A persistent heat wave gripping parts of Washington state could spike temperatures as high as 105 degrees this week, prompting warnings from the National Weather Service to drink plenty of fluids, avoid the sun, and check up on relatives and neighbors.
There’s no mention of what to do, however, if you’re a salmon swimming upstream to spawn.
As air temperatures hit records in recent weeks, Native American and state fisheries experts and environmentalists are warning that water temperatures in the Columbia River Basin are similarly on the rise.
Those warming waters — in major tributaries like the Okanogan River and the Snake River — come at the same time as annual migrations of sockeye salmon from the Pacific Ocean, complicating a spawning ritual that spans hundreds of miles and is already peppered with human-made obstacles. Although salmon populations in the region have benefited from efforts to improve their spawning habitat, restore river flows and remove barriers from their travels, fisheries managers worry long periods of hot water could ruin it all in the years to come.
“Those water temperatures are warmer than ever this year,” said Tom Iverson, regional coordinator for the Yakama Nation Fisheries. “Literally, they’re almost too warm to swim in.”
That’s because the fish — including a record run of nearly 740,000 sockeye past the Bonneville Dam at border of Washington and Oregon as of Sunday, nearly 235 percent above the 10-year average — prefer a water temperature below 68 degrees.
The Okanogan River, which will be traversed by the majority of those fish during the final leg of their journey into British Columbia and a series of four chain lakes, has reached temperatures of nearly 83 degrees in recent days, according to U.S. Geological Survey data.
Reservoirs along the Lower Snake River, which are home to endangered Snake River sockeye, similarly crested to 69.53 degrees, according to the nonprofit Save Our Wild Salmon, which tracks water temperatures.
Now state and tribal officials are mulling over whether those fish — which enter the Columbia River Basin at the same location from the Pacific Ocean in Clatsop County, Oregon, and then split to their respective natal streams — could merit human intervention to help them make it to their destination.
Near-term efforts for the endangered Snake River population include trucking them upstream, while researchers ponder whether similar steps should be taken for more fish in the basin.
"Most salmon, when they hit fresh water, they stop feeding," Iverson explained, noting that the fish will rely solely on fat stores once they begin the journey and shift their focus to spawning.
"Once they start migrating, they basically have so many days to migrate. If the temperature is warmer they have fewer days," he added.
The Columbia River Basin's salmon and steelhead populations have been the focus of intensive restoration efforts for decades. Of the 16 stocks that historically spawned above the Bonneville Dam, four are extinct and seven are listed under the Endangered Species Act.
Anadromous fish populations — those whose lives begin in freshwater before swimming down to the Pacific Ocean and then returning to spawn — in the region once numbered in the millions, but were decimated as hydropower dams began to rise up on the river, beginning with the Bonneville Dam in 1938.
Construction of the dams and the impacts on salmon and steelhead populations "disproportionately harmed" eight tribal nations — the Nez Perce, Yakama, Warm Springs, Umatilla, Coeur d’Alene Tribe of Indians, the Confederated Tribes of the Colville Reservation, Shoshone-Bannock Tribes of the Fort Hall Reservation and the Spokane Tribe of Indians — the Biden administration acknowledged in a report issued last month.
Efforts to restore the populations — including regional and federal programs to raise fish in hatcheries — have totaled at least $20 billion since 1992, according to the Idaho Conservation League.
But despite that enormous investment, salmon and steelhead have continued to struggle. Critics, too, say the focus on salmon breeding in hatcheries along the rivers in the basin has resulted in farmed fish having “genetic and ecological interactions” with wild fish, putting the species further at risk.
Restoration efforts also failed to curb legal battles over hydropower operations on the Snake and Columbia rivers, although one major lawsuit is on hiatus while the Biden administration seeks to implement a $1 billion settlement agreement.
In the meantime, fisheries managers, tribal leaders, state officials and environmentalists are cheering the unexpectedly large run of sockeye this month.
"We're in the middle of a record sockeye migration with respect to the Columbia River population of sockeye," said Miles Johnson, legal director at Columbia Riverkeeper. "That's a huge recovery story.”
The sockeye resurgence is of wild fish, separate from hatchery breeding, Johnson said. "It's a testament to what these fish are capable of when we give them a chance,” he added.
Chad Jackson, a fish program manager in the Washington Department of Fish and Wildlife, described the event as a “bit of a perfect storm,” attributing the large number of fish to a successful outward bound migration and survival rates in the ocean.
Too hot to move
That success, however, must still survive the unusually warm temperatures in the Columbia River Basin’s tributaries.
The problem is what scientists call a “thermal barrier,” which marks the point at which the water temperature becomes too warm for the fish to continue their journey — typically over 68 degrees during both day and night.
It’s found where the Columbia River meets the Okanogan River, which travels north into Canada and is reliant on snowpack and prone to low flows and high temperatures. The salmon will typically halt their upstream travels at this point in Brewster, Washington, while waiting for the water temperature to drop back to an acceptable level allowing them to move on.
Biologists in the region warn the thermal barrier — which occurs annually — is starting earlier and expected to last longer than usual.
“A lot of people who are in salmon management restoration, we worry about this thermal barrier becoming much longer in duration and intensity,” said Jackson, with the Washington wildlife agency.
