In 1939, construction of Grand Coulee Dam blocked anadromous fish from 1,835 linear stream kilometers of spawning and rearing habitat in the upper Columbia River, causing the extinction of upper Columbia River Chinook (Oncorhynchus tshwaytscha), coho (O. kisutch), sockeye (O. nerka), and steelhead (O. mykiss).  Collectively, these fish accounted for approximately 1.1 million adult migrants to the upper Columbia River annually (Scholz et al. 1985).  The completion of Grand Coulee Dam also altered the natural ecology of the area by inundating about 243 river km of the upper Columbia River, creating Franklin D. Roosevelt reservoir.  Inundation of the upper Columbia River and subsequent hydro-operations changed the system from a river to a lentic habitat, leading to resident fish extinctions of redband, cutthroat, and bull trout (Bryant and Parkhurst 1950; Earnest et al. 1966).  The loss of wild, indigenous anadromous and resident fishes combined with major environmental changes resulted in a substantial ecosystem perturbation to the upper Columbia River.  

In the 1980’s, the stakeholders around Lake Roosevelt began requesting a return of a fishery in the reservoir, and began their campaign by starting up the volunteer net pen project.  Today, the Washington Department of Fish and Wildlife (WDFW), Spokane Tribe of Indians (STOI), Colville Confederated Tribes (CCT), and Lake Roosevelt Development Association/Volunteer Net Pen Project are cooperating in a comprehensive artificial production program to produce kokanee salmon and rainbow trout for annual release into the reservoir.  The Lake Roosevelt Fisheries Evaluation Program was developed to assess the effect of the supplementation program on native resident fish and the ecology of the reservoir, and to assess the effect of hydro-operations on the artificial production program, the native fishery, and the Lake Roosevelt ecology as a whole.

The Evaluation Program’s primary objectives are to monitor and evaluate the performance of the Lake Roosevelt artificial production program and to assess the impact of reservoir operations on the fishery and ecology of Lake Roosevelt.  

FY2011 Work:

Limnology and Fisheries Monitoring:  We plan to complete water quality, chlorophyll and zooplankton community surveys to monitor physical, chemical and population indices for lower trophic levels.  Through fish surveys, we plan to collect fish length, weight, identifying markings, origin, species, and diet data to assess wild and hatchery fish population status and age structure, fish condition and growth, production, habitat use, and predation effects.  The primary purpose of these activities is to measure shifts in fish community structure, identify changes in growth rates of fish, and determine fish feeding behaviors.  This data will assist managers in determining whether hatchery fish are interacting with wild fish, if growth has changed over time, and whether food is limiting.  Understanding long-term changes potentially provides insight into how the fish community is evolving.  The information will be used to create informed recommendations regarding hatchery stocking strategies, fish regulations and other management decisions to minimize impacts to wild fish and lower trophic levels while maximizing the success of the hatchery program.   We also plan to estimate population size, age, health and habitat use of predators with tested walleye indexing techniques (Fall Walleye Index Netting-FWIN), and to begin initial steps towards assessing redband trout populations in Lake Roosevelt and the upper Columbia River.

Creel:  We will assess recruitment to the fishery using a reservoir-wide creel.  One of the primary objectives will be to monitor wild and hatchery rainbow trout and kokanee.  Walleye and smallmouth bass are also monitored due to their potential impacts to the artificial production program and to the wild fishery.  Indices that will be calculated include: annual harvest, catch rates, the economic value of the fishery, the number of wild and hatchery origin fish harvested, and growth and size of fish harvested.  Creel survey protocols were re-designed in 2005.  A secondary review of the revised protocol was started in 2010 and will be continued in 2011 using a creel-specialist biostatistician.  The objective is to further refine both the creel analysis program and the design and protocols for creel data collection based on the assessment of the effectiveness of the survey design.

Model:  Model runs using the Lake Roosevelt Ecology Model indicate that the Spokane Arm contributes a significant portion of the nutrients to Lake Roosevelt that supports the predominantly pelagically feeding fish community in Lake Roosevelt.  Revisions to incorporate the expanded information for the Spokane Arm of Lake Roosevelt has been completed.  In 2011, we plan to work with model developers (Dr. Wells, Portland State University) to complete model runs that assess specific water use scenarios and their impacts.  If possible, we will take the opportunity to train project participant staff to use the model with reduced assistance from the modelers.

Tag Returns: We will continue to collect tags inserted into hatchery rainbow and redband trout in paired release studies in an effort to determine the best stocks and release strategies to maximize harvest while minimizing entrainment and negative impacts to wild fish.  Tag drawings will be conducted in April and in October as an incentive for anglers to return Floy ® tags and fish information.

Fall Kokanee Collection:  We plan to collect hatchery kokanee eggs and milt from an adult weir trap placed below Hawk Creek falls.  Fish/eggs will be transferred to the Spokane Tribal Hatchery where fish will be spawned and eggs incubated and fish raised for a subsequent yearling release back into Lake Roosevelt.  Collection of returning kokanee will assist managers with enhancing hatchery kokanee production on Lake Roosevelt.

Acoustic Kokanee Study:  We plan to finish data collected from temperature and depth sensitive acoustic transmitters inserted into kokanee to determine their seasonal habitat use.  We will be able to determine whether kokanee make diel migrations into warm sub-optimal temperatures to feed on zooplankton in the photic zone, the location, duration and extent of vertical migrations into sub-optimal water temperatures and potentially to identify unknown areas of thermal refuge utilized by kokanee during the critical summer months.  Additionally we will be acoustic tagging and tracking hatchery kokanee to assess micro habitat use six months after the May release.  If the yearling kokanee stay in localized areas after release, then micro fisheries can be setup through the lower sections of the reservoir, where kokanee are traditionally found in the summer months, presumably due to more favorable conditions for kokanee survival and growth.

Upper Columbia River Trap Studies:  We plan to assess the presence, proportion of the wild population, and genetic "purity" of the redband trout stocks in the Kettle River,

Public Outreach and Coordination:  We also plan to continue public outreach and coordination efforts through the Kettle Falls Water Festival and the Lake Roosevelt Student Discovery Week.  In September 2011 and May 2012 we plan to participate in outdoor events teaching students about invertebrates, pollution, the environment and Lake Roosevelt.  Coordination will remain a critical component of the Evaluation Program in order to foster interaction and communication between Lake Roosevelt co-managers, researchers, the net pen coordinator, and hatchery managers and personnel.  We will organize and/or participate in LRFEP meetings, Lake Roosevelt Management Team meetings, Lake Roosevelt Hatchery Coordination Team meetings and other fisheries forums and meetings necessary to the successful implementation of the program.