2025 and 2026 Snohomish River Basin Juvenile Outmigration Monitoring

The purpose of this project is to provide a direct measure of juvenile Chinook and Coho migration from the Skykomish River, Snoqualmie River to the Snohomish River. To obtain this information the Tribes will operate two rotary screw fish traps on the lower Skykomish and Snoqualmie rivers. The traps will be operated from February through the middle of June. Each trap will be calibrated throughout the season using groups of marked hatchery fish. Information reported will include numbers caught, effort, timing and trap efficiency, information needed to evaluate production. Reporting will also include estimates of total outmigration numbers (production).

The recovery of these species depends upon improving the effectiveness of habitat, harvest, and hatchery management across the basin. In order to achieve such improved effectiveness, additional information is necessary to fill important data gaps within the Snohomish system and to assess impacts of restoration efforts, including information on Chinook and Coho salmon abundance, productivity, spatial structure, and diversity (Snohomish Basin Salmonid Recovery Technical Committee, 2005) . Information about the trends and inter-annual variability in these population parameters is critical to inform salmon recovery efforts, provides basic information on the productivity and capacity of the system, and can lead to significant improvements in harvest management modeling and run forecasting. Additionally, the monitoring of production and survival along with other physical, chemical, and biological conditions provides a means to evaluate recovery actions, habitat conditions, and potential ecological trajectories in the basin.