What Algae Causes Red Tide?

A red tide, or harmful algal bloom, is a higher-than-normal concentration of a microscopic alga (plant-like organism). In marine (saltwater) environments along Florida's west coast and elsewhere in the Gulf of Mexico, the species that causes red tides is Karenia brevis, often abbreviated as K. brevis.

Which algae usually cause red tide?

At least three species of dinoflagellates and one diatom species are responsible for the toxic mess of red tides in the United States. These microscopic forms of algae produce toxins that can sicken humans and be fatal for marine animals.

What algae causes red tide in Florida?

Like many harmful algal blooms in the Gulf, the Tampa Bay red tide is caused by a microscopic organism called Karenia brevis, which creates myriad concerns for coastal wildlife and people.