The goal of the Lake Roosevelt Co-Managers is to conserve and enhance the Burbot population in Lake Roosevelt and provide harvest opportunities for Tribal members and recreational anglers. A goal of this project is to provide information to the Co-Managers that will assist them as they manage to insure the long-term persistence of this population. Information provided to managers consists of stock assessment data collected and analyzed under this project, and through the evaluation of population limiting factors. Recruitment has a large influence on fish populations, and therefore developing an understanding of recruitment mechanisms (limiting factors) is important for conservation and management. Burbot in Lake Roosevelt experience variable recruitment, but the reasons for the variability are unknown. Before we can begin to investigate recruitment mechanisms, we need to develop an understanding of Burbot early life history (ages 0 to 2) in Lake Roosevelt. Specifically, how to sample them effectively, then how they are distributed in time and space. In summary, the goals of this project for the 2021-2025 proposal period are to continue stock assessment, evaluate reproductive assumptions of the population model (fecundity and proportion mature by age), identify spawning areas and timing, determine how to sample pelagic larvae and juvenile life stages, describe the temporal and spatial distribution of pelagic larvae, and develop a plan to describe the temporal and spatial distribution of juveniles.

The activities outlined in this contract comprise the first year of the five outlined in the proposal submitted for the Northwest Power and Conservation Council's 2020 Resident Fish Review. Tasks to be completed in 2024 toward achievement of project goals include:

1) Lake Roosevelt Burbot stock assessment and analysis  (FWIN survey);
2) acoustic telemetry to help identify Burbot spawning locations within Lake Roosevelt;
3) ichthyoplankton surveys to identify distribution and density of pelagic Burbot larvae in Lake Roosevelt;
4) investigations into how and where to capture age-0 juvenile Burbot in Lake Roosevelt;
5) hydrographic surveys to characterize benthic habitat (bathymetry and substrate); and
6) processing of archived ichthyoplankton/zooplankton samples.