Growth physiology of red-tide microorganisms.

The occurrence of red tides, which often cause mass mortality of marine animals and/or shellfish poisoning in humans, is increasing in the estuaries and coastal zones of the world. Species of dinoflagellates are most commonly responsible, though other flagellates, and even ciliates, can also cause red tides. In recent years, understanding of the growth physiology of red-tide microalgae has grown. Each causative organism has a species-specific preference and requirement for temperature, salinity, pH, the basic nutrients, and growth factors, and the toxin formation is affected by these environmental factors.