Red tide monitoring updates from Mote in southwest Florida

Mote Marine Lab scientists are currently studying and monitoring the Florida red tide algae, Karenia brevis, off southwest Florida’s coast, while encouraging coastal communities to follow online updates, after noting increased signs of the harmful algae this week along southwest Florida.

On Oct. 9, the latest statewide red tide monitoring report from the Florida Fish and Wildlife Conservation Commission (FWC) ( said that blooms of K. brevis were present along and offshore of Bay and Gulf counties in northwest Florida, and along and offshore of Manatee, Sarasota and northern Charlotte counties in southwest Florida. In northwest Florida, counts of K. brevis cells ranging from the natural “background” to elevated “high” concentrations were detected in 12 samples collected in and alongshore of Bay, Gulf and Franklin counties, and background concentrations were detected in one sample collected offshore of Levy County. In southwest Florida, K. brevis was detected in background to low concentrations in 26 samples collected in, along and offshore of Manatee, Sarasota, Charlotte and Lee counties during the week leading up to Oct. 9.

Oct. 12 and 13 updates from Mote in Southwest Florida:

On Oct. 12 and 13, “medium” concentrations of K. brevis were detected in two samples collected by Mote scientists near the Lab’s main campus on City Island, Sarasota.

Today, Oct. 13, slight respiratory irritation and some dead fish were reported onshore at Venice North Jetty, and slight respiratory irritation was also reported at Siesta Key and Nokomis by Mote’s Beach Conditions Reporting System (BCRS:, which monitors conditions at multiple Gulf Coast beaches as often as twice daily. No impacts have been reported so far today at any other sites monitored by Mote’s BCRS.

People may experience respiratory irritation such as coughing, sneezing or a scratchy throat while at the shore or on the water when red tide algae cells are present in elevated concentrations. These symptoms are temporary and often considered an annoyance, but people with asthma, COPD or other chronic respiratory conditions should avoid areas with red tide algae, since the toxins can trigger their symptoms. Red tide concentrations elevated to low levels can be sufficient to cause respiratory irritation and may also kill fish. Many factors, including algae distribution, currents and winds, can determine whether effects are noticeable.
This week, Mote is monitoring for K. brevis by analyzing water samples collected by the Sarasota Healthy Beaches program of the Florida Department of Health from 16 locations along Sarasota County. These samples are collected weekly in a year-round monitoring effort.

Today and Wednesday, Oct. 13 and 14,  Mote scientists are collecting water samples from an area between approximately 10 and 50 miles offshore from near the mouth of Tampa Bay south to Captiva Island. At 14 sampling stations, Mote scientists will collect water at near-surface, mid-depth and near-bottom to analyze samples for multiple factors relevant to understanding Florida red tide blooms: nutrients, toxins, cells and the multi-species phytoplankton community. Satellite images from Oct. 13 suggest the red tide bloom, visible at the surface due to algal pigment chlorophyll, is present as a relatively small patch along Manatee and Sarasota counties. Sampling by boat will provide a more complete picture of what is happening offshore, where Florida red tides form, and beneath the surface, where satellites are unable to “see.”

Algae updates and resources
Red tide monitoring in Florida is accomplished through a unique collaboration between FWC’s Fish and Wildlife Research Institute, the Florida Department of Agriculture and Consumer Services (FDACS) and Department of Health, Mote Marine Laboratory, the University of South Florida, county agencies, other private non-profit agencies and citizen volunteers (i.e., the Red Tide Offshore Monitoring Program).

Updates and resources include:

FWC’s statewide red tide status reports (on abundance of K. brevis algae) are updated every Friday afternoon:
Based on statewide results, the National Oceanic and Atmospheric Administration provides forecasts of potential respiratory irritation:
Mote’s Beach Conditions Reporting System provides shoreline observations as often as twice daily:
Red tide background info from Mote and FWC, respectively (including FAQs): and
Red tide and human health – information and multi-lingual rack cards from Florida Department of Health:
FWC’s red tide offshore monitoring program – a way for volunteers to help.
FWC-Mote Facebook page, Florida Red Tide and Other Harmful Algal Blooms:
Trichodesmium (a benign algae that also occurs along the Gulf Coast) information from Mote: