The construction of Grand Coulee and Chief Joseph dams on the Columbia River in 1939 and 1956 blocked anadromous fish passage. The area above the two dams is often referred to as the "blocked area". The Confederated Tribes of the Colville Indian Reservation (CCT) work cooperatively with the co-managers of Lake Roosevelt to enhance native fish populations and fishing opportunities as partial mitigation for the loss of anadromous fish (resident fish substitution). The Chief Joseph Kokanee Enhancement Project (CJKEP) is one such resident fish substitution project. This project was amended into the Council's Fish and Wildlife program during the 1995 amendment process and its first year of implementation began in 1996. The goal of the CJKEP is to protect and enhance the naturally producing kokanee Oncorhynchus nerka populations above Chief Joseph and Grand Coulee dams in an effort to support the tribal subsistence and non-tribal recreational sport fisheries.

Since its inception, the CJKEP has strived to identify and address factors limiting naturally produced kokanee populations. Previous research focused on entrainment studies on Grand Coulee Dam, habitat studies to quantify kokanee spawning potential, basin wide genetics studies to understand stock structure, water quality monitoring in key tributaries, and predation impacts. Kokanee adult escapement estimates in CCT Reservation tributaries have documented a consistent downwardly trend since the early 1990’s.  Escapement in the Sanpoil River averages less than 20 adults a year, and the population is considered extinct. However, a wild kokanee population exists in Lake Roosevelt and contributes between 50-80% (depending on the season) of the overall kokanee harvest. The wild kokanee average between 380 and 590 mm total length (15 - 23 inches), making it a high quality, desirable fisheries resource.

A recent genetics study, using microsatellite DNA techniques, conducted by Kassler et al. (2010) indicated that the wild kokanee stock in Lake Roosevelt is distinct from sources found in the upper Columbia River in Canada, and is unique to Lake Roosevelt. However, the source of the population is unknown. To date, large numbers of wild kokanee have not been detected spawning in tributary streams, leading biologists to hypothesize the wild populations are utilizing deep water spawning habitat at depths below the drawdown elevations (> 17 m). Water quality and habitat surveys conducted in the Sanpoil River drainage in 2009-10 found areas that had conditions indicative of high quality kokanee spawning. Model results suggested the Sanpoil River could support a spawning escapement of 238,464 to 1,703,315 kokanee. The spawning habitat is currently being underutilized in the Sanpoil River. In order to determine the reasons for the underutilization, a predation impacts study was initiated in 2010 to quantify non-native predator (walleye and smallmouth bass) consumption of kokanee and rainbow trout out-migrating from the Sanpoil River to Lake Roosevelt. The bioenergetics model indicated walleye and smallmouth bass consumed 94.7% of the kokanee fry and 40.1% of the kokanee yearlings planted.  These unsustainable values prompted a predator reduction study in 2011 to experiment with decreasing predator densities in the Sanpoil Arm to increase kokanee survival.

To reach the primary goal of enhanced wild kokanee populations in the blocked area, the 2014 CJKEP has implemented two primary objectives (Lake Roosevelt Guiding Document, Lake Roosevelt Kokanee Management Plan):
Objective 1. Increase the abundance of naturally produced kokanee in tributaries on the CCT Reservation and “North Half”. To accomplish this objective the project will:
A. Stocking: Experiment with egg and yearling kokanee plants in the Sanpoil River and/or other tributaries deemed adequate for kokanee production. The project will coordinate with WDFW and the Spokane Tribe to obtain up to 1 million kokanee eggs (otolith marked) for planting. The CCT prefers the Meadow Creek stock of kokanee, however if Meadow Creek stock are not available, the Tribe will use the Lake Whatcom stock. The project will also coordinated with the co-managers of Lake Roosevelt to obtain 20,000 yearling hatchery kokanee (5-7 per lb) to be acclimated (1 month rearing in a net pen or direct planting) and planted in the Sanpoil River, or Sanpoil Arm (reservoir area) as a put-and-take fishery for Tribal members and non-tribal anglers in the Keller area. These fish will be adipose fin clipped (indicate hatchery origin), as well as coded wire tagged for predator consumption monitoring.  
B. Evaluation: Each stocking method will be evaluated for survival from stocking to out-migration, timing of out-migration, harvest in the fishery, and adult escapement.
C. Predator Reduction: Conduct a non-native predator reduction program on the Sanpoil River Arm (inundated area of the river). Walleye and smallmouth bass will be targeted with gill nets and boat electrofishing during the key outmigration periods (May - July) at the reservoir/ river interface of the Sanpoil River. Results from 2011-13 studies that experimented with timing, location, gill net mesh size, and gill net orientation will be used to refine removal techniques to reduce non-target mortalities (i.e. reduce catch rates of native fish).  
Objective 2. Locate wild kokanee spawning grounds within Lake Roosevelt. Between 2011 and 2013 CCT used hydroacoustics in an attempt to identify schools of fish at depths below 15 m, which is the presumed minimum depth of wild kokanee spawning due to reservoir drawdown. No schools of kokanee were found in the Sanpoil River Arm, or the area from Grand Coulee Dam to Swawilla Basin. In 2012, we began collaborating with Pacific Northwest Laboratories to assist us with developing a study plan to use geochemical analysis to look at gradient changes of key substances (Sr, Ba, Mn, Pb, etc) in water samples and invertebrates (mussels) that would also likely be recorded on kokanee otoliths as well.  These chemical signatures could be used to map the spatial life history of kokanee in the lake and thereby approximate spawning ground location. Once the general area is known, finer scale techniques (hydroacoustics) will be used to locate schools of fish.          

Results from the above projects will assist the CCT with managing both hatchery and wild kokanee populations found within the blocked area.