The two most important Chinook salmon stocks for fisheries in California — the Sacramento River Fall Chinook and the Klamath River Fall Chinook — were designated as overfished in 2018. Assessment errors could have contributed to the decline. Regulatory agencies use forecast models before each season to set harvest levels and to develop long-term management strategies. For Sacramento River Fall Chinook, a preseason overforecast of abundance resulted in overharvesting.
National Marine Fisheries Service-Sea Grant 2022 fellow Emily Chen proposes to evaluate changes in the Sacramento River Fall Chinook population’s precocious maturation rate and adult natural mortality. She will reconstruct past cohorts and evaluate alternative models for forecasting abundance, focusing specifically on incorporating age structure data.
Including this information in forecasting models could improve the accuracy of preseason predictions and help overfished stocks such as the Sacramento River Fall Chinook and the Klamath River Fall Chinook recover.