Distribution, growth, and condition of salmonids in the central California Current Ecosystem.

The Fisheries Ecology Division of NOAA’s SWFSC conducted annual surveys of salmon and their ocean habitat in the coastal waters of northern California and southern Oregon from 1998-2016. We used a surface trawl to collect juvenile and subadult salmonids, including several ESA-listed populations of Chinook and coho salmon and steelhead. We also quantified other coastal pelagic fish and invertebrates that co-occur with salmon, and we measured spatially matched biological and physical oceanographic variables. Juvenile salmon were frozen at sea and transported back to shore for further analysis. Scales, DNA, otoliths, stomach contents, blood plasma, and implanted tags (if present) were retained. The majority of older salmon and bycatch species were released alive at sea. Additional data recorded during our survey included seabird counts, plankton samples, echosounder readings, and CTD profiles of temperature, salinity, chlorophyll, transmissivity, and PAR.