As the tenacious and patchy red tide lingers off Sarasota and Manatee counties, experts are closely monitoring changes in ocean currents for signs of a new bloom that could make matters worse.
The amount of red tide measured in local waters has changed this week, conditions intensifying to average levels along most of Anna Maria Island and dropping slightly to low to average levels in Sarasota County. Medium levels are sufficient to be considered a bloom. The only place with high levels of red tide measured on Thursday was near New Pass in Sarasota Bay.
With fall fast approaching, University of South Florida physical oceanography professor Bob Weisberg said the coming months could be a big turning point for the local red tide.
Weisberg creates models to track and predict ocean currents, much like meteorologists follow the wind.
“It looks very promising”: Mote expands red tide research
And: New pond program aims to improve water quality in Sarasota Bay and reduce red tide
Scientists first measured red tide in Sarasota County in April and Manatee County in May, and the bloom has plagued the region ever since. During the summer, hundreds of tons of dead fish washed up in Sarasota, Manatee and Tampa Bay.
The red tide became less concentrated in mid-September, and although levels have steadily increased since then, flowering has become more uneven.
Beach conditions have been mixed in recent weeks with many visitors enjoying crystal clear water, while others were greeted by more visible areas of murky red tide.
Lessons learned during the 2018 red tide give Weisberg reason to remain wary.
That year, a lingering bloom from the previous year never fully faded, then gulf conditions pushed a new red tide ashore to add more strength. Killed fish have had a significant economic impact in Sarasota and Manatee after devastating tourism.
“I wouldn’t be surprised if it happened again this year,” Weisberg said. “Typically, red tide forms in the middle of the continental shelf in late spring during the summer months. Then, as the fall sets in, that water – with its red tide that was offshore – is carried up to the beach and concentrate.
Experts have been tracking the ongoing red tide since last winter, when it bloomed in Gulf waters near Charlotte Harbor. Cells of Karenia Brevis, the organism that causes the red tide, slowly moved north, causing blooms in areas where conditions were ripe, Weisberg said.
“This year he behaves a little differently,” Weisberg said. “Now that it’s autumn and the conditions were probably right for red tide organisms to grow offshore, and the winds are finally starting to reverse, these new red tide cells could be coming.”
In case you missed it: Manatee County Lobbying for Water Taxi, OKs Mote Center and Other Projects on Anna Maria Island
The red tide continued to migrate north along the Florida Gulf Coast, carrying cells to the Florida Panhandle, where Panama City is facing an intense bloom.
“I think the concentrations are going to fluctuate over the next month or so, and eventually we’ll see if we get another red tide bloom or just get this patchy back and forth,” Weisberg said.