An integrated model for marine fishery management in the Pearl River Estuary: Linking socio-economic systems and ecosystems

The paper devises an integrated ecological-economics-social model to assess the implementation of ecosystem-based fisheries management in the Pearl River Estuary (PRE) in the South China Sea (SCS). In particular, this paper presents the development of an integrated model, which links a regional economics social accounting matrix (SAM) model to an ecological model constructed using Ecopath with Ecosim (EwE) software. The impacts on the ecological-economics-social system are examined by varying fishing efforts for four scenarios, including status quo management, fishing effort reduction policy, fishing gear switch policy, and summer closure extension policy. Key results from the predictions (2010-2020) and policy simulations illustrate that the collapse effect is apparent in the status quo scenario. Further, reducing or switching of fishing effort (e.g. elimination of overfishing and reduced habitat disturbance) positively affects the ecosystem and can lead to economic and social welfare gains in the PRE's economy. The gear switch scenario presents a compromise among the economics, social, and conservation metrics, and also outperforms other scenarios in terms of biomass at the end of the simulation period. The fishing effort reduction policy performs better than the summer closure extension policy in terms of the conservation metrics but does relatively poorly in economic terms.