During an international acoustic survey on pelagic redfish (Sebastes mentella) in the Irminger Sea in June–July 2001, a deep-towed vehicle carrying a dual-frequency SIMRAD EK60 Mk1 echosounder was used experimentally to observe and estimate redfish abundance at depths greater than 500 m. Comparison was made with the hull-mounted SIMRAD EK500 echosounder. The deep-towed echosounder improved the spatial resolution of fish in scattering layers as well as the ability to scrutinize and interpret fish echoes. The signal-to-noise ratio was better than that of the hull-mounted system. The fish...
Keywords: deep-towed vehicle; fish-abundance estimation; redfish
Journal Article. 4301 words. Illustrated.
Subjects: Environmental Science ; Marine and Estuarine Biology
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