Red Tide Status Update: 11/13/24

Over the past week,  red tide was detected in 55 samples collected from Southwest Florida. Bloom concentrations (>100,000 cells/liter) were observed in five samples: one from Manatee County and four from Sarasota County. 

Satellite imagery (USF, NOAA) continues to show a long offshore patch (>100 miles long) of elevated chlorophyll, spanning Pinellas to Collier counties, and a few isolated patches further north, off of Pasco County and the Big Bend region. We are participating in an ongoing, multi-day survey that is conducting offshore and coastal sampling along Southwest Florida.

Underway analysis using an Imaging FlowCytobot (IFCB, McLane Instruments) has confirmed the patchy presence of Karenia brevis from and/or offshore of Pinellas to Collier counties (not shown). Additional samples will be examined via light microscopy once the survey is completed.

Additional details are provided below.

• In Southwest Florida over the past week, K. brevis was observed at background to low concentrations in Pinellas County, low concentrations in Hillsborough County, background to medium concentrations in Manatee and Sarasota counties, very low concentrations in Charlotte and Lee counties, and very low concentrations offshore of Collier County.
• In Northwest Florida over the past week, K. brevis was not observed.
• Along the Florida East Coast over the past week, K. brevis was not observed.

Fish kills suspected to be related to red tide were reported to FWC’s Fish Kill Hotline and other partners over the past week for Southwest Florida (Pinellas and Charlotte counties).

Respiratory irritation suspected to be related to red tide was reported over the past week in Southwest Florida (Sarasota County). For forecasts that use FWC and partner data, please visit the National Oceanic and Atmospheric Administration’s Gulf of Mexico Harmful Algal Blooms Forecast.

Forecasts by the USF-FWC Collaboration for Prediction of Red Tides for Pinellas County to northern Monroe County predict net northwestern movement of surface waters and net southeastern transport of subsurface waters in most areas over the next 3.5 days. We are keeping a close watch on the disturbance in the Caribbean and associated forecasts, which will likely impact ocean currents and short-term red tide predictions.  

The next status report will be issued on Friday, November 15^th. 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.

This information, including maps and reports with additional details, is also available on the FWRI Red Tide website. The website also provides links to additional information related to the topic of Florida red tide including satellite imagery, experimental red tide forecasts, shellfish harvesting areas, the FWC Fish Kill Hotline, the Florida Poison Information Center (to report human health effects related to exposure to red tide), and other wildlife related hotlines.

To learn more about various organisms that have been known to cause algal blooms in Florida waters, see the FWRI Red Tide Flickr page. Archived status maps can also be found on Flickr.       

The FWRI HAB group in conjunction with Mote Marine Laboratory now have a facebook page.  Please like our page and learn interesting facts concerning red tide and other harmful algal blooms in Florida.