A team of researchers from four universities has revealed that a microbe normally found in waterways emits a poison not just to protect itself, but to stun and immobilize the prey it plans to eat, which could help curb massive fish kills.

The researchers studied the performance of the algal cell Karlodinium veneficum, known as a dinoflagellate and found in estuaries worldwide.

Studies show Karlodinium veneficum emits a poison called karlotoxin that immobilizes its victim a single-celled algae called cryptophyte, the researchers wrote this week in the events of the National Academy of Sciences.

Karlodinium veneficum blooms spread the toxin, which harm the gills of fish. The frequency of the algae blooms could be abridged by limiting the nutrient load that feed's Karlodinium veneficum's prey and by bringing back the Eastern oyster, which once was the bay's most prolific microbe filter, said Allen Place of Maryland's Institute of Marine and Environmental Technology.

Karlodinium veneficum is a predicament in estuaries worldwide and millions of dollars are spent annually trying to control it.