Bayesian Belief Network to explore combined effects of socio-political and climate change scenarios for an artisanal fishery in the Western Mediterranean

Worldwide climate change will influence the spatial distribution and status of exploited fish stocks, often in uncertain ways with cascading effects on social-ecological systems depending on them. Likewise, changes in socio-political conditions influencing consumer demand, fuel and fish prices may jeopardize the viability of fisheries. Predicting whether existing management systems can adapt to these changes is key and especially challenging in data-poor fisheries. In the Mediterranean Sea, the sub-tropical dolphinfish (Coryphaena hippurus) is at its northernmost reproductive distribution area and has sustained a seasonal age-0 based artisanal fishery since ancient times. We built a quantitative Bayesian Belief Network (BBN) model integrating a diverse set of ecological, social and economic input data to assess the impact of plausible mid-term futures (2040-2059) on the seasonal economic profit for dolphinfish fishers in Mallorca (Balearic Islands, Western Mediterranean). These future scenarios accounted for increasing sea surface temperature based on global IPCC projections, population dynamics and growth of dolphinfish, economic forecasts of future fish and fuel prices, and stakeholders’ views on feasible adaptations of the local management system. The model was built under the Horizon 2020 project CERES and it was fully parameterised with quarterly aggregated local fisheries statistics data. For details on the model development, parameterisation and use please refer to the upcoming publication in Ecology & Society or contact the lead author.