Ocean drifters’ displacement compared to Sargassum spp. distribution in the Mexican Caribbean

Abstract

Given the impacts of Sargassum spp. fluxes on the environment and society, there is a need to better understand the cover and displacement dynamics of this macroalgae at a local scale. The advances in telemetry and remote sensing technologies allow us to integrally assess the association between Sargassum coverage and the ocean surface movements at scales of tens to hundreds of kilometers. This study aimed to synthesize the displacement patterns of surface drifters and evaluate their association with historical patterns (2014–2020) of satellite-detected Sargassum coverage. Between 2019 and 2021, we deployed 20 satellite-tracked drifters (known as DORIS) in the southern Mexican Caribbean. Using multivariate tools, we assessed an overall residency time spatial index based on their surface displacement patterns and evaluated their spatial configuration. We compared the historic satellite-detected Sargassum coverages with the DORIS displacement patterns. The drifters depicted close-to-shore coherent shape displacement patterns and fast offshore streaming displacement. The region between southern Cozumel and Tulum exhibited the slowest DORIS displacement and, consequently, the longest residency time in the region, coinciding with the area where the satellite-detected Sargassum presence was characterized by high recurrence and intense, frequent episodes. These results enhance our understanding of a local oceanic recirculation area in the Mexican Caribbean, while also strengthening Mexico's technological capabilities for procuring resilient oceans and the essential conditions necessary for sustaining the livelihoods of local coastal communities.