Confirmed red tide in Miami-Dade, FL, closes some beaches
Scientists say they’ve discovered a species of algae in a Key Largo canal that causes a type of red tide linked to fish kills and sea mammals in other parts of the world.
But unlike the Karenia brevis red tide species that has infested beaches on Florida’s West Coast and turned up in Miami-Dade and three other East Coast counties, researchers with Florida International University said this week the Fibrocapsa japonica found behind the Pirate’s Cove subdivision is not associated with human illness.
“This particular algae is a natural part of the environment and often forms harmless blooms with no noticeable effects on marine life, but it has potential to cause fish kills if it persists for long time periods,” Tom Frankovich, the FIU scientist who discovered the algae on Oct. 2 said in a press release Tuesday.
The discovery “is not something to be alarmed about for now,” he said.
Fibrocapsa japonica is known to occur in organically enriched, enclosed environments, Frankovich said. In other words, most of the residential canals in the Keys are ideal breeding grounds.
The fish kills and mammal deaths associated with Fibrocapsa have been in Southeast Asia and the North Sea respectively, Frankovich said.
Frankovich’s findings were confirmed by Carmelo Tomas, a professor emeritus at the University of North Carolina Wilmington, who specializes in phytoplankton.
The Fibrocapsa was discovered almost by accident. Frankovich, who is based at FIU’s lab in Key Largo, was working on a report on red tide monitoring labs on the morning of Oct. 2, when he stepped outside for a break.
A man approached him and said he had red tide in his canal. Frankovich was skeptical but agreed to take a water sample and look at it in the lab.
He expected to find purple sulfur bacteria, which has been found in Key Largo canals in recent years, but when he looked through his microscope, it was clear he was witnessing specimens of a specific algae group. He narrowed it down to Fibrocapsa by the presence and location of unique cellular features scientists call mucocystes, which are located on the hind regions of the cells.
FIU notified Monroe County and other state officials, and sent additional samples to the Florida Fish and Wildlife Conservation Commission’s Harmful Algal Bloom laboratory.
Michelle Kerr, spokeswoman for the FWC, said water samples taken in the Keys in late September came back negative for Karenia brevis.
It was not immediately clear if FWC biologists have found Fibrocapsa while taking samples of other canals.