A Massive Surge of Smelly Seaweed is Expected on Florida Beaches: Here’s the Scoop

It’s that time of year again, as a huge mass of sargassum seaweed may be Florida-bound.

In the latest forecast for the 2025 sargassum blooms, University of South Florida researchers have reported that the Sargassum levels in the Caribbean and West Atlantic, regions adjacent to Florida, have reached unexpectedly high amounts.

The findings reveal that the sargassum volume in these areas was 200% above their historical averages in April, and 40% higher than the record peak observed in June 2022. What implications does this have?

It means that 2025 has just set a new sargassum record.

“The substantial rise is attributed largely to both local growth and physical movement, however, the specific causes behind these unprecedented records still require further investigation,” the study indicates.

Per the researchers, sargassum has already been reported along the southeast coast of Florida, though even more sargassum is expected to start popping up throughout May.

“Sargassum inundation will continue to occur in most of the Caribbean nations and islands, as well as along the southeast coast of Florida,” the study concludes.

According to the NOAA, sargassum seaweed is a type of brown algae that floats in island-like masses, buoyed by gas-filled “berries” that keep them on the surface of the water.

The huge masses can sometimes stretch for miles over the ocean, providing refuge and food for a variety of sea life.

But while sargassum plays a vital role in these ecosystems, they can cause quite a stink when they wash up on beaches, leaving odors that smell like rotten eggs. This stench is caused by a toxic gas that can be harmful for people with respiratory issues.

As a result, EPA officials warn that beached sargassum should be removed as quickly as possible to avoid it clumping up and decomposing.