Toby Patterson, Paige Eveson, Jason Hartog, Karen Evans,

Alistair Hobday, and Campbell R. Davies

Session 2, Talk 2, 18/1/16 @ 1330 hrs

The southern bluefin tuna is a highly migratory and depleted species targeted by a multi-national fishery across three oceans. We present results from electronic tagging conducted by CSIRO since the late 1990s, largely of juveniles tagged in their summer aggregation area in the Great Australian Bight (GAB). This area is the location of the Australian purse seine fishery and is a staging ground prior to the east or westward feeding migrations of juveniles for the Austral autumn and winter. We provide an overview of the juvenile summer residency in the GAB, annual migration timing and summarise available observations of sub-adult and adult SBT moving from the Tasman sea toward the Indonesian spawning grounds. We discuss, also, the implications of the timing and the associated uncertainty in movement rates (both from geolocation error and individual variability) for interpretation of abundance indices based on catch data and approaches for more explicitly incorporating movement information into analysis and population dynamics models of this highly migratory species.

Contact: T. Patterson, CSIRO Marine Laboratories, Australia, This email address is being protected from spambots. You need JavaScript enabled to view it.