How much smelly seaweed will Florida see this year?

The smelly seaweed mountains wash land at Miami Beach and Key Biscayne.

Brown seaweed is a common sight across the Caribbean and South Florida beaches.

Researchers tracking seaweed blooms hope that 2025 will be another “major Salgassum year” in the Atlantic Basin, but the amount of seaweed cleaning on land on beaches in South Florida depends on wind and flow.

The Sargassum season is from March to October.

“The University of South Florida University of Marine Science has created a new research associate professor of research at the Institute of Optical Oceanography, part of the University of South Florida University of Marine Science,” said Brian Burns, assistant professor of research at the Institute of Optical Oceanography, a part of the University of South Florida University of Marine Science.

In the ocean, seaweed provides important habitat for marine life. However, when seaweed washes land, the smell of rotten eggs can put dampers on the beach day.

Cleaned seaweed can also cause health problems in people with chronic respiratory illnesses.

Here’s other things you need to know:

Why does seaweed smell so bad?

Brown seaweed washing on Florida beaches is known as Sargassum. When the seaweed is washed, hydrogen sulfide gas, which smells like rotten eggs, rot and starts to release.

What is Florida Seaweed Prediction?

It is common to see seaweed on the beach, but the Sargassum season can bring a large amount of land.

It predicts whether seaweed will flood the beaches in Florida and Caribbean, and when it will be complicated. That could change soon.

For several years, Burns led a federally funded project to create predictive models that help predict when and where large patches of seaweed will be washed.

He expects a test version of the model to be released later this year, with initial predictions set to focus on the Florida Keys and other South Florida. Similar models from Puerto Rico and US Virgins Island could be released in 2026.

The forecasting model is part of a five-year $3.2 million grant awarded in 2023 by the Federal National Oceanic and Atmospheric Administration. Barnes’ USF team is working on the model with researchers from Boca Raton at Florida Atlantic University, the Caribbean Coastal Ocean Observing System, NOAA’s Atlantic Marine Botany and Metrology Institute, and the US Virgin Islands Planning Agency.

But what does the current data tell you?

“There are many salgassums offshore, from the keys and even in the Gulf of Mexico,” Burns said. Seaweed said wind and currents often gather in these areas before shifting Bloom to Florida Keys, Key Biscayne and Miami Beach. Future forecasting models want to predict whether seaweed will remain offshore or will eventually float on the beach.

In Miami Beach, for example, “stronger than usual eastern and southeastern winds are likely to contribute to increased cleaning in Salgassum,” city spokesperson Melissa Bartier said in an email statement to the Miami Herald. “The general winds bring seaweed floating mats closer to the coastline, bringing the heavy deposits we’ve seen along our beaches recently.”

Are there any seaweed hotspots in Miami?

Florida may see seaweed flowers this season, but that doesn’t mean that all the beaches will be full of it until October. Sargassum appears on the chunks of beaches as the tide is high and the wind blows from east to west, pushing seaweed towards the shore.

According to the Salgassum webpage in Miami-Dade County, the biggest accumulation of Salgassum in Miami-Dade Beach occurs twice a day, twice a day between tides. County crews generally remove stinking seaweed early in the morning before most beach fans arrive. “Unfortunately, when the second tide arrives in the afternoon in response to the wind, another wave of Sargassum often comes to the coastline,” the county said.

A large-scale seaweed washing landed in Key Biscayne on April 24th. Some of the Miami Beach coastline have recently seen a more seaweed buildup compared to other regions.

On April 28, webcams on the Greater Miami and Miami Beach websites showed dark pockets of water and coastline seaweed in the beach areas of 17th and 18th Avenue early in the morning. Meanwhile, the beach area on 10th Avenue had less seaweed on the water and coastline, Berthier said.

It’s hard to predict which beaches will get a seaweed blanket, but Miami-Dade County has identified four seaweed hotspots. Bal Harbor just south of Haulover Cut. Miami Beach between 26th and 31st Avenues. A beach along South Point Pier.

The Sargassum season also coincides with the Miami-Dade sea turtle nesting season. This means that sea turtle nests must be marked before seaweed cleanup begins in Miami Beach, and is considered an important nest habitat for loggerheads, green and leatherback sea turtles.

Health problems from hydrogen sulfide

Hydrogen sulfide gas seaweed is released when rotten and stimulates the eyes, nose and throat. Small sea creatures living in seaweeds like jellyfish and lice can also cause skin rashes and blisters.

“If you have asthma or other respiratory illnesses, you may be sensitive to hydrogen sulfide. Monroe County’s Florida Department of Health may have difficulty breathing after inhaling.”

People who have been exposed to hydrogen sulfide for a long period of time in an enclosed space, like workers at wastewater treatment plants, can become ill with dizziness, headaches, stomach upset and apnea, according to the Federal Centers for Disease Control and Prevention.

“However, hydrogen sulfide levels in areas like beaches, where large amounts of airflow can be diluted, are not harmful to health,” according to the Monroe Health Department. There are also no signs that gas will cause cancer in humans. Anyone experiencing severe problems should call 911.

Miami-Dade County is also turning to evolving information about the relationship between salgassum and warm coastal bacteria, which can cause rare and severe, life-threatening infections, including the infection known as “carnivorous bacteria.”

Recent research on researchers at the University of Florida Atlantic suggests that this warm coastal aquatic bacteria, Vibrio vulnificus, can “stick” to microplastics, commonly found in our oceans and can get stuck in Sargassum. According to NBC News, scientists have found that open ocean vibrio bacteria have similar genetic properties to Vibrio species that can cause human disease. People usually get infected with bacteria by eating raw shellfish, especially oysters, or through open wounds that come into direct contact with salt water.

“I don’t think anyone should run away from Sargassum like they’re going to kill them,” Linda Amaral-Zettler, a marine microbiologist at the Royal Dutch SEA Institute and one of the authors of a recent study, told NBC News. “It’s simply not. But I think we need to be responsible for the potential risk.”

What if there is a lot of seaweed on the nearby beach?

Health officials generally recommend that people living near the beach leave their windows and doors closed. Florida Keys health officials recommend that anyone with asthma or other respiratory problems be away on the beach or shortened their time if they have seaweed. If you don’t want to risk stinging by animals living in seaweed, don’t touch it.

And think again before you think about bringing seaweed home and cooking.

The Florida Department of Health said that it’s not a good idea as Sargassum could contain “a large amount of heavy metals like arsenic and cadmium.”