EK60 Water Column Sonar Data Collected During DS0604

California Current Ecosystem Survey 2006. The 2006 California Current Ecosystem Survey used two vessels: the NOAA FSV Oscar Dyson and the NOAA FRV David Starr Jordan. The plan was for the FSV Oscar Dyson was to survey the northern part and the FRV David Starr Jordan to survey the southern part using identical methods. However, equipment failures prevented trawling operations on the FRV David Starr Jordan, and trawling was only conducted from the FSV Oscar Dyson and the survey plan of the FSV Oscar Dyson was extended to cover the entire West Coast down to San Diego, California. Both vessels collected water samples from a CTD-rosette, ichthyoplankton samples from plankton nets and meteorological data from weather station sensors at prescribed and adhoc stations. At some of these and other locations, surface trawls were collected during night from the FSV Oscar Dyson. Underway operations on each ship included operating a continuous underway fish egg sampler (CUFES), an acoustic Doppler current profiler (ADCP), multiple-frequency split-beam echosounders and a multi-beam echosounder. Daytime underway operations included bird and mammal observations. The acoustic surveys were accomplished using Simrad EK60 split-beam echosounders. Four echosounders were operated on the David Starr Jordan at 38, 70, 120 and 200 kHz, and five were operated on the Oscar Dyson at 18, 38, 70, 120 and 200 kHz. Each 5 echosounder was calibrated prior to the survey using the standard sphere method.