Heavy Sargassum Expected in 2026
USVI Division of Fish and Wildlife warns of a likely major sargassum year in 2026 after satellite data showed sharp increases in late 2025. BVI residents should prepare for beaching events, health irritants from decomposing seaweed, and potential impacts to tourism and boating.
Virgin Islands Department of Planning and Natural Resources (DPNR) has warned that 2026 is likely to be another major sargassum year after satellite observations in December 2025 showed sharp increases in sargassum across the Eastern Caribbean and western Atlantic. The forecast, developed with the University of South Florida College of Marine Science and supported by NOAA's Monitoring and Event Response for Harmful Algal Blooms program, found sargassum abundance across the Atlantic more than 75 percent above historical averages and identified two large algal masses that may drive continued beaching.
The rapid growth from November to December and observed early beaching in parts of the region increase the chance that the British Virgin Islands will see significant accumulations in the coming months. Since 2011, recurring large blooms originating near the Amazon River have sent extensive sargassum mats across Caribbean shorelines, and this latest analysis indicates the trend may continue or intensify in 2026.
For BVI residents, impacts will be both environmental and practical. Fresh sargassum at sea is not generally harmful to swimmers, but floating mats can conceal jellyfish and other stingers. Once ashore, decomposing sargassum releases hydrogen sulfide, which smells like rotten eggs and can irritate the eyes, nose, throat and lungs — a particular concern for people with asthma or other respiratory conditions.
Large clumps also pose navigational hazards by fouling propellers and cooling intakes on motorised vessels. Officials recommend avoiding beaches with large amounts of decaying sargassum to reduce exposure. Boat operators encountering tangled sargassum are advised to place the motor in reverse to clear propellers.
Small-scale beach removal can be done by hand or with rakes, but residents and beachfront businesses should consult local authorities before large-scale mechanical removal to ensure environmental protections and proper disposal. In the USVI, DPNR and its Division of Fish and Wildlife issue permits for mechanical cleanup and offer training on ecological best practices; containment booms require a separate U.S.
BVI communities should monitor communications from local environmental and marine agencies, liaise with waste management and tourism operators, and consider similar preparedness and training measures. Sargassum also plays a role as marine habitat, but large accumulations on shore can harm local tourism and fisheries if not managed carefully.
Residents and business owners are encouraged to stay informed through regional forecasts from the University of South Florida, NOAA updates, and any local advisories so steps can be taken early to protect health, infrastructure and livelihoods.
Primary source: VINO