In “Les algues sargasses, cauchemar des Caraïbes,” David Himbert (Le Devoir) reports on the nightmarish situation that countries and territories in the Caribbean region are facing due to Sargassum seaweed. He reports that, due to this invasion, a severe crisis threatens the economy and the environment as much as the health of local populations. He writes, “Indeed, from the Mexican Riviera Maya to Martinique, via Cuba and the Dominican Republic, thousands of kilometers of beach are invaded, for the third time since 2011, by daily washing ashore and accumulation of piles of brown algae.” He continues:

The many tourists who frequent these tropical paradises to escape the rigors of the winter will have noticed it: day after day, considerable quantities of Sargassum seaweed accumulate on the dream beaches and to spoil the postcard view. An imposing and odorous brown barrier (the decomposition of algae gives off a strong smell of rotten eggs) now separates the immaculate white of the sand and the turquoise blue of the ocean, and begins to discourage travelers, as evidenced by the messages of discontent and warning that accumulate on sites like TripAdvisor. In addition, an expert report updated in March 2017 by the French National Health Security Agency (ANSES) notes that in Guadeloupe, in 2015, several restaurants closed during the last seaweed invasion and that hotels have lost up to 50% of their annual turnover.

Therefore, the crisis represents a real threat for the entire Caribbean, whose economy is mainly based on tourism revenues. This is why every morning, whether they are in Playa del Carmen, Saint Lucia or Punta Cana, boaters attend an incessant coming and going of workers, more or less well equipped, dedicated to collecting seaweed. Depending on the wealth of the countries concerned, different means are deployed, ranging from earthmoving machines made available by the French State on the coasts of Guadeloupe and Martinique to the simple fork and wheelbarrow for the 4000 Mexican workers deployed for the task. The fishing industry, the other pillar of the Caribbean economy, is also affected by the crisis as seaweed banks accumulate in ports and damage equipment. [. . .]

Warming and pollution

This proliferation of Sargassum seaweed has its origins in the Amazon Gulf, where the second largest river in the world discharges almost 20% of the world’s freshwater into the ocean. It is here that we can observe a new Sargasso Sea (in reference to the region, rich in vegetation, of the Atlantic Ocean discovered by Christopher Columbus) an area conducive to the growth and development of seaweed by a combination of potentially favorable factors.

Among these factors, the ANSES experts mention the warming of the seas, a direct consequence of global warming, which creates a favorable environment for proliferation. They also question the climatic peculiarities of 2010, the year in which lower winds and lower frequency of storms were observed, which may have favored the concentration of nutrients in calmer waters. But it is especially towards the human activity around the Amazon River that one must turn to understand the phenomenon. Every day, countless quantities of polluted water are poured into the river. Pollution caused by the bad treatment of wastewater, and especially by the dumping of heavy metals, including mercury, by miners who use them to amalgamate gold. In addition, agriculture and intensive land-clearing, also at the origin of the influx of nutrients (phosphates, nitrates), are determining factors in the growth of algae. [. . .]

[Excerpts translated by Ivette Romero. For full article in the French original, see https://www.ledevoir.com/vivre/voyage/524024/reportage-les-algues-sargasses-cauchemar-des-caraibes.]