Management options for the South Australian rock lobster fishery (Jasus edwardsii) fishery: a case study of co-operative assessment and policy design by fishers and biologists
A modelling workshop process was used to bring biologists and commercial fishers together to develop a spatial model for population dynamics and harvest regulation of the South Australian rock lobster (Jasus edwardsii) fishery. The resulting model provided a credible reconstruction of how the space, time, and size structures of the stock have changed over the history of the fishery, and offers a rich variety of regulatory policy options for exploration of how the stock might have behaved (and might behave in the future) if managed differently. Initial use of the model has been to test options for reducing risk of recruitment overfishing by increasing spawning stock and egg production. A number of regulations ranging from increased size limits to large spatial refuges could accomplish this risk reduction aim. One option is to simply reduce the fishing season length dramatically. The model predicts that short-term yield loss under this strategy would eventually be regained through increased survival and higher catch rates of larger lobsters, and offers the economic advantage of greatly reduced fishing costs. This policy hypothesis can be tested in the field by a management experiment allowing fishers to see for themselves whether an area with a short season does indeed result in catch rates high enough to compensate for fishing time loss