SEATTLE — Earlier this summer, the record return of sockeye salmon on the Columbia River looked to be doomed by water too warm to pass. But the run got a well-timed break from the heat.
The Fish Passage Center recorded an astonishing 755,909 sockeye over Bonneville Dam this year, smashing the 10-year average return of 329,570. About three-quarters of those fish were headed to their Canadian spawning grounds via the Okanogan River.
The huge success of this year’s run was helped by better management by dam operators of water conditions in the Columbia on both sides of the U.S.-Canada border. It helped a boomlet of baby sockeye make it to the sea, where improved ocean conditions also contributed. Implementation of a fish water management tool since 2014 has been key in turning this run of salmon around from near extinction in 1994 to one of the strongest in the Columbia Basin — despite crossing nine dams.
A break from summer heat
All that good news was turning dire earlier this summer, when an unusually early and punishing heat wave in July sent temperatures to 80 degrees in the Okanogan. That set up what biologists call a thermal barrier because hot water is a stopper, real as a wall, to a cold water fish such as salmon. Sockeye staged in the Columbia, refusing to enter the Okanogan to get to their spawning grounds across the border.
Managers worried the record run would cook in the Columbia before ever reaching the spawning grounds. That has happened before. In 2015, when not only the Okanogan, but the entire lower Columbia, heated up.
“Back in early July, we were extremely worried we would have a similar outcome to 2015,” said Cody Desautel, executive director for the Confederated Tribes of the Colville Reservation. Fortunately, temperatures in the Columbia stayed about 1.5 degrees cooler than average. Fish had a safe place to wait — and the weather broke. When cooler temperatures and some rain finally arrived, fish made a run for it.
A torrent of sockeye — about 362,452 fish — made it home, as water temperatures in the Okanogan dropped from around 73.4 degrees on Aug. 18 to 66.2 degrees by late August.
Relieved as they are, fish managers know on both sides of the border the thermal barrier will set up again. “It absolutely will happen again, and it will happen more frequently,” Desautel said. These fish are adapted to manage it — to a point, Desautel said. But climate change is pushing them beyond what they can survive.
A sockeye salmon mitigation strategy has been in planning stages for three years, noted Tyson Marsel, hatchery biologist with Okanagan Nation Alliance Fisheries.
The goal this year was to test a strategy with a collaboration of fish and dam managers to transport live adult salmon across the U.S.-Canada border — a first. Managers planned to capture fish at Wells Dam and transport them by truck to Canada, with a test run of between 25 and 200 sockeye.
By the time permitting was finalized, however, there weren’t enough adult sockeye making it to the Wells Dam fish ladder to give it a try, Marsel said. Nonetheless, the team completed all the necessary preparations, including securing the trucks, trapping fish and the necessary veterinary inspections.
“These efforts will hopefully streamline the permitting process in future years, allowing for timely fish capture when the mitigation strategy is critically needed,” Marsel said in an email.
Longer term, Colville and other tribes are working to reestablish salmon populations in the upper Columbia watershed, above Grand Coulee and Chief Joseph dams, to give fish access to cold water habitat that will be essential in a warming world.
Salmon have been entirely blocked from the upper watershed since construction of Grand Coulee, completed in 1942, cut off 745 miles of the upper river habitat (as well as many tributaries). Reintroducing salmon to the upper watershed is a top priority of tribes in the blocked territories on both sides of the border for ecosystem, cultural and economic benefits.
Once the greatest salmon-producing river on Earth, the Columbia today produces remnants — more than 1 million salmon in a good year — when 10 million to 16 million used to routinely come home, feeding everything from orcas in the sea to wildlife all along the rivers, the soils and trees, and of course, the people.
As part of the ongoing reintroduction plan, this year’s big sockeye run enabled the Colville, Spokane and Coeur d’Alene tribes to move about 309 sockeye and 1,453 Chinook above Grand Coulee and Chief Joseph Dams as of Aug. 22, Desautel said.
Those fish will be tracked to determine their success recolonizing their home waters. Reintroduction is being pursued in four phases of research and evaluation.
Funding for the effort is being provided in part by a settlement agreement in September 2023 that secured $200 million from the Bonneville Power Administration, a federal agency that markets power from the dams, to be paid over 20 years to advance the tribally led implementation plan to restore salmon and steelhead to the Upper Columbia Basin.
