Management and Monitoring of Fish Spawning Aggregations in the West Coast Bio-Region

This project is a collaboration between the Department of Fisheries, Murdoch University and Curtin University and the University of WA. It will use the latest sonar and video technologies to study spawning aggregations of fish off the west coast, particularly samson fish, WA dhufish and pink snapper. A growing catch-and-release fishery targets large, deep-water spawning aggregations (gatherings) of samson fish near Perth and this may have implications for sustainable management. Samson fish aggregations will also be used to examine a range of methods for studying and monitoring aggregations that may be applied to other aggregating species. Past information has been scarce, largely due to the fact that many aggregations are of short duration and occur in remote and deep locations, making them logistically and economically difficult to study. The high catch rates and large size of fish that may arise from aggregation fishing can also provide false indications about the health of the fishery. The area west of Rottnest Island where the samson fish aggregate appears to be an important aggregating site for other fish including mulloway, grey-banded cod, trevally and snapper. Little is known about the aggregations of these species, although they are increasingly vulnerable to fishing pressure as recreational fishing effort expands offshore. A current investigation of the biology of trevally and mulloway in the Perth region by Murdoch University will also be enhanced by additional information about the aggregating characteristics of these species in adjacent oceanic waters. The project will: * Identify species that aggregate to spawn within the West Coast Bio-region and to describe (e.g. location, size, timing, nature) the aggregations of key demersal species such as snapper and dhufish. * Investigate the biology, ecology and fishery for samson fish with emphasis on the sports fishery targeting deep water spawning aggregations west of Rottnest Island. * Establish methods and protocols for monitoring fish aggregations. * Review relevant information and provide advice on the impact of aggregation fishing and the management of aggregating fish species in WA (with specific advice for key species within the West Coast Bioregion).

Time: Due for completion 2007