Identification of squid echoes in the south Atlantic

During a research cruise of the British Antarctic Survey ship RRS James Clark Ross in February 1996, a substantial number of the ommastrephid squid, Martialia hyadesi, were caught in a pelagic trawl, near the Antarctic Polar Frontal Zone in CCAMLR Subarea 48.3. This paper describes acoustic data gathered during this haul and a survey of the immediate vicinity, in order to characterise an acoustic signature that may be used to identify this species of squid.