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Sargassum is once again drifting toward South Florida's beaches. Patches of the thick seaweed have a combined weight of more than 6 1/2 metric tons. That's a lot of seaweed. Researchers are trying to predict which beaches it could hit. Tom Bayles of member station WGCU in Fort Myers reports.
TOM BAYLES, BYLINE: Marshall Washington runs the Ron Jon Surf Shop in Key West. He remembers last year's sargassum onslaught.
MARSHALL WASHINGTON: It sucked. It was terrible. It was terrible.
BAYLES: The seaweed was part of the Great Atlantic Sargassum Belt. It's the largest algae bloom in the world. Last year, it weighed 13 million tons and posed challenges throughout the Caribbean and South Florida. And once ashore, it smells like rotten eggs.
WASHINGTON: There were times where it was really bad - piles of about at least a foot and a half. The main beaches were hit pretty hard certain days where they were pretty much like nobody going to them.
BAYLES: For centuries, the huge mats of algae have swirled around the Sargasso Sea in the middle of the tropical Atlantic. In recent years, masses of sargassum broke loose in the spring and floated toward the beaches of Florida and the Caribbean. But Brian Barnes of the University of South Florida's Sargassum Watch System says don't cancel your vacation. It's not like snow.
BRIAN BARNES: The Great Atlantic Sargassum Belt - it's not just one contiguous mass that's going to come and swallow the entire Caribbean and Florida.
BAYLES: But it can bury your favorite beach. To get a heads-up, Barnes is working on a tracking system that uses satellite data.
BARNES: We can identify the sargassum, know where the water is moving, and that's where the sargassum will be moving, and make some predictions on which beaches will be impacted.
BAYLES: It's not an exact science yet. Barnes is part of a team of researchers that have a $3 million federal grant to better forecast which beach the sargassum is going to foul. While still at sea, sargassum mats are safe harbor for lots of little sea creatures, says Barry Rosen, an algae expert at Florida Gulf Coast University.
BARRY ROSEN: It is a mass of living organisms pumping oxygen into the air. It's a very nice ecosystem, and it typically doesn't cause a problem.
BAYLES: Until it comes ashore.
ROSEN: It can impact sea turtle nesting because it can smother the beach. So yeah, it's become a big nuisance.
BAYLES: Researchers predict the return of sargassum to southeast Florida in late May. Marshall Washington at the Ron Jon Surf Shop in Key West is not happy about that.
WASHINGTON: It was just not cool, not good at all. I'm not looking forward to this year.
BAYLES: Neither are the cleanup crews in the Caribbean that are prepared to once again rake up thousands of pounds of seaweed every day it washes ashore.
For NPR News, I'm Tom Bayles in Fort Myers. Transcript provided by NPR, Copyright NPR.
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