Florida researchers expecting red tide, but thats normal
NOAA has begun twice weekly reports for areas of the state, including Sarasota and Manatee counties, after higher than average levels were detected near Lee County.
SARASOTA — An oceanographer with the National Oceanic and Atmospheric Administration says a recent switch to twice-a-week red tide reporting was based on above-average concentrations of the toxic algae Karenia brevis found offshore from Lee County close to Captiva and Sanibel islands.
But this is not an actual red tide bloom, said Edward Davis, NOAA’s lead oceanographic forecaster, which includes scrutiny and prediction of harmful algal blooms.
>> READ MORE: Complete coverage of red tide in Southwest Florida
“The change that we’re seeing is pretty normal for the season,” Edwards said, noting that Florida red tide is normally detected from August to December and usually ends in February or March.
The reason for the double dose of reports that will be released Mondays and Thursday is “out of an abundance of caution,” the oceanographer said.
“It’s not a response to any sort of emergency,” Edwards said. “What we are seeing now is normal for this time of season, but higher than a naturally occurring amount. The very low concentrations are not bloom-level concentrations, but above the natural cell count.”
The forecasts that NOAA provides look ahead three to five days, and currently show “not present” to “very low” concentrations (0 to 10,000 Karenia brevis cells per liter). This pales when compared to levels well over one million, which were observed during the recent Florida red tide outbreak.
Thursday’s report said recent satellite imagery, partially obscured by clouds along the coast of Southwest Florida, signaled patches of elevated to very high chlorophyll from Sarasota to Collier counties. Two patches with the optical characteristics of Karenia brevis were also present alongshore Manatee and Lee counties.
The forecast called for favorable offshore winds through Monday, which would reduce the potential for respiratory irritation or bloom intensification at the coast.
Background concentrations of red tide also were noted in one sample from Bay County and one offshore from Pinellas County, while none was observed along the east coast of Florida. There have been no fish kills reported.
A normal year expected
Seventy-five percent of blooms begin in September and it “makes sense” to ramp-up monitoring, said Cynthia Heil, a senior scientist at the Harmful Algal Bloom Mitigation Research Program and director of the Red Tide Institute at Mote Marine Laboratory.
Heil said it would be more unusual not to have a Florida red tide bloom: “If it’s a normal red tide year, we will get a bloom anywhere from two- to five months-long.
The single-celled algae mysteriously occurs naturally 10 to 40 miles offshore, she said, and can be exacerbated by human-generated pollutants close to shore. Its origins and endings are the subjects of RTI’s current research.
“Last year was an atypical year,” Heil said. “It has people on edge for what will happen this year. We are reverting back to a normal year.”
The last bloomless year was 2010, said Heil, whose institute has been charged with finding methods, both in maintenance and termination, to curb future Karenia brevis outbreaks. The collaborative project encompasses six institutions, including multiple state partners, such as the Florida Fish and Wildlife Conservation Commission Research Institute, the University of South Florida and NOAA.
“Why was last year so bad? What makes some blooms so bad and some not bad in terms of impact, duration and intensity?” Heil asked. “What are the factors to ending the bloom, is it physical, biological, chemical or a combination? The state we know least about is termination. We are hoping to focus on these during investigatory cruises next month.”
The USF and FWC Collaboration for Prediction of Red Tides did not put out a summer red tide forecast because researchers did not have enough data to publish the report. That will not be a problem next year, says Heil. Robert Weisberg, distinguished professor of oceanography and marine modeler at USF, will have vast data in 2020, Heil said.
The RTI and USF are deploying buoys and underwater gliders to monitor the Gulf, while continuing to test natural mitigation applications, such as different types of seaweed that can kill Karenia brevis cells and compounds that can reduce aerosolized brevetoxins by 80%.
“We have some promising results from the different compounds,” Heil said.
New task force
On another front, Gov. Ron DeSantis’ Harmful Algal Task Force, commonly referred to as the Red Tide Task Force, met Thursday for the first time. The members focused on setting governance and guidance for the group. An overview of the meeting including public comments will be published on the FWC website.
DeSantis called for the organization of the task force on his second day in office through Executive Order 19-12, and made appointments to the team on Aug. 2.
Florida coastal residents are sensitive about elevated levels following the horrifying 2017-2019 bloom that wiped out generations of sea life and caused a “red tide hangover,” which has affected local tourism and led to a drop in hotel occupancy