Beach Blanket

A seaweed invasion has Caribbean beaches covered in stinky, rotting piles.

November 04, 2015

News reports of seaweed on the beach sound a bit strange, but right now, the Caribbean is dealing with more than a bit of sargassum seaweed. Scientists estimate that in July, about 12,300 square miles of it—an area roughly the size of Maryland—drifted into the Caribbean. So much of this floating brown algae has been washing ashore that beaches are positively blanketed in stinky, rotting piles that are more than a few feet deep. Desperate not to lose tourists to the invasion, Mexico alone has shelled out over $9 million on a cleanup effort this year and deployed its navy to track the bloom. 

Transported by ocean currents, sargassum drifts into the Caribbean seasonally, but for mysterious reasons—possibly climate change, the Washington Post reports, possibly runoff from farms—a lot more of it has been turning up in the past few years. In small amounts, sargassum can provide shelter for some marine life like baby sea turtles. In current doses, it can entangle animals, preventing them from reaching the surface for air, and even deoxygenate ocean waters, creating dead zones. Ick.

onEarth provides reporting and analysis about environmental science, policy, and culture. All opinions expressed are those of the authors and do not necessarily reflect the policies or positions of NRDC. Learn more or follow us on Facebook and Twitter.

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