Red Tide Bulletin (September 28, 2018)

A bloom of the Florida red tide organism, Karenia brevis, persists in Southwest Florida and extends along ~130 miles of coastline, from northern Pinellas to southern Lee counties, and extends offshore (10 miles or more). A patchy bloom of K. brevis also continues in Northwest Florida. Additional details are provided below.

Over the past week in Southwest Florida, K. brevis concentrations generally decreased in areas of Pinellas, Manatee, Sarasota, Charlotte and Collier counties, creating patchier bloom conditions along the coast. Observations of >1,000,000 K. brevis cells per liter (“high” concentrations) occurred in Manatee, Sarasota, and Lee counties and >10 miles offshore of Hillsborough County, but at fewer sites relative to last week. In Northwest Florida, K. brevis was observed in or offshore of Walton, Bay, Gulf, and Pasco counties, with up to “medium” concentrations observed in Bay and Gulf counties. Relative to last week, cell counts increased in areas of Bay County and decreased in Okaloosa County.

In Southwest Florida over the past week, K. brevis was observed at background to medium concentrations in or offshore of Pinellas County, low to high concentrations offshore of Hillsborough County, background to high concentrations in Manatee County, background to high concentrations in or offshore of Sarasota County, background to medium concentrations in Charlotte County, background to high concentrations in or offshore of Lee County, and low concentrations in Collier County. In Northwest Florida over the past week, K. brevis was observed at very low concentrations offshore of Walton County, low to medium concentrations in Bay County, background to medium concentrations in Gulf County, and background to very low concentrations in or offshore of Pasco County.

We continue to receive reports of fish kills related to Florida red tide. In Southwest Florida, reports of fish kills were received for multiple locations in and/or offshore of Pinellas, Manatee, Sarasota, Charlotte, Lee and Collier counties. In Northwest Florida, reports of fish kills were received for Walton, Bay and Gulf counties. More detailed information is available at http://myfwc.com/fishkill. Respiratory irritation was reported in Southwest Florida (in Pinellas, Manatee, Sarasota, Lee, and Collier counties). Respiratory irritation was not reported in Northwest Florida over the past week.

Forecasts by the USF-FWC Collaboration for Prediction of Red Tides for Pinellas to northern Monroe counties predict net northwestern movement of surface waters and southeastern transport of subsurface waters for most areas over the next three days. Three-day forecasts for Northwest Florida predict net southeastern transport of surface waters and northeastern movement of subsurface waters from Escambia to western Gulf counties. Forecasts for Pasco County predict net northwestern transport at the surface and eastern movement of subsurface waters over the next 3 days.

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.

Additional information regarding the current status of algal blooms in South Florida is being consolidated and posted on the Florida Department of Environmental Protection’s website: https://floridadep.gov/dear/algal-bloom.