An attack of rotting seaweed that blighting many of Mexico's pristine white sand beaches on its Caribbean coast is believed to be the result of climate change.
Sargassum mouths that smell of rat eggs and become clear seawater brown have washed up on the coasts of popular tourist destinations, including Cancun, Playa del Carman and Tulum.
Mexico has already spent $ 17m (£ 13.4m) so far this year in an effort to clear 500,000 tonnes of the plant from its shoreline, but these efforts prove in vain.
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During the last decade, sargassum has flourished over the Caribbean. Scientists believe this is the result of rising sea temperatures and agricultural fertilizers and untreated wastewater that flows into the Caribbean Sea.
Chuanmin Hu, professor of oceanography at South Florida University's College of Marine Science, said: "Due to global climate change we may have increased uplift, increased air deposition or increased nutrient source from rivers so that all three may have increased the latest large quantities of sargasum. "
Mens small amounts of seaweed on beaches are considered beneficial and provide habitats for bird and marine species, too much of it increases sea acidity and temper atur and reduces oxygen. Sargassum is also toxic to some coral reefs, local fauna and fish.
The pristine beaches of the Riviera Maya coast, which make up half of the country's tourism revenue, are now covered by seaweed.
The infestation was first reported in 2014 and has worsened every year since. The tourist manager fears that this can have a serious impact on the local industry as the hotel occupancy begins to fall.
Last month, the Quintana Roo government declared an emergency over the problem describing it as an "imminent natural disaster".
But Mexico's President Andrés Manuel López Obrador said the seaweed was a "minor problem" at a press conference in Cancun on Monday. He said he was not worried about causing more damage to the tourist-dependent region.
Before his visit, the residents wrote a letter complaining that the authorities had not recognized the true extent of this "serious situation".
"Most months of the year, our beaches have lost their crystal color and their shades of blue and turquoise green; seagrass and fish die because of the lack of light and oxygen, turtles and coral reefs are also affected," the letter reads according to Turquesa News .
"It produces an acid gas with a rotating egg smell [when it decomposes] which can be harmful to human health."
In recent years, hotels have put the net in the water near the shore to try to keep the sarassum from beaches, while workers remove the pliers already on shore shovels and wheel barrows. But these methods have proved ineffective.
"Fighting sargassum is a task every day," said Cancun Mayor Mara Lezama. "You clean the beaches in the morning, and sometimes you clean them again in the afternoon or at night, and then go back and clean it again."
However, Sargassum is not only a problem for Mexico, with many islands in the Caribbean also affected.
June Soomer, the Secretary General of the Caribbean States, said that the spread of the seaweed "now considered national emergencies" in some Caribbean countries such as Barbados. "We see a great impact on our countries, economically, socially," she added.
Ricardo del Valle, who owns a business in Playa del Carmen, said: "We offer sun and sand, nothing else. That's what we sell.
" And right now we are lurking our tourists. " Additional Agency Reporting