Red tide’s return

Last updated on August 8th, 2026 at 11:43 am

Red tide is beginning to show up in samples taken from Florida waters after months of lying low off-shore.

Still, there have been no confirmed fish kills or reports of respiratory irritation related to red tide in months,. Summer is considered peak season for red tide.

On Friday, August 7, 2026, the Florida Fish and Wildlife Commission reported the red tide organism, Karenia brevis, was observed at background to low concentrations in 13 samples from Florida’s East Coast, and background concentrations in seven samples along Florida’s Gulf Coast. 

  • In Southwest Florida over the past week, K. brevis was observed at background concentrations offshore of Hillsborough County, and in Manatee, Charlotte and Collier counties. For specifics, view the Southwest Coast report and map.
  • In Northwest Florida over the past week, K. brevis was observed at background concentrations in Wakulla County. For specifics, view the Northwest Coast report and map.
  • Along the Florida East Coast over the past week, K. brevis observed at background to low concentrations in Nassau County and background to very low concentrations in Duval County. For specifics, view the East Coast report and map.
red tide statewidewidemap0807 Red tide's return

Fish Kills

No fish kills suspected to be related to red tide have been reported to FWC’s Fish Kill Hotline or other partners over the past week.

Respiratory Irritation

Respiratory irritation believed related to red tide was not reported over the past week.


Red tide FAQ

red tide redtide sampling Red tide's return
Red tide sampling. (FWC photo)

What is Red Tide? Common name for harmful algal blooms occurring along coastal regions in Florida from large concentrations of aquatic micro-organisms, specifically an organism called karenia brevis. Bloom events are stimulated by nutrients from terrestrial runoff containing fertilizer, sewage and livestock wastes.

Should I avoid red tide? Toxins from red tide can cause breathing problems and irritate your eyes, nose and throat. Reactions to red tide are worse for people with asthma, emphysema, bronchitis or any chronic lung disease. If you have health issues, stay away from areas with red tide. Pets can become sick from red tide, so keep them away from those areas, as well as contaminated marine animals and fish.

Red tide can cause illness and death in pets.

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Red tide at its peak off southwest Florida coast in previous years.

Can we swim near red tide? Don’t swim in or around red tide because the toxin can cause skin irritation, rashes and burning and sore eyes.

What should I do if I come in contact with Red Tide? Wash off with soap and water. You can get relief from respiratory symptoms by being in an air-conditioned space. For people without asthma or chronic respiratory problems, over-the-counter antihistamines can help. If your symptoms don’t get better, see a doctor.

What about the dead fish on the beach? Red tides kill fish and other marine life — avoid contact and don’t swim or walk in areas with dead fish. Keep your pets away from these areas. Don’t harvest or eat distressed or dead fish (or any animals) from or near a red tide. Fish caught live and healthy can be eaten if filleted and rinsed thoroughly with fresh water.

Are shellfish affected by Red Tide? Crabs, lobsters, shrimp, clams, oysters and scallops are filter feeders that can concentrate toxins. These and other shellfish, if harvested from red tide areas, may be contaminated.

Does freezing weather kill the red tide organism?

Freezing weather does not directly kill the organisms (Karenia brevis) responsible for Florida red tide, but it can help dissipate blooms by disrupting their growth and pushing them offshore with strong winds.

While cold snaps may reduce the severity, they do not destroy the toxins, which remain active even in cold water. 

For more details, go to the FWC’s Red Tide page.


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