Giant swarms of kelp could soon settle along beaches in Florida and across the Gulf of Mexico, scientists warn, polluting popular tourist destinations for months.
Seaweeds, a type of leafy, floating algae called sargassum, typically spend most of the year oscillating in a 5,000-mile-wide mass across the Atlantic Ocean. Sargassum is generally useful at sea, providing food and breeding grounds for a variety of species, including fish, sea turtles, and seabirds.
The real danger of the Sargassum comes when it is washed ashore. Seaweed begins to rot after a few days on land, releasing hydrogen sulfide gas that smells like rotten eggs and leaving behind a brown sludge that can contaminate beaches for weeks. Hydrogen sulfide can threaten human health, and the sheer amount of seaweed could be too much for local crews.
Parts of Mexico’s Yucatán Peninsula were covered with about 200 tons of sargassum in early March, prompting warnings of “excessive” algae levels near the popular Playa del Carmen. Officials have warned that some beaches are at risk of up to 3 feet of seaweed a week, with no signs of sargassum decreasing as summer approaches.
Media outlets in Key West also reported that the Sargasso floods hit much earlier than usual last week.
Past blooms have caused a state of emergency in the Virgin Islands and polluted islands across the Caribbean, and they’re only getting bigger every year.
Scientists first noticed supercharged seaweed rafts in 2011. Some researchers have suggested that they may be getting bigger as fertilizer and agricultural waste run off into the ocean in large quantities.
“These flowers are getting bigger and bigger, and this year looks set to be the biggest on record,” Brian Lapointe, research professor at Florida Atlantic University, told The New York Times. “It’s pretty early to see so much, so soon.”
Large areas of sargassum are currently floating in the northern Caribbean and near the east of Mexico’s Yucatan Peninsula.
The University of South Florida, which tracks annual seaweed blooms, predicts 2023 will be a “big” year for sargassum, disrupting tourist plans and endangering coastal ecosystems.
Scientists said they expect the Sargassum disaster to become the new normal.
