Red Tide Algae

Background
Algae are vitally important to marine ecosystems, and most species of algae are not harmful. However, under certain environmental conditions, microscopic marine algae called Karenia brevis (K. brevis) grow quickly, creating blooms that can make the ocean appear red or brown. People often call these blooms “red tide.”


Red tides occur throughout the world, affecting marine ecosystems in Scandinavia, Japan, the Caribbean, and the South Pacific. Scientists first documented a red tide along Florida’s Gulf Coast in fall 1947, when residents of Venice, Florida, reported thousands of dead fish and a “stinging gas” in the air, according to Mote Marine Laboratory. However, Florida residents have reported similar events since the mid-1800s.