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.  

Current FY Work:

Limnology and Fisheries Monitoring:  We plan to complete water quality, chlorophyll and zooplankton community surveys to monitor physical, chemical and population indices such as standing crop for zooplankton.  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 changing.  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 while maximizing the success of the hatchery Rainbow Trout fishery.  We also plan to index population size, estimate age, and habitat use of predators with tested Walleye and Northern Pike indexing techniques (Fall Walleye Index Netting-FWIN; Spring Pike Index Netting-SPIN), and to continue steps towards assessing wild redband trout populations in Lake Roosevelt and the upper Columbia River through population reconstruction via annual age-length keys.

Creel:  We will assess recruitment to the fishery using a reservoir-wide creel.  One of the primary objectives will be to monitor the fisheries for wild and hatchery rainbow trout and kokanee.  Walleye and smallmouth bass are also monitored due to their popularity and potential influence on the artificial production program and the wild fisheries. The White Sturgeon fishery is also being evaluated using our standard creel and provides a consistent metric for the evaluation thereof.  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 size of fish harvested.  Creel survey protocols were re-designed in 2015 following a secondary review of the 2005 protocol using a biostatistician and this survey has been in place in the current form since 2016 with a slight tweak to the design for 2024 and beyond.  The objective was 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.  

Kettle River: Kettle River and its tributaries will be monitored for native redband trout, hatchery rainbow trout, wild kokanee, hatchery kokanee and burbot.  Individuals will be weighed, measured, pit tagged and fin clips for genetic tissue samples will be collected.  Data will be used to determine 1) the presence and extent of occurrence of redband trout in the system, 2) determine the proportion of redband trout in the overall wild rainbow population, and 3) determine the genetic "purity" of the redband stock(s), presence of wild vs. triploid kokanee.

Acoustic Study:  We will assess native fish reservoir dispersal, habitat use, and movement patterns. Fish tagged will be monitored passively with 26 remote receiver stations placed through the middle and lower sections of the reservoir as well as one below Grand Coulee Dam in Rufus Woods. This array system is complemented by the sturgeon array setup in the middle and upper sections of Lake Roosevelt and Canada. Array downloads will occur monthly.

Native Mussel Assessment: The primary goals of this study are to better understand diversity, abundance, and distribution of native mussels that occur in the waters that are culturally significant to the Spokane Tribe of Indians.  Secondary goals are to better understand the health and condition of the mussels, so that we may investigate potential explanatory variables and how they influence native mussels. This project has two primary components.  1.) Collect water samples, which will be analyzed for eDNA and help to determine which species are present or absent in the system.  2.) Conduct qualitative and/or quantitative surveys to determine abundance and distribution, as well as overall condition/health status of the mussels.  This will include a qualitative presence/absence survey with randomized locations to start.

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 and May 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.