By Janet Raloff
Marine scientists have been documenting a disquieting trend in the past few decades–increasing blooms of poisonous algae. Outbreaks in Chinese coastal waters, for example, increased 10-fold between 1975 and 1995. Many species tint the water a deep hue, from red or blue-green to dirty brown. Others proliferate
more stealthily. Recognition of their intoxicating presence generally dawns only when wildlife or people sicken.