Characterization of Argentina's fishing activity in areas susceptible to sea turtle bycatch in the Southwestern Atlantic

Abstract

The high biological productivity of the Northern Argentine Continental Shelf supports several fisheries and constitutes a food source for three threatened sea turtle species: Chelonia mydas, Caretta caretta and Dermochelys coriacea. This study characterizes, for the first time, Argentine fishing activity in areas susceptible to bycatch of these species. The fisheries statistics database (2020–2023), provided by the National Fishing Agency, was analyzed to identify and characterize the vessels and fisheries, quantify fishing effort, and analyze its variation across different zones and seasons. Approximately 240 vessels with diverse characteristics operate in these important areas. The variation in fishing effort among vessels suggests that not all vessels have the same level of impact on turtles. The overlap between fishing zones and susceptible areas, along with vessel numbers and landed tons, indicates that fresh fleet vessels 6.9–26.9 m in length are the most relevant, particularly those around 22.8 m. Fisheries overlapping with sea turtles are mainly demersal multi-species, especially those using bottom trawls and gillnets. These should be considered a priority in future bycatch assessments. Due to the lack of on-board observers across the Argentinean fleet and data collection challenges, these findings provide essential guidance for future bycatch studies. The high variability in fishing effort emphasizes targeting monitoring on the most impactful vessels and adapting bycatch rate calculations accordingly. Given that overlapping fishing areas fall under various administrative jurisdictions, coordinated efforts are crucial for effective bycatch monitoring and conservation.