Red Tide Status Update: 11/26/24

Over the past week, red tide was detected in 73 samples collected along Florida’s Gulf Coast, from Northwest and Southwest Florida. Bloom concentrations (>100,000 cells/liter) were observed in 14 samples: one from Hillsborough County, four from Manatee County, and nine from Sarasota County. We are continuing to use satellite chlorophyll imagery (USF, NOAA NCCOS) to track this bloom.

Several distinct, offshore patches of elevated chlorophyll were visible in satellite data from November 25: 25 to 30 miles off of parts of Dixie, Levy, and Citrus counties, 30 to 35 miles off of parts of Hernando and Pasco counties, 12 to 22 miles off of Manatee and northern Sarasota counties, and 10 to 20 miles off of northern Lee County. Recent observations from earlier this month suggest that these patches likely contain red tide, but conditions continue to be dynamic over space and time and until we have samples, we cannot confirm. Offshore samples from some areas are expected to arrive prior to the Thanksgiving holiday.

Several field campaigns were conducted between yesterday and today. Sample processing is ongoing and rather than share a static map, we encourage you to please visit our GIS-based daily sample map at https://myfwc.com/redtidemap/ for the most up-to-date information on where red tide has been observed over the past 8 days. This map is updated four times a day and will capture samples processed beyond this mid-week status update. Individual sample details can be obtained by zooming into an area of interest and clicking on each sample dot.   

 Additional details are provided below.

• In Southwest Floridaover the past week,  K. brevis was observed at background to low concentrations in Pinellas County, medium concentrations in Hillsborough County, very low to medium concentrations in Manatee County, background to high concentrations in Sarasota County, and low concentrations in Charlotte County.
• In Northwest Florida over the past week, K. brevis was observed at background concentrations in one sample collected from Franklin County.
• 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 along Sarasota County. Additional fish kills were reported offshore of Levy and Citrus counties, but we have not yet received samples from this area.

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 predict variable movement of surface waters and net southeastern transport of subsurface waters over the next 3.5 days, from Pinellas County to northern Monroe County. For the Big Bend area, forecasts predict variable movement of surface waters and minimal subsurface transport over the same time frame. This suggests that surface populations of K. brevis will continue to be spatially dynamic over the next few days, and that onshore transport of subsurface populations is possible, particularly for Southwest Florida.

Due to Thanksgiving holiday, the next status report will be issued on Wednesday, December 4^th. Please check our daily sampling map, which can be accessed via the online status report on our Red Tide Current Status page.

This information 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.