Tourist hotspots along Mexico’s Caribbean coastline, especially in Quintana Roo and the Riviera Maya, are facing a crisis as an unprecedented sargassum seaweed surge blankets beaches from Cancún to Tulum. Satellite observations and official reports signal that the summer of 2025 is shaping up to be the worst sargassum season ever recorded.
Satellite Data Shows Record-Breaking Spread
In May alone, the University of South Florida’s Optical Oceanography Lab detected a staggering 37.5 million metric tons of sargassum floating across the Atlantic basin — the highest quantity since its monitoring began in 2011. Additionally, a giant belt of seaweed stretching thousands of kilometers is expected to bring over 522,000 metric tons of the algae to beaches in Quintana Roo — surpassing the previous record set in 2018.
Local Impact: Beaches Buried, Tourism Threatened
Authorities in Playa del Carmen, Puerto Morelos, Tulum, and Cozumel report extensive seaweed accumulation. In May alone, local cleanup crews collected more than 1,465 tons of sargassum along the Riviera Maya coast. However, even with barriers, barges, and manpower from municipal workers and naval personnel, cleanup efforts are struggling to keep pace .
According to Esteban Amaro of the Sargassum Monitoring Network, levels in 2025 are expected to exceed those of the past three years, with early arrivals signalling a prolonged battle.
Public Health and Environmental Concerns
While sargassum is a natural marine habitat, its decomposition along the shore generates hydrogen sulfide gas that smells like rotten eggs and can cause respiratory and skin irritation. Large beach accumulations also accelerate sand erosion as heavy equipment scrapes away sand just to remove the seaweed .
Authorities Mobilize with Proactive Measures
In response, Quintana Roo’s governor launched a coordinated cleanup campaign in mid-April, deploying nearly 9,500 meters of offshore barriers, a fleet of 11 large navy vessels and 22 smaller boats, plus shoreline crews from municipal teams, state brigades, and marina workers. The Mexican government is closely monitoring close to 48 beaches along the Yucatán to contain sargassum before it hits the coast.
Economic and Tourism Fallout
Tourism, the backbone of the region’s economy, is at risk. Puerto Morelos hotel operators report losing guests, while fishermen in Mahahual have halted operations due to dense seaweed covering fishing grounds. Environmentalists also warn that dumping collected sargassum irresponsibly—into quarries or backwaters—can damage groundwater and ecosystems .
Looking Ahead: June Through October
Experts warn that sargassum landings typically occur from April through October — and in 2025 this window promises to be more severe, possibly extending into November . The severity in any given coastal area will largely depend on ocean currents and wind patterns.
What It Means for Travelers
- Plan ahead: Monitor sargassum forecasts via the University of South Florida and local monitoring networks.
- Choose wisely: Beaches like Isla Mujeres, Isla Contoy, or north-Cancún often experience less sargassum.
- Know your resort: Many hotels have installed offshore barriers or created inland lagoons to offer sargassum-free swimming options.
The Caribbean coast of Mexico is entering an unprecedented sargassum season — the worst yet. Despite heroic cleanup efforts, local ecosystems and economies will feel the impact through at least November. Tourists, residents, and officials alike must brace for the effects of this algal deluge.
For daily updates on beach conditions, sargassum maps, and cleanup progress, consult the Sargassum Monitoring Network and local government advisories.
