Deep-sea squid emit flashes of light

Research has shown that large deep-sea squid emit blinding flashes of light as they attack their prey. Taningia danae's spectacular light show was revealed in video footage taken in deep waters off Chichijima Island in the North Pacific. Japanese scientists believe the creatures use the bright flashes to disorientate potential victims and say the squid are far from the sluggish, inactive beasts once thought. In fact, the footage reveals them to be aggressive predators. The squid, which can measure over 7ft in length, deftly swim backwards and forwards by flapping their large, muscular fins. They are able to alter their direction rapidly by bending their flexible bodies.

The blinding flashes of light were a surprise to scientists, as before now no one had ever seen such bioluminescence behavior while hunting for squid. The footage (see the article for links to video) reveals the creatures emitting short flashes from light-producing organs, called photophores, on their arms. Scientists note the light could serve several purposes, including disorienting prey, acting as a means to measure target distance, or even courtship.

The film captured the squid in action (picture below): 1. The squid swims towards the bait; 2. It spreads its arms wide; 3. It swims around the bait, twisting its body; 4. It grabs the bait with its eight arms.



Deep-sea squid are very difficult to study, and little is known about their ecology and biology. Several species prowl the ocean depths. Taningia danae is thought to be abundant in the tropical and subtropical oceans of the world. Larger species of giant squid belong to the Architeuthidae family: females are thought to measure up to 43ft in length. But the colossal squid (Mesonychoteuthis hamiltoni) is thought to be the largest of all - possibly reaching up to 46ft long.