Red tide effects pop up on Longboat Key beaches

The side effects of red tide were prominent on Longboat Key beaches on Feb. 17.

Piles of dead fish accumulated near the tide line, creating a stench prominent from the beach access parking lots. These effects began over the weekend, according to some resident reports. 

Red tide blooms are caused by an abundance of the bacteria Karenia brevis. When red tide blooms occur, the algae can cause respiratory issues and cause widespread fish kills. The fish kills then wash ashore and exacerbate respiratory issues. 

The smell of red tide is different from the smell of dead fish, but both can cause respiratory issues. 

According to resident Sheila Loccisano, the red tide conditions were worse over the weekend. 

“It was definitely in the air,” Loccisano said. 

On Saturday, she said the irritation was slight to moderate, including a slight throat-burning irritation. Then, on Sunday, everything was worse when she woke up to take a sunrise stroll on the beach. 

“I was shocked when I got up in the morning on Sunday,” Loccisano said. “The beach was covered in fish.”

Loccisano runs the Instagram account @followmetolongboatkey through which she documented the beach conditions throughout the weekend. 

By Monday, Loccisano said the water quality seemed to be better, but the fish kill was still prominent in some beach areas.

The last samples recorded by the Florida Department of Health in Sarasota County on Feb. 10 reported no karenia brevis cells in the water off of Longboat Key, but a large cell count further south near Blind Pass and Manasota Beach. 

A red tide alert was issued for several southern Sarasota County beaches in November 2024, and local agencies have been monitoring the presence of red tide since that alert. 

Earlier this month, Mote Marine Laboratory & Aquarium unveiled new technologies and strategies to combat red tide blooms that could be used in situations of large red tide blooms. 

Mote Marine also has a beach conditions monitoring program that relies on community reporting of dead fish and overall beach status. This map can be found at VisitBeaches.org/map.