Estimating Ocean Survival of Columbia River Salmon

John Ferguson1, Edmundo Casillas1, and Bill Peterson2

1  Fish Ecology Division, NOAA Fisheries, Northwest Fisheries Science Center, Seattle WA USA
2  Fish Ecology Division,  NOAA/Fisheries, Northwest Fisheries Science Center, Newport OR USA

Successful prediction of early marine survival of salmonids and recruitment into older age classes requires knowledge of ocean residency patterns, annual variability in the productivity of key habitats, and the processes that determine recruitment.  Over the past 15 years we sampled the continental shelf off Oregon and Washington and monitored climate conditions, hydrography, zooplankton, and juvenile salmon abundance. We developed 16 indicators of ocean conditions, ecosystem productivity, juvenile salmon early marine survival and adult salmon escapement abundance. These indicators are based on physical factors and biological indicators that index the quality of food within the food chain and catches of juvenile salmon during trawl surveys conducted during May, June and September each year.  We display their values in a ‘stoplight’ diagram (shown below): indicators that point to ‘poor ocean conditions’ are assigned a red color; ‘good ocean conditions’ get a green color, and ‘average ocean conditions’, yellow.  The indicators are being incorporated into adult return forecast models to improve harvest management, and life-cycle models being developed in the Columbia River to support salmon recovery decisions.  Detailed information on these indicators can be found at: http://www.nwfsc.noaa.gov> by clicking on “Ocean Conditions and Salmon Forecasting” in the box on the right-hand side of the page.