Tests confirm return of middle Deschutes sockeye salmon
The Confederated Tribes of the Warm Springs Reservation of Oregon and Portland General Electric released laboratory results of genetic tests Tuesday, confirming that last summer’s adult sockeye salmon returns at the Pelton Round Butte Hydroelectric Project were native to the middle Deschutes basin.
A total of 536 sockeye returned to the project during the 2016 run, exceeding returns that had ranged from 19 to 86 fish in the years since a pioneering effort to reestablish the run began in 2010.
“These are exciting results,” said Brad Houslet, CTWS’ fisheries manager. “We were confident that this summer’s sockeye were Lake Billy Chinook fish, which is why we passed a portion of them back upstream to spawn in the Metolius basin, and the genetic testing reaffirms this run was a clear result of our reintroduction program.”
As co-owners of the hydro project, PGE and the Tribes are working collaboratively with an extensive partnership of state, federal and local agencies and conservation organizations to restore wild salmon, steelhead and lamprey runs that were cut off when the dams for the project were built on the Deschutes River in the 1950s and 1960s.
In 2010, the Pelton Round Butte co-owners began operating a new fish passage system that allows juvenile salmon and steelhead to migrate downstream, past the dams. The sockeye that returned last summer were based on an existing kokanee — land-locked sockeye — population in Lake Billy Chinook.
“The large number of adult sockeye passed back upstream into Lake Billy Chinook this past summer and fall gave us opportunities to observe these fish first-hand on their spawning grounds in the Metolius River and tributaries,” said Megan Hill, PGE’s fisheries and water quality manager,
“It was so exciting to see this large salmon, with the red body and green head, spawning next to the much smaller kokanee — something that hadn’t been seen in the basin for decades.”
Of the 536 adult sockeye that returned to the Pelton Round Butte Project in 2016, eight had external marks used by fisheries biologists to identify them as stray fish from other river basins. Most of the remaining fish had no identifying marks, so a fin clip was taken to confirm their origin using genetic analysis.
The testing was performed by the Hagerman Genetics Laboratory, a research center operated by the Columbia River Intertribal Fish Commission and the University of Idaho.
The results gathered and analyzed this fall show that over 93 percent of the returning sockeye originated in the middle Deschutes basin. The majority, 92 percent, were from Lake Billy Chinook.
Based on physical characteristics of the fish, the Oregon Department of Fish and Wildlife and CTWS authorized PGE to pass 463 of the returning sockeye upstream of the hydro project during the summer and early fall of 2016 to complete their life cycle and spawn in the Metolius basin. The remaining 73 sockeye were retained at ODFW’s Round Butte Fish Hatchery to spawn.
PGE, CTWS and ODFW then conducted regular spawner counts in the basin to identify spawning sockeye and kokanee. Sockeye were observed on the spawning grounds throughout the Metolius River basin — with sightings in the mainstem Metolius River near Camp Sherman as well as tributaries of the Metolius including Abbot Creek, Jefferson Creek, Spring Creek, and Heising Springs.
In addition to the ongoing work of reestablishing the sockeye run, spring Chinook and steelhead have also been passed upstream of the project each year since 2012, when the first adult fish that had completed their round trip from the middle Deschutes basin to the ocean began returning.
Over 1,200 adults have been released to complete their lifecycle and further the long term goal of restoring sustainable, harvestable salmon and steelhead runs, improving habitat and enhancing water quality in the Deschutes.
In-stream video of one of the returning sockeye is available online at https://youtu.be/CkwXuRT4fUk
