Reducing drifting Fish Aggregating Devices number and impacts through cooperation

Drifting fish aggregating devices (FADs), equipped with echosounder buoys, are highly effective tools that significantly enhance tuna catchability for purse seine vessels. FADs are also responsible for various externalities, highlighting the need to develop strategies aimed at reducing FAD numbers. In this study, we explore the potential of knowledge sharing among vessels as a means to reduce FAD numbers while maintaining purse seine fleets profitability. By developing an Agent-Based Model, built upon a pelagic species behavioral model, we demonstrate that a four-fold reduction not only improves vessel profitability by cutting private costs and increasing revenue, but it also strongly decreases social costs, such as carbon emissions and FAD stranding. However, this approach also highlights trade-offs, as it leads to a slight increase in silky shark bycatch. Therefore, careful consideration will be required to balance these outcomes and guide future FAD management strategies.