It is natural for seaweed to wash up on the beach from season to season, after storms and in the summer heat. However, this summer larger quantities of two species of seaweed known as Gulfweed or Sargassum (Sargassum natans and Sargassum fluitans) are coming ashore from time to time in the Riviera Maya, Cancun and other parts of the Mexican Caribbean. These landings occur periodically, the amount of seaweed varies and not all beaches are affected.
Similar landings are occurring in the Caribbean islands and along the Gulf coast of the United States.
The word Sargassum comes from the Portuguese word sargaço, which means “little grapes,” a reference to the air-filled bladders that enables it to float on the surface and move with the currents. Unlike other algae that are rooted in the seabed or attached to rocks or corals, pelagic or free floating sargassum grows and reproduces as it drifts through the water.
Pelagic Sargassum seaweed is historically associated with the Sargasso Sea in the North Atlantic Ocean where vast beds of it are a habitat for marine life such as microscopic plants, shrimp, crabs, sea horses, baby fish and turtles.
Sometimes ocean currents transport lines or patches of this seaweed to areas beyond the Sargasso Sea. However, biologists believe that the Sargassum affecting the Caribbean islands and the coast of Quintana Roo may have a different source, an area off the coast of northern Brazil, thousands of kilometers away. The causes of the seaweed proliferation or bloom have been attributed to rising sea temperatures due to global warming and excessive nutrients in the water flowing into the sea from the Amazon River and its many tributaries. The appearance of drifting mats of sargassum where they were previously very rare may also be linked to variations in currents and wind patterns.
Beach cleaning in Quintana Roo
A statewide campaign is underway to track the movement of patches of drifting sargassum and to collect and dispose of the seaweed when it comes ashore on public beaches in different parts of the Mexican Caribbean. The Mexican government pledged additional funds for beach cleaning during the summer. Many hotels and resorts have their own cleaning programs and there are volunteer beach cleaning initiatives too.
Based on the recommendations of marine scientists, the authorities are now implementing a second phase of the program to prevent the sargassum from coming ashore by installing barriers in the sea. The first barrier will be installed in the Punta Nizuc area in the coming days and will be followed by additional barriers in Tulum and Playa del Carmen, Mahahual and Puerto Morelos.
The barriers are anchored to the seabed but float on the surface of the water perpendicular to the coast. Each one is 30 meters long and they can be connected to form a chain. They will be installed in areas where sargassum landings are the most frequent, taking into account the circulation of ocean currents and wind direction. They do not trap the sargassum but are designed to deflect it so that the currents move it away from the shoreline.
The barriers will not impede the movement of marine creatures nor trap them, affect coral reefs or the sea grass beds and they can be dismantled as the sargassum diminishes with the arrival of cooler temperatures in September and October.
In Puerto Morelos, the local authorities are also collecting the seaweed in a boat before it reaches the shallows.
Royal Resorts
Beach cleaning has been redoubled at the Royal Resorts in Cancun in recent weeks. It is taking place at night and in the morning. The local authorities are permitting the use of a tractor at this time as long as it is on wet sand in the zone where the waves break. An additional cleaning brigade was brought in at The Royal Sands, The Royal Caribbean and The Royal Islander for June, July and August.
Cleaning has also been stepped up at The Royal Cancun although seaweed landings principally affect the stretch of Cancun shoreline from Punta Cancun to Punta Nizuc that faces the open ocean.
Grand Residences by Royal Resorts
At Grand Residences by Royal Resorts to the south of Puerto Morelos, a mechanized beach sweeper operates twice a day. If needed, the resort’s team of gardeners is on call to offer additional support.
The Royal Haciendas
The Royal Haciendas is doing its best to keep the beach clean with volunteers and an external team that has been hired by the resort for this duty. With additional personnel and the use of the tractor, the aim is for a more efficient removal process, however sometimes more seaweed comes ashore later in the day.
Turtle nesting season
It is turtle nesting season and in the Riviera Maya government beach cleaning regulations prohibit the use of heavy machinery on dry sand to prevent it from compacting or causing irreversible damage to turtle nests and eggs. This means that at The Royal Haciendas the tractor can only be used on the shoreline where the waves break and at certain times of the day.
All along the coast, turtle patrols are keeping an eye on adult turtles coming ashore to nest on beaches at times when there are seaweed landings. They will also watch over the hatchlings as they are born later in the season to ensure that they do not become entangled in it.
Swimming tips
Seaweed washes up on the beach naturally and is an important habitat for marine life. The presence of seaweed does not mean that beaches are polluted. You can still swim in the sea.
Showering after swimming is recommended and swimsuits should be rinsed out after use. Seaweed will not sting you. However, microscopic creatures or insects may be trapped in the weed and can occasionally irritate the skin, hence the recommendation to rinse off after sea bathing.