Understanding Red Tide
Understanding Red Tide
Red Tideblooms occurs when elevated concentrations of Karenia brevis are present in the water. View this infographic to learn more about red tide, including potential effects.
Infographic
FREQUENTLY ASKED QUESTIONS
FREQUENTLY ASKED QUESTIONS
- What is red tide?
A red tide event occurs when there is a high concentration of toxic dinoflagellates in the water.
Inthe Gulf of Mexico, the algae that causes most red tides is Karenia brevis, often abbreviated as K. brevis. At high enough concentrations, K. brevis can discolor water and give it ared or brown hue. Blooms caused by other algal species can also appear red or brown, but many also appear green or purple. Some algal blooms may actually appearcolorless.
Red tide events and other harmful algal blooms degrade water quality and harm Florida’s economy.
- How does red tide differ from blue-green algae?
Blue-green algae blooms occur primarily in freshwater water systems, whereas red tides tend to originate 10-40 miles offshore. Although wind and currents can pushred tides into nearshore waters, includingbays and estuaries, the algae that cause red tidescannot survive in freshwater systems.
- Where can I find out about red tide in my Area?
You can learn about red tide in your area by visiting the interactive statewide water quality map, or by visiting Florida Fish and Wildlife Conservation Commission.
Visit Statewide Water Quality MapVisit FWC
You can also subscribe to receive updates from Protecting Florida Together.
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- Is red tide dangerous?
Karenia brevis produces potent neurotoxins (brevetoxins) that can affect the health of both wildlife and people.For humans, aerosolized brevetoxins can cause respiratory irritation and/or illness if inhaled.
Finfish are safe to eat as long as they are caught alive and filleted.However, consumption of shellfish harvested from waters were red tide is present can lead to neurotoxic shellfish poisoning.It is not safe to eat clams, mussels or oysters from areas impacted by red tide.
- Where can I find status reports and additional information on red tide?
Florida Fish and Wildlife Conservation Commission provides red tide related status reports, hotlines and additional information.
- Where can I report health issues related to red tide?
To report health issues related to exposure to red tide, please call the Florida Poison Information Center at 800-222-1222.
- Where can I report fish kills, diseased fish or fish with other abnormalities?
The Fish and Wildlife Health Group at the Florida Fish and Wildlife Conservation Commission's Fish and Wildlife Research Institute in St. Petersburg has established a toll-free, statewide, fish kill hotline at 800-636-0511.
The hotline allows the public to report directly to researchers the locations of fish kills and diseased or abnormal fish. Callers should leave a brief message about the event they are reporting, mailing address, and telephone number so FWC staff can call back if they need additional information is needed.
Report Fish Kills and Fish Disease
Please call FWC Alert at 888-404-3922 if dead marine mammals or sea turtles are observed.
Additional Resources
Additional Resources
Water Quality Status Dashboard
Water Quality Status Dashboard
The Protecting Florida Together Water Quality Dashboard delivers relevant water quality information statewide including blue-green algae, red tideand nutrient monitoring data. This map helps to ensure transparency and accountability with respect to our water quality data and its exchange with the public.Information for this mapprovided by DEP and FWC.
Water Quality DashboardDashboard Overview
RED TIDE REPORTING
RED TIDE REPORTING
Red tide data displayed on the Water Quality Status Dashboardare identical to daily sample data on the Florida Fish and Wildlife Conservation Commission(FWC) site.
Both sites are updated daily. FWC provides additional information on red tide impacts such as fish kills and reports of respiratory irritation. Archived status maps and additional red tide resources are provided as well.
AQUATIC TOXINS PROGRAM
AQUATIC TOXINS PROGRAM
Staff at the Florida Department of Health’s Aquatic Toxins Program workevery day to keep Floridians and visitors to our state safe. DOH works in coordination with many partners, including DEP and FWC, to ensure public health is protected.
Shellfish Harvesting Status
Shellfish Harvesting Status
To prevent neurotoxic shellfish poisoning, harvesting of shellfish is prohibited in an area when cell concentrations of red tide organisms exceed 5,000 Karenia brevis cells per liter. The Florida Department of Agriculture and Consumer Services provides information on the current status of shellfish harvesting.
Photo Gallery
Photo Gallery
FWRI biologist reviewing potential deployment sites to set cameras and traps. NOAA invited FWRI biologists along with multiple partners on a South Florida Ecosystems research cruise aboard the R/V Walton Smith: Oct. 12-19, to sample the ongoing red tide on the southwest Florida Shelf. The focus will be on quantifying human health and ecosystem impacts from the red tide event.
FWC's Harmful Algal Bloom scientist counting Karenia brevis (red tide) cells during water sample processing.
Light micrograph image of K. brevis, the alga that causes most red tides in Florida.
Scanning electron micrograph image of K. brevis, the alga that causes most red tides in Florida.
FWC conducted an aerial survey for red tide in 2018. A patchy bloom was observed along the 1-mile survey line. Water discoloration was visible from Pinellas County to Sarasota County, within 3 miles from the coast.
FWC conducted and aerial survey for red tide in 2018. This photo was taken between the 5 and 10-mile survey lines. Although the bloom was patchy, defined golden-green streaks indicative of red tide were observed. Observations from the 10- mile survey estimated that the bloom extended at least 15 miles offshore in some areas. In particular, this was noted off of Manatee and Sarasota counties.
Image of red tide bloom taken from the shoreline. Photo courtesy of Florida Department of Health.
