A number of critically endangered fish have returned to the Sawtooth Range this year, with numbers at a way station along their journey at an eight-year high.
Eighteen of the rare fish had made it to the Sawtooth Valley so far this summer as of Friday, according to the Idaho Department of Fish and Game. Sockeye leave the ocean in the early summer, arrive in the Sawtooth Valley between late July and September, and spawn in Idaho in October.
At the Lower Granite Dam in eastern Washington, after which the fish have 450 miles of open water to swim through to get to the high-elevation valley, sockeye numbers are close to three times the 10-year average and are the third-highest since 1975, according to a news release.
So far, 2,072 sockeye salmon have passed the dam. In the Sawtooths, nine of these fish were trapped at Redfish Lake Creek, between Redfish Lake and Little Redfish Lake. The other nine were trapped at the Sawtooth Fish Hatchery, a mile upstream from the junction with Redfish Lake Creek on the main Salmon River, said Dan Baker, the hatchery manager at the Eagle Fish Hatchery.
The fish that are trapped in the Sawtooth Valley are trucked to the hatchery in Eagle, where some spawn in captivity while others are released back into lakes in the Sawtooths in September, where they spawn in the wild.
But fish returns remain vastly reduced, as more than a century of overfishing, habitat destruction, pollution and dams have imperiled the species.
Why have numbers ticked up?
“Ocean conditions have improved over the last couple years, which has improved ocean survival for Sockeye,” Baker said in an email. “The cool, wet spring has also benefited sockeye survival as the adults have been migrating upstream.”
As fish swim upstream, they can die from low water in the Snake and Salmon rivers and warm temperatures along the way, the release said. The numbers of fish that return each year can fluctuate a lot. In Idaho, fish are bred at hatcheries to try and sustain their populations.
A series of four dams were built along the lower Snake River between 1955 and 1975, after which Idaho sockeye were listed as endangered, in 1991. Between 1991 and 1999, only 23 fish returned to lakes in the Sawtooth Valley.
In the West, scientists say climate change is exacerbating drought conditions and warming stream temperatures.
Environmentalists and American Indian tribes in the Pacific Northwest have long pushed for breaching those dams, which produce electricity and allow for barge shipping, to save the fish.
In July, President Joe Biden’s administration released a report arguing that dam removal may be necessary. Washington Sen. Patty Murray and Gov. Jay Inslee, both Democrats, are working on a report on the topic to be released later this summer.
Idaho Republican Rep. Mike Simpson already supports a plan to breach the dams and replace their economic benefits. Idaho’s other Republican leaders in Congress and Gov. Brad Little are opposed to breaching the dams.