Governments and businesses are scrambling to clear shorelines and intercept the floating algae before it devastates vital tourism economies.
Hundreds of hotel workers, tractor operators, and specialized Navy personnel head out to the beach each dawn to clear foul-smelling algae from popular tourist resorts. The seasonal crisis has forced hotels across the region to cut room rates and spend millions of dollars removing seaweed from their coastlines.
In Mexico, sales fell 30% in the first half of the year in the tourism-dependent state of Quintana Roo, according to local business estimates. Alan Vázquez, a waiter in Playa del Carmen, watched customers vanish as decomposing algae turned famed turquoise waters black. He fears the same fate as four colleagues laid off two months prior.
Record Seaweed Volumes and the Great Atlantic Belt
The University of South Florida’s Optical Oceanography Lab recorded 27 million metric tons of self-sustaining sargassum across the Atlantic, Caribbean, and Gulf of Mexico in July, according to a report released by the lab. Scientists observed sargassum growing in large quantities locally in the Caribbean and Gulf for the first time, rather than relying solely on ocean currents to sweep it in from Western Africa.
The Great Atlantic Sargassum Belt has expanded since 2011, fueled by agricultural runoff, warming ocean waters, and shifting wind, rain, and current patterns. Researchers note that the 2025 bloom reached a staggering 40 million metric tons, leaving enough residual biomass behind to spark a new local bloom.
“The 2025 bloom was so big it never really left. It was enough to start a new bloom locally.”
Brian Barnes, marine scientist and research assistant professor at the University of South Florida
Scientists expect 2026 to rank as the second-largest year on record for sargassum abundance. June alone saw 34 million metric tons across the region, a figure only 10% lower than the year-earlier period.
Mexico’s $115 Million Response and Interception Strategy
To combat the environmental and economic threat, Mexico plans to invest $115 million in equipment and cleanup operations. On the worst days, up to 9,000 tons of seaweed hit Mexico’s Caribbean coast, while existing resources allow the government to gather only 1,200 tons daily.
State and federal officials emphasize that waiting for the algae to land is no longer sustainable.
“Experience has taught us the best way to face sargassum is to intercept it in the sea before it hits our coasts.”
Mara Lezama, Governor of Quintana Roo
Federal authorities expect a new open-sea vessel to arrive within a month, while actively sourcing additional ships from Japan and supplying smaller Mexican-made vessels to the Dominican Republic. Data from the government shows that Mexico has collected 96,151 metric tons this year, compared to 92,783 tons during the same period last year.
Collateral Damage to Marine Ecosystems and Coastal Habitats
While open-ocean patches of sargassum provide vital oasis habitats for sea turtles, fish, and seabirds, the massive influx near coastlines creates severe ecological hazards. As the seaweed accumulates in shallow waters, it depletes oxygen levels, smothers mangrove roots, and blocks sunlight from reaching coral reefs and seagrass meadows.
Once ashore, thick mats of algae prevent newly hatched sea turtles from reaching the ocean. Heavy machinery deployed to clear beaches risks destroying fragile turtle nests. In the U.S. Virgin Islands, environmental consultant Amy Dempsey reported that beachgoers must walk up to 25 feet across dense seaweed mats before reaching open water.
Puerto Rico faces similar devastation, prompting a state of emergency declaration from the governor after record masses blanketed tourist hubs like La Parguera. Natural Resources Secretary Waldemar Quiles noted the unprecedented scale of the crisis.
“I don’t recall ever having that much concentration in so many places at once.”
Waldemar Quiles, Natural Resources Secretary of Puerto Rico
Environmental sociologist Emmanuel Maldonado González of East Carolina University underscored the permanence of the threat, calling it a growing hazard rather than a one-off event.
Entrepreneurs Pursue Biofuels, Fertilizers, and Commercial Products
The staggering abundance of seaweed has spurred entrepreneurial ventures seeking to convert the algae into commercial commodities, though removing absorbed toxic metals remains a significant technical challenge. Environment Minister Alicia Barcena reported that out of nearly 200 proposed projects in Mexico, at least 11 hold industrial scaling potential and 39 are actively producing goods.
Existing commercial efforts include manufacturing fuel, agricultural fertilizers, laminates, bioplastics, and craft sandals. Sargassum refiner Carbonwave secured regulatory approval from Mexico’s sanitary watchdog to sell its fertilizers to domestic farmers, while also supplying materials to the cosmetic and textile industries. Meanwhile, Quintana Roo state authorities plan to expand a biofuel facility in Cancun.
Some private operators have explored sinking baled sargassum—which releases methane as it rots—to the ocean floor to generate carbon credits. However, marine experts warn against potential over-harvesting. Brian Barnes cautioned that aggressive offshore clearing could devastate marine life dependent on floating mats, warning that sweeping the Caribbean clean would cause collateral damage.
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