The 2026 sargassum seaweed season in the Mexican Caribbean began unusually early. If previously the massive appearance of algae was expected closer to April or May, then this year the first large emissions began to be recorded in January. For guests of the public sector, this becomes a disaster: algae on the beaches ceases to be a «seasonal nuisance» and become a permanent feature of the region.
Today, algae is present to some degree on almost all the beaches of Mexico's Caribbean coast, from Cancun to Mahahual. But this does not mean that all beaches look equally bad. In some places the algae lies like a dense brown-brown carpet, but in others visitors hardly notice them.
Social networks create a feeling of total disaster. One video of a seaweed-choked beach in Tulum quickly gives the impression that the entire Mexican Caribbean is uninhabitable. But the situation is more complex and dynamic.
Clean where they clean. Algae-free beaches — this is most often the result of constant cleaning rather than the absence of algae. The hotels themselves, especially large ones, clean the beaches most actively. Many of them begin cleaning before dawn. Tractors and manual crews work on the beaches, and in the sea — special nets and barriers. It is for this reason that guests of the country often see a paradoxical picture: near one hotel the beach is almost perfect, but after 300 meters — a thick layer of algae with a characteristic odor.
The worst situation with algae is on wild beaches and in places without regular cleaning. According to Red de Monitoreo de Quintana Roo, the most difficult algae situation is now observed in Tulum, in Mahahual, on selected beaches in Playa del Carmen, on the east coast of Cozumel, in the southern part of the Riviera Maya. It is there that ocean currents bring the bulk of algae.
At the same time, Cancun, Isla Mujeres and Holbox look much better. This is especially true of Cancun's northern beaches, where currents and shoreline configurations help keep the water relatively clear.
De acuerdo con las simulaciones más recientes, Quintana Roo podría registrar este año un incremento de entre 30 y 40 por ciento en el arribo de sargazo respecto a temporadas anteriores.
El especialista explicó que mayo, junio y julio representan el período más crítico, mientras…pic.twitter.com/DfHZTwi3TQ— WaldoAPN (@Waldo_APN)May 22, 2026
Some beaches can remain almost perfect for several days in a row, and then literally overnight become covered with a layer of algae when the wind changes direction.
Sargassum algae, or Sargassum — this is not «dirt» and not pollution in the usual sense. These are floating brown algae that historically existed in the Atlantic as a separate marine ecosystem. They are even called "floating forest": in the open ocean they serve as a refuge for fish, crabs and sea turtles.
The problem is different — Over the past 10-15 years, the number of such algae in the Atlantic has increased dramatically. Scientists attribute this to several factors: climate change, rising ocean surface temperatures, increasing amounts of nutrients in the ocean, fertilizer runoff through large rivers in South America, and changes in ocean currents.
Now huge masses of algae are drifting across the Atlantic from the coast of Africa to the Caribbean, covering thousands of kilometers. According to environmentalists, more than 120 thousand tons of algae could wash up on the shores of the Mexican Caribbean Sea in 2026 (although more than 90 thousand tons had already been collected as of mid-May). This is significantly more than last year's figures and almost a record.
Fresh algae in the sea usually has almost no smell. An unpleasant odor appears after they begin to decompose on the shore. When decomposed, hydrogen sulfide is released, the same rotten egg smell that is sometimes felt on the beaches of the Mayan Riviera in the summer. That is why hotels try to remove algae as quickly as possible, sometimes literally within a few hours after washing ashore.
CRISIS EN PLAYA DEL CARMEN 🚨🌊
Las barreras de contención fueron totalmente sobrepasadas este fin de semana por la llegada masiva de sargazo a las costas. El alga desbordó las protecciones e inundó las playas.
#Sargazo#PlayaDelCarmen#QuintanaRoopic.twitter.com/PcpFcGf6IL
— Código MX (@CdigoMXdigital)May 19, 2026
An important point that travelers often do not understand: algae does not arrive on beaches at the same rate all summer. They usually come in waves. The beaches may look great for a few days, then the current comes and the situation changes dramatically. Then the wind clears the coastal water again. For this reason, photos from the Internet quickly become outdated. A video from a week ago does not always reflect the current situation, especially on a particular beach. That is why local authorities and environmental services publish daily «Sargassum traffic lights» with the current state of the beaches.
But despite barriers, ships, tractors and daily beach cleaning, it is impossible to completely stop the algae. The scale of the phenomenon is too large. The problem is complicated by the length of the coastline of the state of Quintana Roo — there are hundreds of kilometers of beaches. As a result, the main efforts are concentrated in tourist areas and near expensive hotels.
But even during the algae season, a vacation in Cancun, Playa del Carmen or Tulum can be quite comfortable if you choose good hotels with active cleaning, do not rely only on viral videos from social networks, monitor the daily situation on the beaches, and understand that the state of the sea changes literally every day.
In 2026, algae is indeed present almost everywhere. But between the «algae there» and «swimming is not allowed» — huge difference.