a beach covered with sargassum algae

Sargassum blooms like this can cause a plethora of issues for humans and wildlife. Photo: Shutterstock

The Inertia

There’s a giant mass of stinky, salty, intertwined life headed directly for the Florida coast in the coming weeks, a phenomenon that, while once manageable, now threatens the wildlife and economy of the Sunshine State.

No, it isn’t spring breakers. It’s a humongous sargassum bloom spanning roughly 5,000 miles. That’s about twice the width of the United States. Sargassum, as defined by NOAA, is “a genus of large, brown seaweed (a type of algae) that floats in island-like masses and never attaches to the sea floor.”

Well, this mass — one of the largest on record — is headed west, and scientists can see it from space. And as you might imagine, they and Florida residents alike would prefer that not to be the case.

“It’s incredible,” Brian LaPointe, a research professor at Florida Atlantic University’s Harbor Branch Oceanographic Institute, told NBC News. “What we’re seeing in the satellite imagery does not bode well for a clean beach year.”

Florida Seaweed Bloom’s Potential Dangers

When the current bloom makes landfall (it’s already started in the Florida Keys), it will cause a host of issues. There’s a loss of revenue from Florida’s crucial tourist industry and the related infrastructure costs of removing the seaweed from beaches.

But Brian Barnes, an assistant research professor at the University of South Florida’s College of Marine Science, told NBC News the sargassum could be more than a nuisance to beachgoers.

“Even if it’s just out in coastal waters, it can block intake valves for things like power plants or desalination plants, marinas can get completely inundated and boats can’t navigate through,” he said. “It can really threaten critical infrastructure.”

a sargassum bloom on a tropical beach

Sargassum blooms, increasingly large in the last decade, threaten not only tourist economies, but wildlife as well. Photo: Shutterstock

The rotting piles of sargassum can also cause breathing issues, as they did in Martinique and Guadeloupe following a bloom in 2018. And there’s a cost to wildlife that isn’t adapted to handle such extreme amounts of seaweed.

“If there’s anything living on the ocean bottom like a coral or a seagrass…they receive a huge blanket of dead sargassum, they cannot breathe. If you have a turtle or a turtle nest on the beach, you have a huge thick blanket on the turtle nests, the young turtles will have a hard time surviving,” Dr. Chuanmin Hu, professor of Oceanography at the University of South Florida, shared with a Florida NBC affiliate.

Sargassum blooms have been increasing in size and density for over a decade, driven, scientists speculate, by increased nitrogen concentrations pouring into the Atlantic from the world’s major river systems. Where’s it all coming from?

“Deforestation, increased fertilizer use and burning biomass,” according to LaPointe. “All of that is increasing the nitrogen concentrations in these rivers and so we’re now seeing these blooms as kind of a manifestation of the changing nutrient cycles on our planet.”


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