Seaweed in Cancun

Update (March 2018): Due to an increased seasonal bloom and on-shore trade winds, several of the beaches south of Cancun to the Tulum area are experiencing an inflow of Sargassum seaweed. This natural occurrence happens in the Atlantic Ocean and Caribbean Sea, impacting islands throughout the Caribbean and the eastern coastline of the Yucatan, when such conditions align.  While the seaweed does accumulate on the beaches near the shore, hotels and villas in the region have jumped into action. Impacted beaches are cleaned each morning with bulldozers and tractors to ensure sandy beaches for visitors. In other protected coastal zones, such as Tulum, hotels and local authorities are implementing manual clean-ups daily to preserve the beach environment.  

Cancun, Playa del Carmen, Tulum and the entire Riviera Maya are known for crystal clear, warm waters and white, sandy beaches. However, on and off for the past 4 years travelers have been experiencing a few days over the course of a week where the seaweed in the water between Cancun and Tulum is pretty significant.

I have done some research and have spend a LOT of time speaking with hotels and other travel experts on the ground in Mexico. It sounds like this is an unusual invasion of Saargassum Seaweed, and the amount really varies by location and can vary even from day to day. This is unprecedented in recent history with no rhyme or reason to it!

seaweed in cancun

I get asked a lot about the Cancun seaweed situation, so I wanted to create a resource that I could update regularly to keep you up to date and help manage expectations with regards to seaweed on the beach in Cancun. Here is a but more detail on the Sargassum Seaweed that is affecting Mexico’s beaches.

What Causes the Seaweed in Cancun?

All across the Caribbean, massive amounts of a viney brown seaweed known as Sargassum washed up and buried beaches. Some of these piles were several feet high during mid-2015! The piles of seaweed grew more than four feet high in Antigua and forced some people to abandon their homes. As the problem reached it’s peak towards the end of 2015, the government of Quintana Roo Mexico hired 5,000 day laborers in four-hour shifts to rake seaweed from more than 100 miles of beaches.

seaweed in cancun

Scientists don’t really know what caused the massive influx of the Sargassum seaweed last year. Scientists have reported that there were 12,300 square miles of sargassum this July 2015, about the size of Maryland, compared with 2,300 square miles four years earlier.

Possible causes have been identified as that generate this phenomenon are:

  • Changing climate (global warming) and new wind patterns that are blowing the seaweed to the coast,
  • Nutrient rich waters producing more sargassum,
  • When there are periods of low hurricane activity, the natural process of being “chopped up” by storms is lessened so we just have more seaweed is floating around.

If there is seaweed Cancun will there be seaweed in Playa del Carmen?

Along the most popular Cancun tourist beaches and the island of Isla Mujeres, the sargassum has mostly been cleaned up thanks in part to a massive undertaking to remove the seaweed but also because the amount of seaweed washing up on shore has mostly gone back to “normal” levels. But farther south along the Riviera Maya, the seaweed took a bit longer to clean up.

Overall the situation is variable. One week there may be large mounds of seaweed heaped on the beaches in one spot, while others the beaches are perfectly clean.

The sea weed accumulation has been most prolific on the stretches of exposed beach and less noticeable in areas that are protected by natural headlands, bays, or coves.  For example, Akumal stayed relatively clean throughout 2015. The highest accumulations throughout 2105 seemed to be in Tulúm.

What is the Current Seaweed in Cancun?

To keep on top of the current seaweed conditions in Cancun, check out this website Nasa and Texas A&M have developed that gives advanced predictions of the floating mats of seaweed. It is called the SEAS project which stands for “Sargassum Early Advisory System”. Go to the forecast section and look for Yucatan Passage 18 for the forecast for the Riviera Maya.

So this is the latest information available on the seaweed issue cancun is facing today.