Daily spring Chinook at Bonneville picks up, but still far below 10-year average

Published 11:29 am Tuesday, May 8, 2018

Passage of spring Chinook salmon at Bonneville Dam was at just 996 fish as of April 25. That is the lowest number of fish passing the dam on that date since 1980, according to an Oregon/Washington joint staff report released April 26.

However, the passage number rose quickly to 10,570 fish by May 3. That’s still nearly seven times lower than the 10-year average of 72,274 on that date, but twice last year’s passage of 5,192 fish.

Day by day from April 25 when 181 fish passed the dam, daily counts rose. April 26, some 283 fish passed, with 804 passing April 27, 1,357 April 28, 1,812 April 29, 1,002 April 30, dropping to 633 May 1, 978 May 2 and a big daily jump to 2,705 May 3.

“Last year was late, but hopefully this year is late too,” said NOAA’s Paul Wagner at this week’s interagency Technical Management Team meeting.

The preseason forecasted run of upriver spring Chinook is 166,400 fish. On average half of the run passes the dam by May 8. The US v Oregon Technical Advisory Committee is expected to update the run size in the next couple of weeks. The first update had typically occurred between April 29 (2015) and May 15 (2017).

“We met and discussed the run, but we all thought it was still too early to try and update it,” said Columbia River Inter-Tribal Fish Commission’s Stuart Ellis and TAC lead this year. “We will meet again at least each Monday and review things. It’s possible we could meet at other times also depending on the needs of the fishery managers.”

Over the past ten years, adult runs have averaged around 204,600 (range 115,800 to 315,300), according to the Compact’s Winter Fact Sheet #3.

The preseason forecasted run for upriver spring Chinook in 2017 was 160,400, but as has been noted, that run was late to arrive and by June 15 when the spring Chinook run becomes the summer run, the upriver run had totaled just 115,821 fish.

With the 5 year average (2013 – 17) at 28,875 spring Chinook on April 25 and the 10-year average of 29,538 fish, some 13 percent of the run typically passes the dam on this date, the joint staff report says.

The winter season Select Area commercial fishery concluded April 17. Landings in that fishery total 1,110 Chinook, including about 90 upriver fish. The spring season opener occurred on April 19 with approximately 257 Chinook landed, including 36 upriver fish.

No mainstem commercial fishery in the Lower Columbia River is currently planned for 2018, the report said.