Sockeye Reintroduction VI

Under this project, around 10,000 sockeye broodstock was collected and relocated to Lake Cle Elum. The YN participated in a feasibility study to test Whoosh Technologies Fish Passage utilizing a portion of the sockeye collected for the Reintroduction Project. All sockeye used in this study were transported from Priest Rapids Dam directly to Roza Dam where radio tags and pit tags were inserted. The sockeye, were divided evenly into a control group that was placed directly into the Lake and the Whoosh Group that was taken to the base of Cle Elum Dam to be placed in the Fish Cannon to be sent over the dam. Results have yet to be determined.

Yakama Nation staff presented information on this project at the Annual Bilateral Okanagan Basin Technical Working Group Meeting (BOBTWG) in March 2017 at Penticton Lakeside Resort and Convention Centre and at the
2017 Annual General Meeting of the Oregon chapter of the American Fisheries Society which was held in Bend OR. The YN presentation was accompanied/followed by Andrew Matala Geneticists from the CRITFC Hagerman Laboratories in Hagerman Idaho with his findings on the Sockeye genetic sampling done during the reintroduction. Yakama staff also assisted Bureau of Reclamation during Cle Elum Dam tours and sockeye spawning tours above Lake Cle Elum over the years.

YN staff also estimated sockeye populations—fry to smolt survival and smolt output—using Hydro Acoustic survey. They conducted field surveys in the Cle Elum Lake watershed to form a baseline data starting point (chemical limnology, physical limnology, stream surveys, invertebrates, thermographs, bathymetry, ect.) as they continued with the reintroduction efforts. In 2015-16, YN started its own Lake Study on all the Lakes in the Yakima Basin.

In addition to the trap estimates Hydro-acoustic work, results will be used to try and determine overall parr production within Cle Elum Lake. This data will give an understanding of egg-parr survival. As the number of adults placed in the lake is a known and the average fecundity is also known by using the hydro-acoustic readings, an estimate of the number of parr present in the lake will be determined. This information will be used to determine overall smolt production from the lake.

Now that the pathway to permanent sockeye passage is progressing, the co-managers feel that to succeed with reintroduction of formerly native anadromous species, such as sockeye and spring Chinook salmon, as well as increasing existing resident native populations, such as burbot and cutthroat trout, something needs to be done to control or preferably eliminate Mackinaw (lake trout; Salvelinus namaycush), a non-native apex predator which was introduced by Kittitas County in 1920. So YN and WDFW continued their aggressive Mackinaw removal in the Cle Elum Reservoir. Six 100’ x 20’ corked and non-corked gillnets, one with 4” mesh and one with 3”, were lowered to the bottom and set from shore. YN also included three 200 x 20 corked diver small mesh 1, 2, and 3 nets at the bottom of the lake to net juvenile mackinaw in November and December 2017. The netting strategy was refined over the time so that it maximizes lake trout catch rates while minimizing incidental by-catch of rainbow trout, cutthroat trout, burbot, spring chinook and sockeye.

During the fall and winter months spawning adults and some juvenile lake trout on the northwest end of the lake near a slide area that was a preferred spawning area were targeted. All non-target fish were returned to the lake unharmed when possible. Once a large or significant numbers of non-target fish were captured in the set area, the nets was pulled and reset at another location.

The benefit of this project is to reintroduce sockeye back into its historical areas within the Yakima River Basin starting first with Lake Cle Elum. The YN views this project as not only returning sockeye to its historical range, but also as a major part of rebuilding the ecosystem as a whole. In addition to enhancing the diversity, spatial distribution, and resiliency of the aggregate Columbia River sockeye stock, this reintroduction restores the well-described and broad benefits of marine-derived nutrients to a myriad of aquatic and terrestrial species in the upper Yakima watershed, including ESA-listed bull trout and summer steelhead. Removing introduced Mackinaw from the lake is also a critical part of restoring a self-sustaining sockeye population and natural ecosystem function.

Four natural glacial lakes in the Yakima River Basin supported sockeye salmon historically, but the salmon were extirpated in the early 1900s when timber crib dams were constructed at the outlets of the lakes. Cle Elum Lake was first dammed in 1906. In 1933, the contemporary Cle Elum Dam was constructed to increase the water storage capacity for irrigation. Currently there are three stocks or evolutionarily significant units (ESUs) of sockeye salmon in the interior Columbia River basin: Lake Wenatchee ESU (Washington), Okanogan River ESU (Washington), and the Snake River ESU (Idaho). The Snake River sockeye salmon ESU was listed under the ESA on November 20, 1991. A subsequent final listing determination issued by NOAA-Fisheries on June 28, 2005 reconfirmed the endangered status of the Snake River sockeye salmon ESU, which primarily occurs in the upper Salmon River basin in Redfish Lake. The Lake Wenatchee and Okanogan River sockeye salmon ESUs in central Washington State were found to be not warranted for listing under the ESA, and are therefore are the targeted stocks for the sockeye salmon adult reintroduction into Cle Elum Lake. Both upper Columbia stocks support terminal area sport and tribal ceremonial and subsistence fisheries when annual run abundance is sufficient.