Monitor Contribution of Tulalip Hatchery Chinook and Coho to Snohomish Escapements using Otoliths, CWTs and Scales

Differentially thermally mark 100% of Tulalip Hatchery Chinook, coho and chum; recover otoliths, CWTs, scales, and fin tissues for DNA analysis, and process samples at the Tulalip Stock Assessment Laboratory (TSAL). Use results to estimate census (demographic or “D”)- and genetic (“G”)- based hatchery- and natural-origin contribution rates to Snohomish escapements and hatcheries and estimate pNOBD and PNID,G (Wallace and Tulalip Hatcheries) and assess H-vs-W ecological and genetic interactions (juvenile and adult). No funding is requested here for genetic laboratory analysis.

Monitoring hatchery/natural fish enabled by this project is the backbone of the hatchery monitoring program and is mandatory to meet “non-discretionary” Terms and Conditions in final ESA consultation documents for the HGMPs and regional management plans. The project enables the identification of the entire suite of hatchery indicators from initial field sample recoveries, to lab analysis, leading to the successful identification of fish by origin, age and broodyear using thermally marked otoliths, CWTs, and adipose fin clip data. These data are used to estimate H vs W abundances in returning run size, escapement, survival, productivity, distribution, straying and contribution rates, demographic-and genetic-based estimates of pHOS, pHOB, and PNI, genetic mark-recapture estimates, gene flow, relative reproductive success, etc. These estimates enable us to ID hatchery fish from the thousands of other fish in the extensive escapement in a very large river system, plus thousands more in regional fisheries and hatcheries for these purposes.