Laying the foundation for ecosystem-based fisheries management in the Eastern Ionian demersal fishery

Abstract This study presents a practical framework for integrating ecosystem indicators into fisheries management and applies it to the demersal fishery of the Eastern Ionian Sea (EIS) in Greece. The EIS represents a typical Mediterranean multispecies, mixed fishery exploited by two main fleets: a large-scale industrial fleet and a small-scale coastal fleet (SSF), primarily catching European hake, red mullets, and deep-water rose shrimp. The framework combines the outputs of an ecosystem (EwE) and a bio-economic model (FLBEIA) both parameterized with the same historical stock assessment data and projected under the same effort control and climatic scenarios. It applies a multispecies management approach in which the pretty good yield (PGY) ranges for key stocks are further constrained by additional management objectives. Through extensive simulations, a wide range of ecosystem, biological, socio-economic, and global indicators were estimated and analyzed across varying effort levels. By overlaying PGY ranges of key stocks with optimal ranges of ecosystem and socioeconomic indicators, a multi-objective optimal effort zone was identified, whereby ecological sustainability, economic viability, and broader ecosystem goals align. The optimal effort zone is projected to shrink under future climatic scenarios, mostly affecting the viability of the SSF. Results highlight the critical role of SSF management, though its marginal economic viability and data limitations necessitate finer-scale monitoring of individual métiers to support more targeted measures. This study represents the first application of the pretty good multispecies yield concept in input controlled Mediterranean fisheries, and a preliminary attempt towards the implementation of ecosystem based fisheries management in the EIS. As a next step, alternative management objectives can be explored within the optimal effort zone, offering flexibility to address diverse goals and the potential to incorporate stakeholder input into the decision making process.