The tropical dream vacation has a stinky enemy: Massive amounts of brown algae are washing up on the beaches of the popular vacation destinations in the Caribbean and the Gulf of Mexico. Strolling in the warm sun often leads between large patches of washed-up seaweed. In order to swim in the clear sea, in some places tourists first have to dare to wade through a floating brown carpet several meters wide.
“This year, the brown algae appeared earlier than usual,” says Mexican Magda Bremstaller, who lives in Cancún, of the German Press Agency. “Sometimes there are very few, sometimes there are mountains of algae,” says the 55-year-old, who is married to an Austrian. Special teams clean the beaches with rakes and machines. The big hotels put up barriers in the sea to keep their sections clean. The Mexican Navy intercepts seaweed of the genus Gulf Tang (Sargassum) off the coast. But at some point the sheer mass will become almost impossible to cope with, says Bremstaller.
Not much emerald water left
The outlook for the coming months in the Caribbean and on the US coast is particularly bleak. “There are already indications that this year’s brown algae bloom will likely be the largest on record,” predicted oceanographers from the University of South Florida, who have been measuring the spread of brown algae since 2011. There is usually much more algae in the warm months than in the winter.
Penny Dyer hasn’t seen much emerald water from the balcony of her home on Jamaica’s north coast lately. Instead, dark shadows of algae can be seen more and more often. “This is new,” says Dyer of the German Press Agency. The 81-year-old lives in the small town of Oracabessa. After all, the people there consider themselves lucky not to get too much of the algae plague that causes trouble elsewhere. Algae sometimes wash up in Oracabessa, as local anglers tell us. The beaches would have to be cleaned about twice a year. Much more often, however, the current carries them to nearby sections of the coast near Port Maria. If you drive by there, you have to hold your nose because of the stench, says 52-year-old deep-sea fisherman Milton Cole.
Just under ten percent of the monitored locations were free of brown algae
Ocean currents and winds could change the situation in a given location from one day to the next, says Mexican biologist Esteban Amaro. He heads the “Red de Monitoreo del Sargazo de Quintana Roo” monitoring initiative, which publishes a map of the current situation on around 100 beaches in the Mexican region on Facebook. Only just under ten percent of the monitored locations were free of brown algae at the beginning of April.
According to the University of South Florida, around 13 tons of the free-swimming brown algae drifted from the central Atlantic towards the Caribbean Sea in late March – a record amount for that period. The peak of flowering is expected in June or July. It is difficult to predict when and where the algae will later be washed ashore.
Those who want to travel inform themselves about the best travel destinations in Facebook groups and forums so that the brown algae don’t spoil their vacation. Shortly before their arrival, others want to know what the situation is like in Barbados or Florida. Vacationers share photos and videos of the current situation in the groups. Some celebrate the currently clear water: “Very nice today.” The others complain about the brown sea: “I’ve never seen anything like it.”
Research into the causes: What are the triggers?
On the open sea, brown algae contribute to the health of the sea. But when they decompose on the shore, the algae smell like rotten eggs and are harmful to the environment. Seagrasses are dying, mangroves are drying up and baby sea turtles are getting stuck en route to the ocean after hatching. So much organic material on the coast could forever change the turquoise color of the sea and the white beaches of the Caribbean, said Mexico-based Dutch biologist Brigitta van Tussenbroek at a forum.
Researchers continue to look for possible triggers. Deforestation in the Amazon? Higher sea temperatures? Excess nutrients from human activities spilling into the Atlantic from rivers in Africa and South America? Possibly, they say. According to studies, however, one weather phenomenon could have been decisive: the North Atlantic Oscillation (NOA).
In the winter of 2009-2010, there was an unusual change in wind patterns in the North Atlantic, US researchers reported. This caused the brown algae to spread from the Sargasso Sea east of Florida, where it has always existed. The winds and currents then carried them south along the African coast to the tropical Atlantic. There the brown algae found favorable conditions for their explosive spread: plenty of sunlight, warm water temperatures and nutrients.
Tourists are not deterred
For regions that live almost exclusively from tourism, their image as a tourist destination is fundamental. Tourists in Quintana Roo, Mexico, have not been put off by the algae and are arriving in increasing numbers, official statistics show.
“We have to preserve the natural resources in order to continue to attract tourism,” says the biologist Amaro. After all, the Mexican Caribbean markets postcards of turquoise waters, incredible beaches and jungles. “We must take care of the goose that lays the golden eggs”.
