Contract Description:
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 offten referred to as the "blocked area". The Confederated Tribes of the Colville Indian Reservation (CCT) work cooperatively with the Spokane Indian Tribe and the Washington Department of Fish and Wildlife to enhance fishing opportunities in Lake Roosevelt as 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 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 with the objective of increasing naturally produced kokanee abundance. This includes entrainment studies on Grand Coulee Dam, habitat studies to quantify kokanee spawning potential, a basin wide genetics study to understand stock structure, water quality monitoring in key tributaries, and predation impacts on wild and stocked salmonid populations. Adult counts at traps placed in key tributaries to Lake Roosevelt since 2000 have consistently indicated low wild adult escapement (<50 spawning adults). 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 pilot 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 2012 CJKEP has implemented three primary objectives:
Objective 1. Increase the abundance of naturally produced kokanee in the Sanpoil River. To accomplish this objective the project will:
A. Experiment with egg and yearling kokanee plants. The project has contracted (non-BPA funds) with Washington Department of Fish and Wildlife, at the Colville State Hatchery, to provide CCT with 500,000 eyed eggs (otolith marked), and 15-20,000 yearling kokanee (adipose marked yearlings raised at Spokane Tribal Hatchery). CCT has also added a request to Canada to purchase an additional 500,000 kokanee eggs from the Meadow Creek run found in Kootenay Lake (availability of this stock varies per year). Each stocking method will be evaluated for survival from stocking to out-migration, timing of out-migration, harvest in the fishery, adult escapement, and location of spawning within the Sanpoil River.
B. Conduct a non-native predator reduction program. Walleye and smallmouth bass will be targeted with gill nets and boat electrofishing during the key outmigration periods (May - June) at the reservoir/ river interface of the Sanpoil River. A pilot study was conducted in 2011 that experimented with timing, location, gill net mesh size, and gill net orientation. The results will be used to develop a program that limits by-catch of native fish while increasing catch of non-native predators. This program will be implemented in the designated time period during 2012.
Objective 2. Establish a run of naturally produced kokanee in Barnaby Creek. To accomplish this objective the project will (dependent on kokanee egg availability):
A. Begin an experiment with kokanee egg plants in Barnaby Creek. In 2011, the culvert at Barnaby Creek was replaced, which opened up spawning habitat to kokanee. Previously, kokanee could not access Barnaby Creek from Lake Roosevelt in the fall because the culvert was above the fall water levels. Egg planting methods, egg to fry survival and out-migration timing, and adult escapement will be monitored.
Objective 3. Locate wild kokanee spawning grounds within Lake Roosevelt. To accomplish this objective the project will:
A. Build on data to be collected in the fall of 2011 which will determine if wild kokanee utilize the Sanpoil Arm of Lake Roosevelt for spawning. The next focus area will be in the lower reservoir area from Grand Coulee Dam to the Swawilla Basin area. The Keller Ferry area, or mid reservoir will be the third focus area. Hydroacoustic surveys will be used to locate aggregations of fish. The aggregations of fish will be identified by snorkeling, scuba diving, or gill netting.