Yakama Nation Sockeye Reintroduction IX

The Yakama Nation continued to implement 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 were 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 directly into Lake Cle Elum. This is a straightforward adult reintroduction (no hatchery process is utilized in this project). Expansion of the program to other reservoirs in the system is intended 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 8 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. The adult and juvenile facilities are being constructed in phases as funding becomes available.



PCSRF funds provided staff and logistical support (primarily during 2019 and 2020) to continue an essential element of the sockeye reintroduction program: the trap-and-haul project that transports up to 10,000 adult sockeye salmon from Priest Rapids Dam for release into Lake Cle Elum that occurs annually during the sockeye migration from the ocean in June and July. For this process 2 CDL certified truck drivers, two Fish Tech II, one full-time Fish Tech and Project Lead/Biologist performed the transfer of sockeye from PRD to Lake Cle Elum. Random genetic samples were taken from sockeye adults before the transfer to Lake Cle Elum, and these samples were subsequently analyzed by CRITFC Hagerman Laboratories (non-project funds)



This project occured concurrently with other efforts (funded outside of this project) including:



(a) the reduction of the abundance of Mackinaw (Salvelinus namaycush), an introduced predator of juvenile sockeye, in Lake Cle Elum.



(b) Spawning ground surveys were conducted weekly at Lake CleElum. All redds were GPS’d, and this data was used to determine the range of adults in the Cle Elum and Cooper rivers.



(c) We also estimated population—fry to smolt survival and smolt output—using Hydro Acoustic survey.

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.