An elusive squid species uses its large photophores to stun and disorient its prey while attacking. (Image credit: UWA/Inkfish)
One of the world's hardest-to-find squid species put on a spectacular bioluminescent display as it attacked an underwater camera in the deep sea, rare new footage shows.
Researchers from the Minderoo Foundation and the University of Western Australia's (UWA) Centre for Deep Sea Research captured the unique encounter, which occurred approximately 3,281 feet (1,000 metres) below the surface of the Pacific Ocean, using a baited free-fall camera dropped into the sea near the Samoan Channel – an area of deep-sea current north of Samoa.
The team was on a research cruise documenting the diversity of the deepest part of the ocean – the hadal zone – when they spotted this rare creature.
The animal in the video is an octopus squid (Taningia danae), a member of the Octopoteuthidae family, which feeds on pelagic fish, crustaceans, and other squid species.
Squids from the Octopoteuthidae family have eight limbs, which is why they are called octopus squids. When young, they have two long, elongated tentacles that disappear as they mature.
Members of this species are known for their enormous size. According to a 2003 study, the longest specimen ever reported was a female measuring 7.5 feet (2.3 m). The UWA claims the specimen in the new video is about 2.5 feet (75 centimeters) long.
In the footage, the squid suddenly emerges from the darkness and lunges towards the camera, wrapping its tentacles around it before sprinting away. Moments before it latches onto the camera, the squid displays a pair of bright light-emitting organs known as photophores at the tips of two of its tentacles.
The species' photophores, which emit flashes of light through a chemical reaction, are the largest of their kind in the animal kingdom, the researchers said in a statement. However, scientists have rarely observed squid's biological lights in action.
“When we looked through the footage, we realised we had captured something very unique,” Heather Stewart, a marine geologist and research fellow at UWA, said in a statement. “I think we were really lucky to have witnessed this.”
Researchers believe squid photophores help them stun their prey in the dark waters of the deep sea and possibly communicate with other members of their species. These squid can change their flash patterns by controlling the eyelid-like membranes that cover their light-producing organs, according to a 2017 study.
Sourse: www.livescience.com
