Red Tide

Name:
Red Tide
Detailed information:
Yellow-to-reddish discoloration of seawater due to rapid multiplication of various species of plantlike microorganisms, called dinoflagellates, which occurs seasonally in areas of warm water, especially off the coast of Florida and occasionally as far north as New England. Some, though by no means all, of the species are poisonous. Concentration of these organisms (phytoplankton) may be as high as 10⁸ units/L. The shelfish are lethal to free-swimming fish. Shellfish are unharmed by them, but are able to store and concentrate the toxin which causes paralytic poisoning when they are eaten by humans. So potent is this poison that death may result from ingestion of milligram amounts.