Modelling sustainable harvesting strategies of a fish pond- A case study
In this thesis, we study sustainable harvesting strategies for tilapia fish farming. Modified logistic growth models with constant harvest rate as well as periodic harvesting have all been studied. Modified logistic growth model is applied to fishery systems and animal production where overcrowding and competition of resources are considered. Although, tilapia fish farming is being done on commercial basis in Ghana, there is much less literature in studying sustainable harvesting strategies. Specific objectives of this thesis were to develop a modified logistic growth model to include harvesting rates. Finally, to determine Maximum Sustainable Yield (MSY) of fish that will ensure the tilapia fish supply is continuous and sustainable. Analytical and numerical methods were used to determine the maximum sustainable yield of fish population in a pond. The existence of equilibrium solutions and their stabilities of the modified logistic growth model were theoretically studied. Periodic harvesting strategy is strongly recommended for the selected tilapia fish farm and inland fish harvesters. This thesis will help improve productivity and reduce risk from changes in sale price of tilapia fish.