Biological and economic management strategy evaluations of the eastern king prawn fishery
Department of Agriculture and Fisheries EcoScience Precinct
Tony J. Courtney
Stock assessment of the EKP fishery, and the subsequent advice to management and industry, could be improved by addressing a number of issues. The recruitment dynamics of EKPs in the northern (i.e., North Reef to the Swain Reefs) parts of the fishery need to be clarified. Fishers report that the size of the prawns from these areas when they recruit to the fishing grounds is resulting in sub-optimal sizes/ages at first capture, and therefore localised growth overfishing. There is a need to assess alternative harvest strategies of the EKP fishery, via computer simulations, particularly seasonal and monthly or lunar-based closures to identify scenarios that improve the value of the catch, decrease costs and reduce the risk of overfishing, prior to implementing new management measures. The project is highly relevant to FRDC priorities and directly addresses the FRDC R&D 2005-2010 Plan, namely Program 1 Natural Resources Sustainability, Challenge 1 – Natural Resource Sustainability “Maintain and improve the management and use of aquatic natural resources to ensure their sustainability”. The proposal directly addresses the QFIRAC 2007 R&D priorities for Trawl Fisheries which specifically refer to “Undertaking management strategy evaluations for the Eastern King Prawn fishery, particularly the potential for seasonal closures…”. It also addresses the Queensland TrawlMAC “high” research priorities in relation to improving our understanding of the stock-recruitment relationships and undertaking management strategy evaluations. In summary, there is a strong need for this project, which addresses the high research priorities identified by FRDC, QFIRAC and the Queensland TrawlMAC. It is focused on Queensland’s most valuable fished stock, eastern king prawns.
1. Investigate the recruitment dynamics of eastern king prawns in their northern-most distribution (i.e., the North Reef-Swain Reefs area).
2. Undertake an economic analysis of the eastern king prawn fishery and determine the optimum yield and effort for profitability.
3. Develop (computer) models of the eastern king prawn fishery that evaluate alternative harvest strategies, as identified by the fishery managers and fishers, and provide advice on the efficacy of each strategy in achieving biological and economic management objectives.
Principal Investigator: Tony Courtney
Key Words: eastern king prawn, Melicertus plebejus, recruitment, tag-recapture, fishery economics, maximum sustainable yield, MSY, maximum economic yield, MEY, EMSY, harvest strategy evaluations, fishing power, generalised linear model, GLM, linear mixed models.
Summary: To date, these are the main outcomes achieved by this project: