Sargassum strandings in the Caribbean - How can we integrate knowledge, innovation, and governance to find a sustainable management solution?

Although of natural origin, Sargassum has proliferated under the combined effects of climate change—warming waters, increased nutrient inputs, and altered ocean currents. The phenomenon has expanded across the entire tropical Atlantic, forming what is now known as the Great Atlantic Sargassum Belt. For several years, this has led to massive Sargassum beachings throughout the Caribbean, creating major environmental, health, and socio-economic challenges. These strandings disrupt coastal ecosystems, affect human health (through hydrogen sulfide emissions and heavy metal exposure), and threaten tourism and fisheries. While research has advanced—particularly in modeling Sargassum movements—accurate forecasting remains difficult due to the variability of oceanic flows and the lack of localized data. Similarly, long-term impacts, especially on human health, remain largely unknown. Attempts to valorize Sargassum through composting, biogas production, or biomaterials remain experimental and site-specific, hindered by the seasonality of the phenomenon and high processing costs. Today, management of Sargassum remains fragmented: local responses, often ad hoc and expensive, struggle to fit into a coherent regional strategy. Could an integrated approach—combining scientific research, innovation, and coordinated action at the Caribbean level—turn this ecological constraint into an opportunity for regional cooperation and circular economy?