BiologyCoachOnlineBlog

The Firefly squid, Watasenia scintillans, is a species of squid in the family Enoploteuthidae. It is the only species in the genus Watasenia. It inhabits the Western Pacific ocean and may be found at depths of 600 - 1200 feet (183 - 366 meters). The creature's claim-to-fame is its bioluminescence (or natural ability to "glow" in the dark). Each of the animal's tentacles has a photophore - light-producing - organ which, when flashed, attracts small fish (the squid's prey). The Firefly squid measures about 3-inches (7.6 cm) long at maturity. It has a life span of only one year.

W. scintillans spends the day at depths of several hundred metres and returns to the water's surface at night fall. It uses its ability to produce light for counterillumination camouflage. That is, it matches the brightness and colour of its underside to the light coming from the surface thus making it difficult for predators to detect from below. The firefly squid can also light up its whole body to attract a mate. The phenomenon attracts spectators from around the globe as thousands of squid light up the shallows during the mating season (which lasts from March to June). The Firefly squid is commercially fished in Japan.