Record chinook run, but coho, steelhead runs lag behind

The number of fall chinook passing Bonneville Dam continues to mount with nearly 1,000 more fish over the dam last week, increasing the record run to 954,376, or 212 percent of the 10-year average, according to NOAA Fisheries’ Paul Wagner at the November 18 Technical Management Team meeting.

The previous record of 953,222 fish set in 2013 was exceeded when the count went to 953,541 fish as of November 12, the most fish passing the dam since it was built 77 years ago.

Daily passage numbers are declining from 229 fish per day Saturday, to just 76 per day Wednesday last week (see http://www.fpc.org for fish passage details).

The coming years may not see the big runs of 2015, “so we could be in for a bad spell,” Wagner said. As indicators, he pointed to low spring chinook jack salmon counts over Bonneville Dam this year as well as the expectation that poor ocean conditions bode poorly for the juvenile salmon that migrated to the ocean this year. (The number of jacks in one year is an indicator of the size of the following year’s adult run.)

Spring chinook jacks over Bonneville this year amounted to just 13,314 fish, far below last year’s spring chinook jack run at 26,094, and under the 10-year average of 23,978.

On the other hand, it’s a mixed bag with the other runs of chinook salmon. The summer chinook jack count of 17,730 was about 10 percent below the 10-year average of 20,126 fish, and the fall chinook count at 82,476 was above the 10-year average of 77,225 fish.

Fall chinook passing over Lower Granite Dam on the Snake River has slowed to a near stop.

The total count of fall chinook at Lower Granite this year is 59,226 fish, the second largest run ever reported at the dam and also 212 percent of the 10-year average.

That’s a slight increase over the number at the dam November 12 when some 59,059 of the salmon had been counted at the dam during the late summer and fall.

The Bonneville Power Administration announced that a record 200,000 fall chinook were spawning at Hanford Reach upstream of McNary Dam and the last free flowing section of the Columbia River upstream of Bonneville Dam in the United States.

The estimated 2015 fall chinook run at the Columbia River mouth, however, still stands at 1,224,310 fish, the second largest run since the construction of Bonneville Dam and 132 percent of the pre-season forecast.

That’s just short of the record-breaking 2013 run of fall chinook (1,268,400) at the river’s mouth and slightly more than last year’s count (1,159,100).

Steelhead have not fared as well. Passage is below the 10-year average at both Bonneville and Lower Granite dams, Wagner said.

Some 266,855 steelhead had passed Bonneville June 1 through November 18, 76 percent of the 10-year average. Of those fish, 97,103 were wild steelhead. That’s 86 percent of the 10-year average. Passage has slowed to about 50 fish per day. About half are wild fish.

Some 136,863 steelhead have passed Lower Granite Dam June 1 through November 18, 81 percent of the 10-year average. Of those, 38,140 are wild fish. That’s 88 percent of the 10-year average, Wagner said. Several hundred steelhead are still passing the dam every day. Less than half are wild.

Coho salmon this year are performing poorly, Wagner said. Total passage at Bonneville as of November 18, was 36,845 coho. The 10-year average is 129,000 fish, so this year’s run is 28 percent of the 10-year average.

Chum salmon had began showing up to spawn downstream of Bonneville Dam. Biologists observed eight fish November 10 and more are expected. Some 167 chum have also passed the dam as of November 18.

The Corps of Engineers initiated chum operations at Bonneville Dam to provide good spawning conditions for the fish and allow access to Hamilton Creek by maintaining the dam’s tailwater at an elevation of 11.5 to 12.5 feet. The heavy rains last week briefly increased the tailwater elevation to 16 feet.