Adult salmon and steelhead, with a little boost from their human friends, may spawn this year in the upper Deschutes, Metolius and Crooked river basins for the first time in more than 50 years.
The Oregon Department of Fish and Wildlife on Thursday announced agreement on a one-year strategy amongst involved state, federal and tribal parties to give returning spawners a lift over what has for the past half century been a three-dam dead end.
Fishery managers from ODFW, the Confederated Tribes of the Warm Springs Reservation, and Portland General Electric plan to trap returning spring chinook and sockeye salmon and steelhead below the Pelton-Round Butte complex of dams in central Oregon, haul them aboard trucks and release them above Round Butte Dam in Lake Billy Chinook.
From there it is hoped the fish will find spawning grounds in one of the three rivers and produce a new generation – the first generation to be produced above the dams in those more than 50 years. The Crook, Deschutes and Metolius join above the dams to become the Deschutes, which then flows 100 miles from the lowermost dam into the Columbia River.
The anticipated return of adult summer steelhead and sockeye and chinook salmon to these basins would be a major milestone in an ambitious fish reintroduction effort aimed at re-establishing anadromous fish populations that were cut off by the construction of the Pelton Round Butte Dam complex on the Deschutes River in the early 1960s.
The planned spawner trapping effort later this year will take aim at “known origin” fish – for chinook and steelhead that means fish that were outplanted as juveniles in the tributaries above the dam who later found their way down through the reservoir to a new fish collection device, which was first fully operational in 2010, at Round Butte.
Collected fish, including kokanee-turned-sockeye seeking a path to the ocean, were then transported around the dams and released downriver so they could continue their journey to the ocean. The drainage was once one of only two Oregon sources of sockeye, but those fish became a land-locked version of the species – kokanee – after the dams were built. One of the aims of the reintroduction effort is to rekindle a sockeye run.
A total of 44,000 spring chinook, 7,700 steelhead, and 49,700 kokanee were passed downriver in 2010. And they are expected to produce the first significant number of adult fish to return to the dam complex this summer and fall.
Last year seven spring chinook from above the dam returned. They were the product of a tributary trap and haul operation that send 666 smolts downstream in 2009 before the collection facility was working. A total of 19 “one-salt” sockeye also returned from the 2010 outmigration.
“To date, a total of 39 1-salt steelhead have been captured and transported to the RBH [Round Butte Hatchery] for spawning,” according to the Feb. 23 “2012 Pelton Round Butte Adult Passage Strategy.” The document notes that recent smolt-to-adult returns for Round Butte Hatchery steelhead (including fish that have spent one year in the ocean and two-salts) has averaged about 3 percent.
“Applying that SAR to the smolt outmigration from 2010 (7,733) the expected 2012 return of adults would be approximately 232 fish,” the passage document says.
“We’re just keeping our fingers crossed,” said Don Ratliff, PGE senior biologist. “We’re hoping we have several hundred” fish of known, upstream origin to return.
The projected return of upstream origin spring chinook is 400 fish, a number based on the recent average SAR of Round Butte Hatchery fish. The sockeye are a wild card, since there are no recent returns on which to base an estimate.
According to Mike Gauvin, ODFW Pelton Round Butte mitigation coordinator, approximately half of the expected returning adults will be released into Lake Billy Chinook to continue their upstream migration. Many of these fish will be fitted with radio tags so biologists can study their migration behavior and spawning locations.
The other half of the fish will be taken to the Round Butte Hatchery and used as broodstock to produce young fish for release into upstream habitats in 2013. Round Butte Hatchery, located at the dam is owned by PGE and is operated and managed by ODFW. It produces spring chinook and steelhead primarily for downstream harvest. It has now added sockeye to its repertoire.
The expectation is that the upstream origin spring chinook, along with their hatchery kin, will begin trickling in in early May with the tail end of the run stretching to late July. The sockeye return timeframe is estimated to be June-September. Steelhead arrivals generally stretch from Oct. 1 through March 1.
The returning fish are collected at the Pelton adult trap at the reregulating dam near river mile 100. The reregulating dam was built to even out flows from the two upstream hydro projects, Pelton and Round Butte.
“While we have developed a strategy for 2012, it’s been difficult to come up with a long-term approach because there are still so many unknowns,” Gauvin said. “Having this interim strategy will give us an additional year to better understand the behavior and migration of returning fish before we develop a multi-year proposal.”
“The whole process here is based on adaptive management,” Gauvin said.
“Due to the high degree of uncertainty associated with the magnitude of the run size and age class structure of the 2012 returns, the Co-managers will limit decision making to 2012,” according to the new passage document. “At the conclusion of the 2012-2013 adult spawning season we will meet with the Fish Committee to evaluate results and develop recommendations for the following two years, after which the program will be assessed and future direction will be determined.”
The fish passage strategy was developed in conjunction with the Pelton Round Butte Fish Committee, which includes representatives from the U.S. Fish and Wildlife Service, National Marine Fisheries Service, U.S. Forest Service, Bureau of Land Management, Bureau of Indian Affairs, PGE, ODFW and non-governmental organizations.
The adult salmon and steelhead returning to the dam this year were released as young fish into upstream habitats beginning in 2007 as a part of the reintroduction program. The reintroduction program is part of the federal licensing agreement for the dams. PGE and the Warm Springs tribes, co-owners of the Pelton Round Butte Hydroelectric Project, constructed and began operating a fish collection facility at Round Butte Dam in 2009 to capture the outmigrating smolts and release them below the dam so they could continue their migration to the ocean.
For more information go to http://www.deschutespassage.com/index.html
And see CBB, June 3, 2011, “First Two Spring Chinook Return As Part Of Effort To Return Salmon Runs To Upper Deschutes Basin” http://www.cbbulletin.com/409532.aspx