Ocean explorers have finally achieved one of their most alluring but elusive goals: video footage of the legendary giant squid (Architeuthis dux)in its natural deep-sea habitat. Scientists say that the spectacular film, captured during an expedition off Japan’s Ogasawara archipelago, answers enduring questions about the enigmatic invertebrate.
The 6-week mission was funded by the Japan Broadcasting Commission (NHK) and the US Discovery Channel, and took place in July. It is only now being discussed publicly, as the two companies prepare to broadcast documentaries that include the footage later this month.
The squid was first glimpsed using a specialised camera system, called Medusa, which the team deployed from a ship and left suspended about 700 metres down in the water. Later, researchers came face-to-face with one while in a submersible. “It was so beautiful that I have no words to explain it,” says zoologist Tsunemi Kubodera of Japan’s National Museum of Nature and Science, who was in the submersible. … The camera system was developed by Edith Widder, a deep-sea explorer and founder of the Ocean Research and Conservation Association in Fort Pierce, Florida. She thinks that the key to its success was a focus on the squid’s sense of sight. To avoid bright lights that might scare the squid away, the system uses a low-light camera with a dim red light, because few deep-sea animals see light with such a long wavelength.
In hopes of drawing the animals in, Widder used a different sort of light. Although very little sunlight penetrates to the deep sea, many deep dwellers produce a bioluminescent light. Past research by Widder suggests that the bioluminescence can act as a sort of burglar alarm, among other functions1. The idea is that the bioluminescence produced by some prey when they are attacked may serve to attract larger predators — such a giant squid — that will then eat the attacker.
… Medusa ended up encountering a squid five times, culminating with a full view of one apparently attacking the camera system in a manner consistent with the alarm hypothesis. The squid was about 4 metres long, although giant squid can grow as large as 10 metres or more. …
Read more: Nature
A 23 minute close encounter with a giant squid!