CubaHeadlines

Record-Breaking Sargassum in the Caribbean in 2025 Raises Concerns for Cuban Beaches and Swimmers

Thursday, July 3, 2025 by Olivia Torres

A historic surge in sargassum accumulation across the Caribbean Sea, the western and eastern Atlantic, and the Gulf of Mexico has sounded alarm bells throughout the region, impacting several coastal areas, including parts of Cuba. Citing a report from the Optical Oceanography Lab at the University of South Florida, the Associated Press noted that in May 2025, sargassum levels reached an unprecedented 38 million metric tons, marking the highest amount documented since research began on the Great Atlantic Sargassum Belt in 2011.

The previous record, set at 22 million tons, was noted in June 2022, according to the news agency. The current accumulation has already led to temporary school closures in French Caribbean territories, public protests in islands like St. Maarten due to the foul odors and pollution, and special operations involving heavy machinery in tourist hotspots.

In the insular Caribbean, hotels have shouldered the expense of cleaning efforts, while places like the Dominican Republic have erected barriers to curb the spread of the algae. The ecological impact is significant: sargassum blocks sunlight, suffocates coral reefs and seagrass beds, and upon reaching the shore, it kills the organisms it carries. It also releases toxic gases such as hydrogen sulfide and ammonia, which pose health risks to humans.

In Cuba, the phenomenon has struck particularly hard in the eastern regions, especially in Guantánamo province. As reported by the newspaper Venceremos, in Baitiquirí Bay—one of the most severely affected areas—decaying macroalgae emit foul odors and have caused ailments such as headaches and nausea among residents.

Local authorities have conducted public hearings and continue to actively investigate in nearby communities. Iroel Cantillo Cartaya, a specialist at the Ministry of Science, Technology, and Environment (CITMA) in San Antonio del Sur, explained that the phenomenon is linked to climate change, which has increased sea temperatures and altered ocean currents, thus promoting sargassum proliferation.

Although a reduction in sargassum accumulation is anticipated starting in July, CITMA has admitted to lacking the technical resources needed to remove the massive concentrations in areas like Baitiquirí, where intervention is unfeasible due to its scale. In other Guantanamo beaches such as Sabanalamar, El Guanal, Los Siguatos, and Yateritas, partial clean-ups are planned before summer. Nevertheless, managing sargassum remains a challenge at the municipal level due to the absence of technology for its final disposal or utilization.

Authorities advise against swimming or walking in areas with high algae concentrations, avoiding direct contact, not consuming fish caught near these zones, and using face masks as a protective measure against the gases. In Cuba, the Civil Defense has now categorized sargassum as a potential risk under its Directive 1 for disaster reduction, considering the complex impacts on public health, local economies, and coastal environments.

Impact of Sargassum on Cuban Beaches

What is causing the increase in sargassum in the Caribbean?

The increase in sargassum is attributed to climate change, which has raised sea temperatures and altered ocean currents, fostering the growth of these algae.

How does sargassum affect marine ecosystems?

Sargassum blocks sunlight, suffocating coral reefs and seagrass beds, and kills the organisms it transports to the shore. It also releases toxic gases harmful to marine life and humans.

What measures are being taken in Cuba to address the sargassum issue?

In Cuba, local authorities are conducting public hearings and investigations, planning partial clean-ups, and advising residents on safety precautions against the harmful effects of sargassum.

© CubaHeadlines 2025