Lake Roosevelt Wild Redband Trout Study

The Redband Trout Stock Assessment Project was initiated in Lake Roosevelt, the portion of the Columbia River impounded by Grand Coulee Dam, by three co-managers in 2010; Washington Department of Fish and Wildlife, Colville Confederated Tribes, and the Spokane Tribe of Indians. The primary goal of the project is to conserve, enhance, and restore native fish populations in the reservoir and tributaries above Grand Coulee Dam, and to provide opportunities for subsistence harvest by Native American Tribes and for recreational harvest.  Because hatchery stocking has been intense in the region, one objective was to use SNP loci to develop a basin wide genetic stock inventory of Redband Trout populations in the Lake Roosevelt watershed to identify remnant native diversity. We found little hatchery introgression and strong native diversity despite years of hatchery planting and alterations to spawning habitat.  We also identified components contributing to the lake fishery.  Regional fisheries managers will use this information to preserve native diversity through habitat restoration, conservation planning, and harvest regulations.