The Sargassum seaweed season, which traditionally begins in the spring, showed up earlier than usual in 2026: the first significant accumulations of algae on the beaches of the Caribbean coast of Mexico were recorded in early January. Changes in the dynamics of ocean currents in the Atlantic Ocean in recent years and increased levels of nutrients in the deep waters of the Atlantic contribute to the fact that the season is not only formed earlier, but also develops more intensely than before. «Officially» Algae season on Mexican beaches starts in April.
Personnel of the Mexican Navy (SEMAR), in collaboration with the authorities of the state of Quintana Roo, have already begun active work to collect sargassum seaweed in key resort areas, including Cancun, Isla Mujeres, Playa del Carmen, Cozumel, Puerto Morelos, Tulum, as well as the municipalities of Mahahual and Xcalac.
According to SEMAR, about 178 tons of seaweed have been collected from the sea so far, indicating an early start to the season and high concentrations of seaweed off the coast. On the shore, in the El Recodo area at the resort in Playa del Carmen in early January, a record amount of algae was collected in a short period of time — approximately 1000 tons even before the start of the peak season.
By comparison, for the entire year 2025, the joint efforts of SEMAR, municipalities and private organizations resulted in the collection of 92,783 tons of sargassum along the beaches of Quintana Roo — an indicator that was one of the highest in recent years.
At the same time, the appearance of algae on beaches is not yet a widespread and sustainable phenomenon. For example, in Cancun, due to cold northern winds, their excessive occurrence in the second half of January was recorded only on certain beaches, Playa del Niño and Playa Langosta, while in sandy areas such as Playa Delfines and Coral, the amount remains within the normal range. Although the current volume of seaweed collected on Cancun beaches is about 7 tons per week, this is not technically considered a critical amount.
Sargassum algae in the tropical Atlantic Ocean remains at historically high levels and continues to increase, according to the University of South Florida (USF) Optical Oceanography Laboratory. Satellite images show that the Great Atlantic Sargassum Seaweed Belt, stretching off the coast of West Africa, is moving rapidly towards the Caribbean Sea. Models indicate that sargassum concentrations in the region have the potential to exceed 75% of historical maximum levels. This means that the Caribbean coast of Mexico is capable of acquiring quantities of seaweed comparable to or even higher than those collected during the 2022 season — one of the largest in recent decades.
To reduce the amount of Sargassum seaweed reaching the coast, it is planned to expand the infrastructure of protective barriers and increase efforts to collect seaweed from the sea before it reaches the shore. Experts say the current barrier network of about 9.5 kilometers is insufficient and should be expanded to an additional 6 kilometers or more to improve protection effectiveness.
When large masses of algae are concentrated near the coastline, it causes many negative consequences. The decomposition of algae reduces the oxygen content in the water and harms marine fauna, the quality of the water deteriorates, creates unpleasant odors, and beaches become unsightly in appearance.
The deterioration of the appearance of beaches and difficult access to the sea lead to cancellations of bookings and a decrease in hotel occupancy, companies are forced to significantly increase costs for cleaning beaches, travelers in some cases choose alternative destinations, which leads to a drop in income for tourism operators and restaurants.
According to a study by the Inter-American Development Bank (IDB), sargassum seaweed discharges on Quintana Roo beaches have the potential to reduce travel activity by 17.5%, leading to a drop in gross regional product of approximately 11.6%. The negative effects continue even after the season ends: additional economic losses can range from 5.9% to 9.9% in subsequent months.