Huge mats of sargassum seaweed are once again floating towards the Caribbean, with the first signs appearing along major coastlines in early January – weeks ahead of typical seasonal trends.
The first Predictions for 2026 released by the The University of South Florida Optical Oceanography Laboratory warn about one potentially important flowering yearwith preliminary satellite data showing above-average sargassum concentrations in the central Atlantic Ocean, a known precursor to large inflows in the Caribbean Sea.
“We observe early accumulations, especially along the east coast of Barbados, Dominica and parts of the French Antilles,” said dr. Mengqiu Wang, a USF team oceanographer who is monitoring the bloom through satellite images. “Transport patterns from the central Atlantic point to increased arrivals in the first quarter of 2026.”
Reports from Tulum and other parts of the Mexican Caribbean
Visitors to Tulum have already posted photos of arrivals with tall sargassums in our Traveling Lifestyle FB Group: Mexico Sargassum seaweed updates (Cancun, PDC, Tulum, etc.)
Another traveler posted a photo of the early arrival of sargasum in the Dominican Republic on January 8 on Bavaro beach.
2026 could reflect record years
Although it is still early in the season, ocean scientists are warning about the current trends resemble heavy sargassum bloom years such as 2018 and 2022when tons of brown macroalgae flooded beaches from Mexico to Martinique.
According to the latest bulletin of the Caribbean Coastal Ocean Observing System (CARICOOS), Sea surface temperatures remain warmer than normalwhich provides ideal conditions for the growth and drift of sargassum. These warm waters, combined with the supply of nutrients from upwelling and river discharge in West Africa, contribute to the explosive development of algae in the tropical Atlantic Ocean.
Tourism and fishing on alert
Local governments and tourism stakeholders are already alert. In Barbados, cleanup crews have been deployed ahead of the typical peak season in March to deal with new sargassum arrivals. Meanwhile, fishermen in Saint Lucia are reporting difficulty navigating the mats near traditional fishing grounds.
“We had to cut through the sargassum to get to our traps,” said Levi Joseph, a fisherman from Vieux Fort. “It’s not thick yet, but it is worrying this early in the year.”
By 2022, cleanup costs across the region were in the millions, and marine habitats suffered from oxygen depletion caused by decomposing sargassum. A Report of the United Nations Environment Program (UNEP). highlighted how persistent sargassum blooms have disrupted ecosystems, economies and human health.
Experts fear similar patterns could emerge if the 2026 season continues on its current trajectory.
Outlook remains cautious
While scientists emphasize that the The full extent of the 2026 bloom remains uncertainEarly indicators show that Caribbean countries may need to prepare for a longer-than-average sargassum season. Mitigation strategies, including mechanical removal, maritime barriers and offshore harvesting initiatives, are being reevaluated across the region.
Supervisory bodies, including NOAAare expected to release updated forecasts in February, which will provide a clearer picture of expected spring and summer landings.
“This is a regional challenge that requires continued collaboration and adaptive management,” said Dr. Wang. “But these types of early warnings are crucial to give communities time to prepare.”
