HomeOutdoorsNewsBlob of Seaweed Twice the Size of US Threatens Florida

Blob of Seaweed Twice the Size of US Threatens Florida

by Caitlin Berard
Sargassum Seaweed, Species Threatening to Choke Florida Beaches
(Photo by Artur Widak/NurPhoto via Getty Images)

Deep in the Atlantic Ocean, there lies a 5,000-mile-wide raft of seaweed so large it can be seen from space – and it’s currently making its slow descent on Florida.

Spanning about twice the width of the United States, the thick mat of sargassum blooms floats between the Gulf of Mexico and the coast of West Africa.

Now, out at sea, the living blanket poses little problem. In fact, seaweed is largely beneficial for aquatic ecosystems, providing a habitat for many species of fish and crustaceans and removing massive amounts of carbon dioxide from the atmosphere. As it floats nearer to shore, however, it becomes a much larger issue.

As hundreds of tons of sargassum seaweed wash up on the shores of the Gulf of Mexico and the Caribbean, the wet mat of algae shifts from life-giving to suffocating. The slow invasion chokes coral, diminishes air and water quality as it decomposes, and inflicts tremendous harm on coastal ecosystems.

With a toxic algae bloom and a grisly red tide forcing residents and visitors alike to flee beaches with burning eyes and breathless lungs, the Sunshine State is already having a tough year. The influx of seaweed could make things even worse for Florida.

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

Surge of Seaweed Could Have Devastating Effect on Florida

LaPointe, an expert in seaweed and algae blooms, explained that the effects of the sargassum have already begun. Beaches in the Florida Keys are seeing the beginning of the onslaught of seaweed. Meanwhile, officials warned parts of Mexico to prepare for up to three feet of sargassum to coat its shores.

Obviously, stepping onto a beach expecting white sand and blue seas and instead seeing massive globs of brown plant matter is an undesirable experience. But the seaweed isn’t just unsightly. Hunks of sargassum have the ability to trap boats and other aquatic machinery.

“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,” said marine scientist Brian Barnes. “It can really threaten critical infrastructure.”

As it rots, sargassum seaweed releases hydrogen sulfide, worsening respiratory issues for Florida tourists already struggling to breathe through the pungent scent of the red tide. Back in 2018, a similar situation left thousands hospitalized with breathing complications.

As the USF Optical Oceanography Laboratory reported, these sargassum blooms only appear to grow as the years pass. Thus far, 2018 and 2022 had the largest blooms on record. Scientists suspect, however, that this year’s invasion could be even worse.

“Historically, as far back as we have records, sargassum has been a part of the ecosystem, but the scale now is just so much bigger,” Barnes explained. “What we would have thought was a major bloom five years ago is no longer even a blip.”