Ecosystem-based fisheries management in the Pearl River Delta: Applying a computable general equilibrium model

A comprehensive social-economic-ecological framework is applied to evaluate the input and output control policies for fishery management in the Pearl River Delta of China. The paper proposes a computable general equilibrium model that can evaluate changes in the economic and social indicators. This model is connected to an Ecopath with Ecosim model that can simulate the dynamics of an ecosystem. The integrated model is constructed to investigate how different scenarios of fishing effort and catch management reflecting varying levels of input and output in four fishery management simulations result in different states of the socio-economic and ecosystem structure. Four alterative fishing management scenarios are defined, namely: (1) fishing intensity and policies maintain the status quo; (2) fishing vessel reduction is implemented as an input control policy; (3) fishermen are required to transfer to others jobs as an input control policy; and (4) total landing reduction is implemented as an output control policy. The modelling results show that the output control policy has the most positive effect on ecosystem restoration and can increase overall social welfare. The fishermen switching policy leads to the most positive increase in economic indicators, whereas the policy of fishing vessels reduction has a positive effect on ecosystem restoration, but also a considerable, negative impact on the social and economic dimensions. To achieve sustainable utilisation of marine fishery resources, China's fisheries management policies should be developed to enhance total output control and ecosystem reconstruction.