A system dynamics approach for improved management of the Indian Mackerel Fishery in Peninsular Malaysia

This paper presents the results of the system dynamics model application to the Indian Mackerel (IM) fishery in Malaysia. The main objective of this paper is to investigate a more holistic approach to modelling the possibilities for the intractable task of managing an open access fishery. For that purpose, a system dynamics model was used to provide a general framework that incorporates multiple interacting factors which affect the management of the fishery. Such a model, that combines both biological and economic data, is suitable for
fisheries management practices. In this case, three policy scenarios (alongside a business-as- usual scenario) based on a reduction of the number of boats fishing are used to simulate the behaviour of the IM stock. The results show that the optimum level of CPUE is obtained in the case of a reduction of 25% of the total number of boats. In this scenario, by 2050, the predicted biomass of IM adults is 127,432 tonnes, with a catch level of 32,884 for 2,698 boats. This is in comparison to a ‘business as usual’ scenario in 2016 where the biomass of IM adults is 112,384 tonnes, with a catch level of 32,454 tonnes for 4,616 boats. These outcomes allow us, for the first time, to determine the optimum level of fishing capacity and therefore ensure the sustainability of the IM fisheries. Overall, this paper presents a new method to simulate Malaysian fisheries data, and new modelling methods that are not widespread in Malaysian field of fisheries modelling. The model benefits from the current management and data availability.