Reducing dolphin bycatch in the Pilbara finfish trawl fishery

The incidental capture of cetaceans (whales, dolphins and porpoises) in fishing gear is a serious threat to populations and species worldwide. In Australia, several dolphin populations are being impacted by mortalities through interaction with fisheries, in particular, gillnets, purse-seining, long-lining and trawl fisheries. The capture of dolphins has been a conservation issue in the Pilbara Fish Trawl Interim Managed Fishery (PFTIMF) that was first assessed in 2002 by the Department of Fisheries Western Australia (DoFWA). At that time, an estimated 50 to 100 dolphins were being caught each year. A number of bycatch mitigation techniques were trialed between 2004 and 2007, including pingers (acoustic deterrents) and different exclusion grids, meeting with varying degrees of success (FRDC 2004/068). Due to ongoing dolphin bycatch, successive Ministers for Fisheries have not been prepared to move the fishery beyond ‘Interim Managed’ status. In late 2007, Murdoch University was asked to provide expertise on cetacean behaviour and fisheries interactions in the Pilbara trawl fishery.