Red tide observed at low levels in Sarasota County in FWC samples

Respiratory irritation linked to algae cited in recent reports for Siesta Key and Venice North Jetty beaches

This is a Karenia brevis cell. Image courtesy of Mote Marine Laboratory

In the aftermath of Tropical Storm Debby’s downpours in early August, which resulted in spills of millions of gallons of sewage into area waterways — and, ultimately, into Sarasota Bay — concern arose about whether the situation would result in a new red tide bloom.

For months, the Florida Fish and Wildlife Conservation Commission (FWC) weekly reports on red tide in Florida indicated no problems. However, on Sept. 6, the agency did note that the red tide algae, Karenia brevis, had been “observed at background concentrations in one sample from Manatee County.”

By the time of the Sept. 13 update, the algae had been seen in none of the samples collected over the preceding week.

Then, on Sept. 20, the FWC report said, “The red tide organism, Karenia brevis, was detected in 11 samples from Southwest Florida over the past week.” That report added, “We continue to use satellite imagery [provided through the University of South Florida and the National Centers for Coastal Ocean Science (NCCOS) of the National Oceanic and Atmospheric Administration (NOAA)] to help track nearshore and offshore conditions.”

“In Southwest Florida over the past week,” the report continued, K. brevis was observed at background to low concentrations in Sarasota County, background to very low concentrations in Pinellas County, background concentrations in Manatee County, and background concentrations in Charlotte County.

Moreover, the report said, respiratory Irritation potentially related to red tide was reported in Sarasota County from Sept. 17 through Sept. 19 at Siesta Key Beach; and on Sept. 18 at Venice North Jetty Beach.

These were among the conditions reported at Siesta Beach on Sept. 22, via Mote Marine’s Beach Conditions app. Image courtesy Mote Marine
These were part of the conditions reported at the Venice North Jetty beach on Sept. 23. Image courtesy Mote Marine

For recent and current information at individual beaches, FWC advises the public to check Mote Marine Laboratory’s Beach Conditions Reporting System. For forecasts that use FWC and partner data, the agency encourages the public to visit the National Oceanic and Atmospheric Administration’s Gulf of Mexico Harmful Algal Blooms Forecast.

This is a Sept. 25 map showing the respiratory forecast for part of the Sarasota County beaches. Image courtesy of the Gulf of Mexico Coastal Ocean Observing System

The next status report will be issued on Friday, Sept. 27, FWC added. “Please check our daily sampling map, which can be accessed via the online status report on our Red Tide Current Status page. For more information on algal blooms and water quality, please visit Protecting Florida Together,” the report said.

Prior to the reports on Sept. 6 and Sept. 20, the last FWC update to indicate the presence of the red tide algae in samples was released on June 14. For Southwest Florida, that report noted Karenia brevis’ having been observed in background concentrations in one sample from Sarasota County.

Moreover, the most recent FWC report about red tide in Southwest Florida before that June 14 update had been issued on March 22. In that situation, the algae had been “observed at background concentrations in two samples collected from and offshore of Sarasota County,” FWC said.