Massive Influx of Pelagic Sargassum spp. on the Coasts of the Mexican Caribbean 2014–2020: Challenges and Opportunities

TLDR

Since late 2014, the Mexican Caribbean coast has experienced periodic massive influxes of pelagic Sargassum spp., causing mortality of nearshore flora and fauna, beach erosion, pollution, reduced tourism, and high management costs, while also offering potential industrial uses. The study aims to understand the dynamics of Sargassum influxes using Landsat 8 imagery and to promote a circular economy by stimulating local industrial growth based on Sargassum. We analyzed Landsat 8 satellite imagery from 2016 to mid‑2020 to map Sargassum coverage along the coast, noting a peak in September 2018. Analysis revealed spatial variation in beached Sargassum along the coast, and over time, effective beach and offshore collection practices have been developed, with the Mexican government and hotel industry investing millions in removal and detention.

Abstract

Since late 2014, the Mexican Caribbean coast has periodically received massive, atypical influxes of pelagic Sargassum spp. (sargasso). Negative impacts associated with these influxes include mortality of nearshore benthic flora and fauna, beach erosion, pollution, decreasing tourism and high management costs. To understand the dynamics of the sargasso influx, we used Landsat 8 imagery (from 2016 to mid-2020) to record the coverage of sargasso in the sea off the Mexican Caribbean coastline, with a maximum reported in September 2018. Satellite image analysis also showed local differences in the quantity of beached sargasso along the coastline. Over the years, good practice for collection on the beach and for off-shore collection of sargasso have been established through trial and error, and the Mexican Government and hotel industry have spent millions of dollars on removal and off-shore detention of sargasso. Notwithstanding, sargasso also has various properties that could be harnessed in local industries. The stimulation of local industrial growth would offer alternatives to the dependence on tourism, as a circular economy, based on sargasso, is developed.