2009/714.20 Decision support tools for economic optimisation of Southern Rock Lobster

By Rick McGarvey

The Southern Rocklobster fishery is the most developed of the fisheries included in this series of projects because sophisticated bioeconomic models and stock projection capacity had already been advanced through previous research. This research takes the process further to extend the modelling tools to other states and to examine the use of economic control rules. This means, for example, that it would be possible to evaluate how feasible it would be to target maximum economic yield in the face of price volatility. This level of bioeconomic analysis capability is only available elsewhere in Australia in the Northern Prawn Fishery, Australia's best example of the use of economic data for management to increase profits.

This project also aimed to produce bioeconomic analysis tools for Southern Rocklobster fisheries and determine management strategies using economic models. Economic data for Tasmania were collected, and a lobster fishery projection model was produced which permits the testing of a wide range of strategies, specifically to evaluate each strategy’s economic performance. Using this model, the profit expected under each strategy was estimated.While the analysis showed a small impact of opening the fishery for all 12 months, this analysis is only preliminary and is greatly limited by the lack of any data for winter fishing in South Australia since these two zones have been closed to winter fishing to date. The best policy was a yearly quota-setting harvest control rule designed to seek an approximately constant yearly harvest fraction (a constant exploitation rate). By setting the total allowable catch yearly to remove an approximately constant fraction of the available lobster biomass, three of four important management objectives were optimised.