Apr 5, 2023 - News

Massive seaweed bloom washing up in South Florida breaks record

A tractor plows seaweed that washed ashore in Fort Lauderdale on March 16, 2023. Photo: Joe Raedle/Getty Images

The big brown seaweed belt in the Atlantic Ocean that's starting to wash ashore in South Florida has grown to a record-breaking 13 million tons.

Why it matters: While sargassum provides critical habitat for marine life, it can also muck up beaches, which can be expensive to remove.

  • Plus, the seaweed emits a gas that smells like rotten eggs, and the sea life that resides within it can cause skin irritation.

What's happening: Miami-Dade County is seeking state funding to help with removal efforts as researchers warn that "more beaching events are inevitable" from the bloom in the coming months.

Zoom in: Miami-Dade has budgeted $4 million to remove seaweed from "hot spots" around Government Cut, Miami Beach from 26th to 32nd streets, Bal Harbour and Haulover Cut.

  • But the county is asking the state Legislature for an extra $2 million to fund seaweed removal if an "overabundance" of sargassum reaches Miami's shores, a county spokesperson tells Axios.

Catch up fast: The sargassum seaweed bloom is an annual phenomenon that engulfs beaches from the Caribbean to the Gulf Coast.

  • The official tally of the bloom in March shattered the previous record quantity for the month — about 9 million tons in 2018, the University of South Florida's Optical Oceanography Lab recently reported.
  • "Although the peak month of June or July is several months away, there is already a sign that this year's sargassum bloom will likely be the largest ever recorded, with major impacts throughout the next few months," the report states.

Between the lines: Sargassum blooms — which became prevalent around 2011 — have been linked to the burning of fossil fuels, deforestation and nutrient runoff.

What they're saying: Brian Barnes, an assistant research professor at USF, tells Axios it's not possible to accurately predict when patches of seaweed will impact specific beaches as winds and currents control its movement, but more seaweed is expected in the coming months.

What we're watching: In a memo this week, Mayor Daniella Levine Cava said Miami-Dade is seeking additional resources and funding from the federal government to address the "potential overabundance of sargassum."

  • She also said the county is exploring greener ways to manage the seaweed, such as composting.

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