Florida Red Tide

"Florida red tide is a natural phenomenon which occurs in the waters surrounding the state of Florida."
It is but one of the many interesting facts about Florida! The locals already know about it. As a visitor to the area, you need to know about it too. No one likes surprises.


First of all, I’d like to shoot down a few myths regarding these events.

It does not just occur in the waters around Florida. It is a global phenomena.

These natural events are nothing new. There are ancient Egyptian records describing such events.

Interesting Facts about this Natural Phenomenon!

  • A natural phenomenon which causes the water in certain areas to be red, rusty brown or greenish in color
  • The water color change is caused by the high concentration of pigment from the phytoplankton
  • Sometimes the water doesn’t change color at all during a bloom
  • Scientists have suggested that the name of this phenomena be changed as the blooms aren’t always red and the events have nothing to do with the tides!

  • Caused by warm water surface temperatures, often in the warm weather, stagnant water conditions, and an over abundance of nutrients in the water
  • Under these ideal conditions, the phytoplankton undergo rapid growth
  • The phytoplankton in this rapid growth phase emit toxins
  • There are many theories regarding the cause. Some believe that land pollution, fish farms, sewage and farm fertilizer run-off, drain to the body of water, and in turn, these excess nutrients feed the algae, causing it to overproduce

Where Does Red Tide Occur?

These events are a global phenomena occurring around mostly in the waters around California, Mexico, Florida, Hawaii and the Northeast U.S.

The events usually localized. Often just a particular area is affected, not an entire coast line.

Red Tide Effects

The bloom harms wildlife, marine ecosystems, coastal aesthetics and the tourist economy.

It can destroy fish, make clams and oysters unsafe to eat as they are filter feeders and it releases harmful airborne substances.

These airborne substances can also eye irritation and respiratory issues, if the phytoplankton washes in on the beaches.

It is advised that anyone with respiratory issues should stay away from the beaches until the tide clears up.

Don’t eat clams and oysters during a bloom. They are filter feeders and take in the toxic substances.

Shellfish are safe to eat, such as crab, lobster and shrimp. They are not affected by the bloom, as they aren’t filter feeders.


  • Apparently, it’s ok to swim during a bloom, but it could cause some minor skin irritation. Do stay out of the water though if you already have any sort of respiratory issues.
  • Also don’t forget to keep your pets away from the water.

Red tide is a natural occurence in the waters surrounding Florida and it is hoped that with funding, further research will enable early predictions of these mysterious natural events and also the ability to mitigate the blooms when they occur, especially near populated and environmentally sensitive areas.

Check for Gulf of Mexico beaches.

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