Sockeye Reintroduction V

This project funded sockeye reintroduction activities occurring during calendar years 2015 and 2016.

The Yakama Nation is implementing a sockeye salmon reintroduction project in the headwater reservoirs of the Yakima River Basin. Prior to impoundment for irrigation purposes, the natural lakes in the upper watershed are estimated to have produced annual adult returns of several hundred thousand. The irrigation impoundment dams were constructed without fish passage facilities and the native sockeye populations were extirpated. This reintroduction effort utilizes wild adult sockeye of Wenatchee and Okanagan stock that are trapped at Priest Rapids Dam and released into Lake Cle Elum. Expansion of the program to other reservoirs in the system is planned as funding sources and feasibility planning are further developed.

This project is a cooperative effort initiated in 2009 between the Yakama Nation and US Bureau of Reclamation, which manages Lake Cle Elum for irrigation purposes. Project funding from USBOR is assured for at least the next 10 years to support one FTE assigned to work with USBOR on the final design of permanent juvenile and adult fish passage facilities on Lake Cle Elum. Once these facilities are operating the fish managers anticipate that increasing returns of naturally-produced adult offspring of the sockeye currently being trapped at PRD and released into the lake will gradually reduce the need to bring in sockeye from outside the basin.

PCSRF funds provided staff and logistical support in 2015 and 2016 to continue two essential elements of the sockeye reintroduction program: 1) the trap-and-haul project that transports adult sockeye salmon from Priest Rapids Dam for release into Lake Cle Elum, and 2) efforts to reduce the abundance of lake trout (Mackinaw) (Salvelinus namaycush), an introduced predator of juvenile sockeye.

Trap and Haul: The trap and haul program used the Off-Ladder Adult Fish Trap (OLAFT) at Priest Rapids Dam on the Columbia River through a cooperative agreement with Grant County PUD to trap adult sockeye migrating upstream to spawning grounds in the Wenatchee and Okanagan river systems. The adults were then transported by truck and released into Lake Cle Elum located in Kittitas County, Washington.

Lake trout Reduction: The effort for the reduction, control, and potential extirpation of the exotic lake trout population introduced into Lake Cle Elum was comprised of two main elements; 1) reduction of the existing population by hook-and-line removals of its members, and 2) interdiction of future spawning events. PCSRF funds were allocated to joint sponsorship with the Washington Dept. of Fish and Wildlife of a lake trout fishing derby in early spring 2015 to raise public awareness of the need to control this invasive species, enhance hook-and-line fishing effort, and increase fishery removals of lake trout. All harvested fish were sampled for length, weight, sex, age, and stomach contents. The Yakama Nation also has successfully advocated for the relaxation of daily bag and possession limits for this exotic piscivore in Washington State recreational fishing regulations, with the ultimate goal being the removal of any possession limit whatsoever.

The second element of the project was accomplished by deploying gill nets during the spawning season (October and November) when adult lake trout come into shallow rocky areas around the perimeter of the lake to spawn.

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. We view 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. The removal of introduced Mackinaw in the lake is seen as a critical part of restoring a self-sustaining sockeye population and natural ecosystem function.