The potential impacts of exploitation on the ecological roles of fish species targeted by fisheries: A multifunctional perspective

Examining ecosystem functioning through the lens of trait diversity serves as a valuable proxy. It offers crucial insights into how exploitation affects the specific ecological roles played by fisheries targeted species. The present study investigates the potential impacts of exploitation on the ecological roles of fish species targeted by fisheries through an examination of trait diversity. It focuses on the trait diversity of fish landed by local and coastal fleets in the Azores archipelago over the past four decades. Fourteen functional traits were merged to data on fish assemblages landed by both fishing fleets from 1980 to 2020. These traits corresponded to four fundamental fish functions: habitat use, locomotion, feeding and life history. Variability in functional diversity metrics (i.e., functional richness- FRic, functional evenness- FEve, functional divergence-FDiv, and functional dispersion- FDis) among fleets, functions and across decades was assessed using null models. The results revealed similar trait diversity between assemblages landed by local and coastal fishing fleets with overall trait diversity remaining relatively stable over time. However, fishery activities targeted a wide range of functional traits. Additionally, seasonal availability and increased catches of certain fish species can significantly alter trait diversity and their associated functions. The findings highlight the importance of addressing fishing impacts on species traits and their ecological roles, which is crucial for long-term fisheries and ecological sustainability.