Facing oceanographic, fisheries, and governance hotspots: Scientific evidence and policy implications from the southwest South Atlantic Ocean

Abstract

The southwest South Atlantic Ocean (SWAO) is a highly dynamic region where subtropical and subantarctic waters converge, making it one of the world's most productive marine areas. The SWAO is also one of the world’s most intense marine hotspots, with rising sea surface temperatures and climate-induced shifts in species distribution posing significant challenges. This paper investigates long-term trends in key fishery resources exploited by Brazil, Uruguay, and Argentina over the past 70 years, focusing on the transboundary and straddling stocks that dominate the region's catch statistics. Key strengths identified include the use of diverse stock assessment methods, the implementation of effective management measures, and the establishment of collaborative governance systems, all of which have contributed to fostering sustainable fisheries. However, the study highlights the need for adaptive management strategies due to the impacts of climate change, including the tropicalization of species and shifts in fish abundance. Governance challenges are exacerbated by weak coordination among countries and the absence of robust and inclusive international agreements, particularly for managing straddling stocks in international waters. The paper emphasizes the need for an international governance framework aligned with ecological, social, and institutional scales aiming to ensure sustainable fisheries amid climate-induced changes. Recommendations include the development of dynamic and adaptive management approaches, enhanced monitoring systems, and stronger regional cooperation to address the shared challenges in the SWAO. The interplay between climate, biodiversity, and fisheries management and governance is essential for establishing resilient social-ecological systems in this region.