Mounds of smelly seaweed return to South Florida beaches amid heat wave

Smelly sargassum seaweed invades Florida beaches

Record-breaking blooms of smelly sargassum seaweed are invading Florida beaches. FOX Weather Correspondent Brandy Campbell was in Dania Beach on July 23 and explains that even though the brown microalgae can be beneficial for marine life, it can become a mess after decomposing on the beach.

DANIA BEACH, Fla. – As Florida grappled with another summer heat wave, unsightly scenes of brown seaweed have once again blanketed parts of the Sunshine State’s coastline.

Photos from Dania Beach, located near Fort Lauderdale, showed the usually white sand Wednesday littered with sargassum. The seaweed emits a sulfur-like odor as it decomposes, producing a smell similar to that of rotten eggs.

A combination of a persistent easterly swell and the right ocean currents likely brought the latest wave of algae to the Florida shore.

This isn’t the first time this year that sargassum has become a nuisance along Florida’s beaches. 

Similar conditions occurred during the spring with notable seaweed build-ups in April and May, focused primarily along the state’s east coast beaches.

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Despite the recent influx, the sargassum affecting Florida is far removed from the record-breaking amounts being monitored in more tropical regions of the Atlantic basin.

According to the University of South Florida’s College of Marine Science Optical Oceanography Lab, much larger blooms remain concentrated in the Caribbean Sea, Gulf of America and Atlantic Ocean near the equator.

In its latest sargassum bulletin, marine experts noted that seaweed coverage across the Gulf and Caribbean had increased in recent weeks, while parts of the Atlantic experienced a decrease when compared to the prior month. 

The lab’s outlook suggested that summer may represent a turning point for sargassum development. Fewer concentrations are expected in the deep tropical regions, with more periodic inundations around the Yucatán, Northwest Caribbean, Bahamas and Florida.

The USF bulletin also cautions that local factors, such as wind direction and ocean currents, ultimately determine where sargassum invades. This makes local predictions difficult.

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While the seaweed might look unpleasant and produce an odor, the Florida Health Department says it is largely harmless to humans.

Tiny creatures that are known to bury in the globs of seaweed can produce rashes and blisters if contact is made with a person’s skin.

For some species of marine life, the brown algae is considered to be helpful, and biologists believe that the buildup provides food and refuge for small fish, crabs, shrimp and other tiny organisms.