized once again

For the second time in two weeks, the estimated size of the Columbia River’s spring chinook run has been changed.

Just three weeks ago, the runs size forecast was downgraded by the U.S. v Oregon Technical Advisory Committee from its initial forecast of 160,800 fish to just 83,000. On May 30, the forecast was back up to 118,000 fish, according to an announcement by the U.S. v Oregon Technical Management Committee.

The 83,000 estimate was one of the 15 lowest returns on record, but most of those runs had been in the 1970's through the 1990's, according to Stuart Ellis, the TAC lead for 2017 and harvest management biologist with the Columbia River Inter-Tribal Fish Commission.

Since the run size update, recreational fishing for salmon and steelhead has come to a halt on the Columbia River. That could change, but the change is not likely initially to allow fishing for anglers in the river downstream of Bonneville Dam, according to Ron Roler, Columbia River fish manager for the Washington Department of Fish and Wildlife.

Based on the new run size update and an impact on threatened and endangered species of 1.7 percent, Roler said, the catch balance for non-treaty fishing – that’s both recreational and commercial fishing in the mainstem Columbia River – is 9,794 spring chinook. Some 8,000 fish had already been caught prior to shutting the fisheries down.

“There is some fish available for harvest, but there is still some uncertainty regarding the Snake River component of the run and especially the (Snake River) wild component,” Roler said. “The update on June 5 will be key in freeing up fisheries, but I don’t think anything will happen until the tribes resume their harvest and I will be pushing for this.

“If we are able to reopen fisheries, the first in line will be the mid-Columbia and the Snake River recreational fisheries. Their fisheries were curtailed before they even got started.”

At the time of the downgrade, Ellis said that the daily count of spring chinook over Bonneville Dam would need to be a little more than 1,300 through June 15 to even get the count to 75,000 fish. Since then, the passage of spring chinook increased to 3,000 to 4,000 per day, but after the Tuesday run size update, passage over Bonneville dropped again to 1,916 Tuesday and 1,311 Wednesday, May 31.

Total passage of spring chinook is now at 83,624 adults and 18,110 jacks as of May 31. Last year on May 31, 137,215 adults and 11,145 jacks had passed the dam. The 10-year average is 150,512 adults and 25,604 jacks.

Ellis also said this week that TAC “agreed to use a proportional adjustment based on relative pre-season forecast to update the Snake River natural origin run size to 11,100.” That’s 9.4 percent of the total number of fish over Bonneville Dam. However, “TAC reviewed some information that suggests that the Snake River natural origin run may be less than 9.4 percent of the Total Run. TAC will meet again on Monday June 5 and expects to provide additional run size updates.”

Paul Wagner of NOAA Fisheries at this Wednesday’s interagency Technical Management Team meeting called the sudden jump in chinook passage at the dam a “rally” and said “adult passage has come on strong in the past week and is now 55 percent of the 10-year average.”

“However, that’s not translating upriver just yet,” saying that passage at McNary Dam is just 38 percent of the 10-year average, Lower Granite on the lower Snake River is at just 17 percent of the 10-year average and on the upper Columbia River, passage at Priest Rapids Dam is 21 percent of average.

One improvement, he said, is the passage of chinook jacks at Bonneville, now at 86 percent of average. “So, there’s hope for next year, although that’s not a perfect indicator,” he said. One signal of the size of the following year’s adult run is thought to be the number of jacks returning during the current year.

Passage at McNary May 31 was 35,025 adults and 4,972 jacks. Last year the number was 77,764 adults (twice as many as this year) and 6,464 jacks. The 10-year average is 85,011 adults and 14,625 jacks.

Passage at Lower Granite May 31 was 9,767 adults and 2,073 jacks, far below last year’s count on the same day of 51,008 adults and 4,063 jacks. The 10-year average for that date is 48,905 adults and 8,509 jacks.

Passage at Priest Rapids Dam May 31 was 3,444 adults and 154 jacks. Last year was 12,160 adults and 706 jacks and the 10-year average is 14,096 adults, four times the current count, and 1,255 jacks.

However, even the small number of spring chinook in the Snake River have fisheries managers in Idaho cautiously optimistic that some recreational angling will be available soon. Angling for the fish had ended in Idaho May 24, except in Hells Canyon, due to the low number of chinook passing Bonneville, but since then the run has improved, an Idaho Department of Fish and Game news release says.

Low numbers of wild chinook may further constrain some fisheries as the number of Idaho wild chinook that have crossed Bonneville Dam is much lower than average. If those numbers don’t increase, fishing may be limited to areas where anglers are unlikely to hook wild chinook, such as the Little Salmon River. Areas typically open to fishing, like the main Salmon between Rice Creek and Vinegar Creek may remain closed, the news release said.