Summer 2018’s Red Tide event in the Gulf of Mexico has brought to bear the severe impacts of harmful algal blooms on both coastal habitats and communities.

What is Red Tide?

Red Tide is a term used to describe what scientists refer to as harmful algal blooms (HAB’s). When high algal concentrations are present, the water can appear to have a murky reddish colour. Occuring in oceans, bays, and brackish waters, these blooms are influenced by a number of factors such as wind, temperature, nutrients, and salinity.

HAB events can be deadly to marine habitats and ecosystems. The current event affecting the Gulf of Mexico, and now FLorida’s Atlantic coast as well, contains the brevetoxin Karenia brevis. While K.brevis is always present in the Gulf, the high concentrations found during bloom events can result in mortality for a number of marine species, and pose a health risk to humans as well.

The Red Tide event of 2018 is unique for its timing, duration, and size. This event started earlier than normal, has lasted longer, and is affecting a much larger area. Originally present in six county’s along the Gulf side of Florida, in early October 2018 K.brevis has also been found along Florida’s Atlantic coast between Palm Beach and Miami.

How does this affect my beach day?

As with any measurement of recreational water quality, HAB’s vary day to day in their location and concentration. If concentrations are high enough, breaking waves can cause toxins to mix with sea spray, posing a threat to beach goers. While Swim Guide reports fecal indicator bacteria test results for Florida Beaches, it is always best to check with the local health authority, NOAA’s Harmful Algal Bloom Bulletin, or the Florida Fish and Wildlife Conservation Commission Red Tide Status page before heading to the beach.

What Can I do?

There are many ways you can contribute to protecting Florida’s coast. Reporting any Red Tide impacts you see to local health authorities, staying informed about current conditions (see section below), and volunteering your time to local groups like Tampa Bay Waterkeeper and Miami Waterkeeper are all great options. You can also contributing directly by submitting photos though Swim Guide’s new Photo Submission Tool. These photos go into our Beach Image database and serve as valuable pieces of environmental evidence. It’s a simple way to become a citizen scientist and help protect your local waters.

Stay Informed about Red Tide

Below we’ve compiled a list of useful resources to help you stay informed and up-to-date on Red Tide events. Florida Fish and Wildlife have a realtime Google Earth map displaying all current red tide advisories.

NOAA Fact Sheet on Red Tide event in the Gulf of Mexico
NOAA Harmful Algal Blooms Links and Resources
Science Daily Red Tide Face Sheet
Florida Fish and Wildlife Conservation Commission Red Tide Current Status
Florida Healthy Beaches Red Tide Blooms Information
Lee County, FL
Sarasota County, FL
Collier County, FL
Pinellas County, Fl

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