Red tide occurs when algae rapidly increase in numbers to the extent that it dominates the local planktonic or benthic community. Blooms are caused by environmental conditions that promote explosive growth. Such high abundance can result from explosive growth caused by a metabolic response to a particular stimulus or from the physical concentration of a species in a certain area due to local patterns in water circulation, warm sea surface temperatures and high nutrient content.

Galvez, J.K. (2016, March 08). Red tide alerts still up in Visayas coastal areas. The Manila Times, p. A7.