ES60 Water Column Sonar Data Collected During FR0403

Oregon - Washington Sardine Survey. Forty of the forty-two primary stations were occupied after dusk and prior to sunrise. Daytime activities included occupying fine scale patterns relative to the previous station using the ES-60 sounder. At each night station the following activities were performed: a. Deployment of a Seabird SeaCat down to 100 meters, bottom depth permitting. The self-contained CTD collected depth, temperature, conductivity and chlorophyll data. b. A standard Pairovet cast. The Pairovet net was fished from 70 meters to the surface (depth permitting) using paired 25 cm diameter 150 µm mesh nets. The technical requirements for the Pairovet tow was: Descent rate of 70 meters per minute, a terminal depth time of 10 seconds and an ascent rate of 70 meters per minute. c. Standard meteorological data including SST, wind speed and direction, wave height and direction, cloud cover, relative humidity, air temperature and barometric pressure. d. During all transit between stations continuous acoustic measurements were made using the ES-60. e. A Nordic 264 mid-water trawl using 3.0 m² foam core doors was towed at the surface for 30 minutes traveling at approximately 3.5 knots. Every catch was sorted and sardines were sampled.