Temporal Characterization of Sargassum (Sargassaceae, Phaeophyceae) Strandings in a Sandy Beach of Quintana Roo, Mexico: Ecological Implications for Coastal Ecosystems and Management

In the Mexican Caribbean, the magnitude of the Sargassum events and the uncoordinated efforts have made it difficult to achieve successful management. This study contributes to understanding the dynamics of the Sargassum accumulations on a sandy beach in Puerto Morelos, Quintana Roo, through monitoring for 18 months (2018–2019). Temporal changes in the abundance of strandings and species composition (including holopelagic and benthic marine macrophytes) were recorded throughout the study period, with the highest biomass in May 2019 (12.6 ± 3.7 kg m − 2 of dry weight). Nine taxa of Sargassum , three seagrasses, and six taxa of other benthic macroalgae were found at the study site, whose relative abundances changed throughout time. The species S. pteropleuron is reported here for the first time in the Mexican Caribbean; the implications related to its distribution range are discussed. Detailed taxonomic descriptions of holopelagic and benthic Sargassum taxa are included. In addition to massive accumulations of holopelagic Sargassum (53.2–99.4% of the total fresh biomass) for most of the study period (15 of the 18 months), seagrasses were an important component in the strandings, especially during the cold season (reaching up to 76–100% of the total fresh biomass). The ecological implications of changes in species composition and their abundance in the strandings are discussed for coastal ecosystems. This baseline information must be considered to develop sustainable management and promote the conservation of coastal ecosystems. Graphical abstract