Sargassum Blankets Caribbean and Gulf Coasts With 27 Million Tons as Local Blooms Take Hold
Updated
Updated · PBS NewsHour · Aug 1
Sargassum Blankets Caribbean and Gulf Coasts With 27 Million Tons as Local Blooms Take Hold
3 articles · Updated · PBS NewsHour · Aug 1
Summary
27 million metric tons of Sargassum were recorded across the Atlantic, Caribbean and Gulf in July, with scientists saying 2026 is likely the second-largest year on record.
The new concern is local reproduction: researchers said this is the first time large quantities have grown in the Caribbean and Gulf instead of arriving mainly via currents, after 2025's record 40 million-ton bloom never fully disappeared.
Mexico plans to spend $115 million to fight the algae, but says up to 9,000 tons can hit its Caribbean coast on the worst days while current capacity removes only 1,200 tons daily.
Tourism and coastal ecosystems are already taking the hit—Quintana Roo businesses estimate first-half sales fell 30%, while nearshore mats deplete oxygen, smother mangroves and coral, and can block hatchling turtles.
The spread is regional: Puerto Rico and the U.S. Virgin Islands report some of the worst accumulations in years, and Martinique has collected more than 11,500 tons while sheltering residents from toxic gases.
As toxic seaweed chokes the Caribbean in 2026, could this self-sustaining biological nightmare secretly hold the key to a lucrative new industry?
With rotting algae overwhelming cleanup crews, what hidden ecological triggers are making these massive coastal blooms seemingly unstoppable?
Could the very same floating mats that suffocate coastal economies actually be acting as a vital, overlooked shield against global warming?
Record-Breaking Sargassum Blooms in 2026: Ecological, Economic, and Policy Challenges for the Atlantic and Caribbean
Overview
In the summer of 2026, record-breaking volumes of sargassum seaweed inundated the Atlantic, Caribbean, and Gulf of Mexico, causing severe ecological and economic impacts. Massive mats drifted ashore, blocking sunlight and raising water temperatures, which led to oxygen depletion, black tides, and die-offs of marine life. Beaches became buried, harming sea turtles and forcing costly cleanups that risked further environmental damage. The crisis was fueled by climate-driven ocean changes and deep-ocean upwelling, which provided nutrients for rapid sargassum growth. Advanced satellite tracking and new international policies are now being developed to help coastal communities respond to this growing challenge.