Fish kills can start when levels reach 10,000 cells per liter. In 20 Florida locations, concentrations were higher than 100,000. Health alerts for red tide have been issued in Lee, Collier counties.

Add Yahoo as a preferred source to see more of our stories on Google. Whether you're a native Floridian or a seasoned visitor to the state's coasts, you know it only takes a visit from one unwanted ...

See more of our trusted coverage when you search. Prefer Newsweek on Google to see more of our trusted coverage when you search. Floridians on the Gulf Coast are facing a "high risk" of irritation ...

SARASOTA, Fla. — If you're traveling to the Tampa Bay area this Thanksgiving, you may want to check the latest red tide conditions before you hit the beach. The harmful algal bloom is still very ...

Red tide has waters off Southwest Florida in the "kill zone." Caused by the Karenia brevis organism, red tide is no stranger to Florida waters. They've been documented in the Gulf of Mexico — soon to ...

Red tide blooms have been reported along Florida's Gulf Coast. Swimming in areas with red tide can cause skin irritation and burning eyes, especially for those with sensitive skin. People with severe ...