Predicting métier used in a multi-gear coastal fleet

Detailed data on fishing gear, species caught, and target species are essential to assess fisheries' environmental impacts and operational patterns. Yet, obtaining such data remains challenging, particularly within multi-gear fishing fleets where vessels employ diverse methods to capture numerous species throughout the year.

The Portuguese coastal multi-gear fleet, consisting of around 500 vessels (ranging from 9 to 35 meters), exemplifies this complexity. Only about one-third of these vessels use electronic logbooks, recording catch data, type of gear used, and fishing locations. This gap leaves many trips without comprehensive data, making it difficult to fully quantify fishing efforts and their impacts at the national level. Certain gear types, such as gillnets and trammel nets, are notably non-selective, leading to bycatch of various species, while others, like longlines, are more targeted but still subject to overexploitation.

Monitoring data collected during fishing operations is essential to track and mitigate harmful practices. Previous studies that modeled gear usage based on sales data have not been successful in the estimation of métier-specific fishing effort—defined as the effort related to fishing activities targeting similar species using similar gear within a specific season or region—limiting the development of strategies to address overfishing.

The increased availability of large datasets has opened new possibilities for classifying and predicting fishing patterns. Through a custom analytical routine, this study leveraged sales notes and electronic logbook data to identify potential métiers within the Portuguese multi-gear fleet. To capture seasonal and regional variations, the findings were validated using a multi-faceted approach, including fishers’ interviews, consultations with fisheries scientists, and onboard observations. By strengthening our knowledge of métier-specific fishing efforts and their environmental consequences, this approach supports better management practices and policies combating overexploitation, promoting sustainable fisheries management in the long term.