Jackson said there are no plans in place to relocate the salmon. But the possibility of such action in future years — with climate change driving protracted summer heat waves — is a key discussion for the state and other fisheries managers, he noted.
"If conditions become worse, how can we get sockeye up into Canada during those years, and how can we predict when that action is necessary?" said Jackson, whose work is focused on sockeye salmon bound for the Upper Columbia River above the Priest Rapids Dam in Mattawa, Washington. That dam is about 160 miles due south of the Canadian Border.
Sockeye salmon making their way up the Columbia River to Canada begin to arrive in Washington state in late June, with the migration in full swing by the end of July.
"They only have so much energy to make it up there," Jackson said. "The worry about the thermal barrier being prolonged later into the fall is that their success of being able to make it [to the spawning grounds] diminishes."
Michael Milstein, a spokesperson for NOAA Fisheries West Coast Region, said the agency is concerned about potential fish losses depending on how long the thermal barrier remains in place but remains hopeful about the outcome.
"The bottom line, we shouldn't lose sight of the fact that this is a success story. We're seeing so many salmon come back given all the risks and threats that they face. It does show that people working together and using good science can figure out what the fish need and give it to them," Milstein said.
He added: "We can't always control the climate but we can make the best possible decisions."
Hitching a ride?
Although temperatures in portions of the Columbia River Basin have spiked in previous years — an early heat wave in 2015 trapped fish in the Lower Columbia River, resulting in a major die-off, and temperatures in 2021 achieved levels similar to this season — salmon populations have never been physically relocated across the thermal barrier at the Okanogan River.
"People are asking the question, people are thinking about it, but logistically there are a lot of steps and a lot of things to contend with," Jackson said. "It's not as simple as — pull some fish out of the river and truck them into Canada."
The majority of these sockeye salmon in the Columbia River will ultimately end up in British Columbia, in the Osoyoos Lake, Vaseux Lake, Skaha Lake or Okanagan Lake.
"Sockeye can be pretty delicate and sensitive to stressful events, more so than other species of salmon," Jackson added. In addition to any permitting issues between the United States and Canada, he pointed to concerns over how and where to safely collect fish into hatchery trucks, and then keeping the water properly cool over the long journey.
"I think people are asking the question," Jackson said, "and trying to plan ahead."
That includes the Confederated Tribes of the Colville Reservation, which is working with the Okanagan Nation Alliance in Canada, and the provincial government on how water flows in the region could be moderated to assist fish once the thermal-barrier breaks.
"We're trying to minimize any mortality associated with migration," said Chris Fisher, principal biologist at the Colville Tribes Fish and Wildlife Department.
Fisher's agency is weighing whether water could be released from the Zosel Dam, managed by the Washington State Department of Ecology, increasing flows to ease passage of the fish once the migration begins up the Okanogan River.
Typically, it takes the fish about two days to travel the 60 miles upstream, but researchers want to ensure that the fish do not become trapped — should water temperatures drop and then rise back up during daytime highs — during that journey.
"Let's try to facilitate when the thermal barrier breaks, as much unimpeded access as we can," said Fisher. "It's better than just watching. We have to try something."
Lower Snake River plans
In the Lower Snake River, however, efforts have already begun to transplant sockeye into the cooler reaches upstream.
The Snake River is home to an endangered sockeye — the population of a few thousand is largely made up of hatchery-born fish — which veers off from its more popular relative, the sockeye populations headed to British Columbia — after entering the Columbia River.
Iverson, with the Yakama Nation Fisheries, confirmed that sockeye are being trapped at the Lower Granite Dam and then being moved by truck to an Idaho state-run Eagle Fish Hatchery.
The effort aims to collect about 50 fish each day, with a goal of a few hundred fish captured during the spawning season.
While the main stem of the Columbia River is typically fairly cool, Iverson said sockeye that veer into the Snake River face higher temperatures.
Fisheries managers can attempt to use water from the Dworshak Dam in Idaho to moderate temperatures.
“At the Clear Water River and the Snake River confluence, we try to mix water and create a water recipe that keeps temperatures down around 68," Iverson explained. "It's more art than science."
But when temperatures in the reservoirs lining the Lower Snake River become too high for the fish, human intervention is required, Iverson said.
Given the dwindling numbers of Snake River sockeye, "every one of those fish counts."
The series of four dams along the river is at the heart of a dispute over how to balance the future success of salmon and steelhead populations with the current hydropower production, transportation and irrigation needs of the region.
As part of the $1 billion settlement the Biden administration struck late last year in a long-running lawsuit over hydropower operations on the Snake and Columbia rivers, various federal agencies are examining how the benefits of those dams might be replaced if the structures are breached. Only Congress has the authority to call for the dams’ removal, however, and Republican lawmakers in the region have voiced strong opposition to the effort.
"We think with the removal of those dams we'd have much more favorable temperatures," Iverson said. He noted that a naturally flowing river would also create "deep pools and hideouts for the fish" to act as sanctuaries when temperatures rise.
"The heat's not new. It is getting hotter," Iverson said. "They have mechanisms to deal with that in a natural environment."
