AN APPLICATION OF SATELLITE-DERIVED SEA-SURFACE TEMPERATURES TO SOUTHERN BLUEFIN TUNA AND ALBACORE OFF TASMANIA, AUSTRALIA

This paper examines the relationship between thermal features from sat ellite imagery and reported catches of tuna off eastern Tasmania. The satellite data is in the form of sea surface temperature (SST) obtaine d from a National Oceanic and Atmospheric Administration (NOAA) satell ite using an Advanced Very High Resolution Radiometer (AVHRR) sensor. The fishery data is the catch of southern bluefin tuna and albacore fo r the Japanese longline tuna fishery off the Tasmanian coast. The wint er fishing seasons for May to July 1991 and 1992 are considered in det ail. The study focuses on the relationship between southern bluefin tu na and albacore and the occurrence of warm core eddies and thermal fro nts. In 1991 a persistent mesoscale eddy was observed using the NOAA-1 1/AVHRR infrared data. In 1992 there was no similar eddy structure but a strong thermal front occurred. Southern bluefin tuna and albacore c atches tend to occur at the location of the eddy and thermal fronts. A n algorithm that identifies the edges of thermal fronts proved to be a good predictor of the location of productive fishing areas.