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

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.

A Natural History of Floating Sargassum Species (Sargasso) from Mexico

“…The pelagic masses of sargasso arrive on the Mexican coasts approximately 2-3 months after their introduction into the southern Caribbean. Southeastern trade winds transport the sargasso masses accumulated in the Yucatan current towards the Mexican coast inundating the beaches with algae at seasonal intervals from March/April until August/September (Figure 9) [37,84].…”

“…Mexico started to receive unusual quantities of sargasso late 2014, and the first massive beachings were reported in 2015 [4]. A general overview of the massive influx of sargasso into Mexico has been presented recently by Chavez and collaborators [84]. The first significant influx of sargasso was in the summer of 2015, A Natural History of Floating Sargassum Species (Sargasso) from Mexico DOI: http://dx.doi.org/10.5772/intechopen.97230 when on average 319 m 3 of sargasso were removed per km of beach per day in the northern part of the Mexican Caribbean [4].…”

“…The first significant influx of sargasso was in the summer of 2015, A Natural History of Floating Sargassum Species (Sargasso) from Mexico DOI: http://dx.doi.org/10.5772/intechopen.97230 when on average 319 m 3 of sargasso were removed per km of beach per day in the northern part of the Mexican Caribbean [4]. Satellite images of sargasso in front of the Mexican coast revealed large interannual fluctuations in abundance, reaching a maximum cover of 22,900 ha in September 2018 [84]. Generally, large abundance in the ocean corresponded with larger quantities on the beaches, although not all coasts were equally impacted.…”

“…Generally, large abundance in the ocean corresponded with larger quantities on the beaches, although not all coasts were equally impacted. During the peak years of 2018 and 2019, on average 3.2 × 10 3 and 1.7 × 10 3 m 3 were collected per month, per km of beach in the Northern Mexican Caribbean, respectively [84].…”

“…Economic parameters such as the billing rate, jobs, and the hotel activity in this region, did not detect a discernible impact on the state's economies during 2018 and 2019 [2]. However, hotel occupancy has declined and some hotels have invested major efforts in maintaining their beach fronts free from sargasso [84].…”