Since the beginning of man's association with the sea, the presence of bioluminescence has raised intense curiosity and awe.
Bioluminescence is the chemically based emission of visible light by living organisms.
Bioluminescent species can be found among most types of organisms, ranging from bacteria to fish. Below 1,000 meters, bioluminescence is the only source of light in the ocean. Sources in the upper water column are primarily members of plankton, with dinoflagellates, copepods, and euphausiids being the most common. Members of these three groups are of particular interest to the Navy as they can occur in sufficient numbers to create spectacular displays of light. Under certain environmental conditions, dinoflagellates may increase rapidly to concentrations which may discolor the water red, orange, yellow, green, or brown during the day.