Florida officials confirmed a rare red tide on the state’s Atlantic coast on Monday after beach goers began complaining about coughing and itchy throats along Palm Beach County over the weekend.
While not as high as amounts detected on the Gulf Coast, where a ferocious red tide that appeared last fall has littered beaches with dead sea life, clogged canals with floating carcasses and slammed businesses, the medium levels were bad enough to trigger respiratory distress among beach visitors.
“They picked up concentrations that are high enough,” said National Oceanic and Atmospheric Administration algae expert Richard Stumpf. “There’s obviously more data to be collected.”
In a press release, Florida officials said they could not yet confirm the exact amounts. A spokeswoman said the state was collecting samples where visitors complained of symptoms.
“Red tides on the East coast of Florida are extremely rare. They can even subside and then reoccur,” the statement said. “The duration of a bloom in near shore Florida waters depends on physical and biological conditions that influence its growth and persistence, including sunlight, nutrients and salinity, as well as the speed and direction of wind and water currents.”
The appearance of a red tide on the east coast comes as the state’s water problems continue to mount. Over the summer, a freshwater blue-green bloom coated most of Lake Okeechobee and exploded in rivers when the U.S. Army Corps of Engineers was forced to release water to protect the 730-square mile lake’s aging dike. Those conditions have also become fodder in a heated election year, with Gov. Rick Scott challenging longtime Sen. Bill Nelson.
As late as Friday, regular testing showed no elevated levels along the east coast, according to the state’s web site.
No fish kills have been reported on the east coast, although Palm Beach and Martin county officials closed several beaches while they investigated.
Stumpf, who tracks harmful algae blooms using NOAA satellite imagery, said hints of the tide were detected near the Marquesas Islands east of the Dry Tortugas in August and September. But around the Tortugas, where waters are much clearer, the algae can live in waters as deep as 65 feet, making it difficult for satellites to see, he said.
It’s likely that the Gulf of Mexico’s Loop Current picked up the algae and swept it south and then up the east coast.
Once it moved up the coast, an eddy off the Gulf Stream or winds could have blown it ashore, said University of Miami algae expert Larry Brand. It also would have likely missed much of Miami-Dade where the Gulf Stream flows further from the coast.
“So it could have gotten there and incubated over the last few months,” he said.
The last time a red tide occurred on the east coast was in 2007, Stumpf said. It appears rarely on the state’s east coast because the saltwater algae that cause it, Karenia brevis, live at the bottom of the Florida Shelf off the state’s west coast, causing regular blooms along the Gulf Coast between the spring and fall.
This year’s tide, however, has raged for nearly a year and worsened over the summer after May’s record-breaking rain. The rain could have caused more coastal pollution, which feeds the algae, to wash into the Gulf. Polluted lake water, filled with freshwater blue-green algae blooms could have provided even more food for the red tide when it hit the coast and died and exacerbated the blooms, scientists say.
Since 1953, 57 red tides have been documented in the Gulf, Florida Fish and Wildlife Conservation officials said in a statement. Of those, eight have made it to the east coast, all occurring along Palm Beach County, Florida officials said.