Bioluminescence acts as a burglar alarm. The fish is more liable to find and eat the larger copepod than the miniscule dinoflagellate cell. In this way the predators of the dinoflagellate are removed. When the copepod sees the luminescent flash it gives a jump, because staying put means it is vulnerable to predation. The result is that the feeding behavior of the copepod is disrupted and less dinoflagellate prey are consumed.
Light is produced as a result of a chemical reaction.
Therfore, light production in dinoflagellates and all other luminescent organisms involves a chemiluminescent reaction in which a substrate, luciferin, is oxidized, releasing a large amount of energy in the form of light. Unlike light produced by light bulbs, in which a portion of the energy is wasted as heat, most of the energy released from the chemiluminescent oxidation of luciferin occurs in the form of light. All bioluminescent reactions occur in the presence of oxygen. At neutral pH, LBP stabilizes the luciferin from being spontaneously oxidized. When activated by a drop in pH, the luciferin dissociates from LBP, and associates with a protein, luciferase, which acts as a catalyst.