The colossal squid, the heaviest invertebrate in the world, has been filmed alive in the wild for the first time since it was identified a century ago.
Growing up to 23ft (seven metres) long and weighing up to half a tonne, the squid, Mesonychoteuthis hamiltoni, is the heaviest invertebrate on the planet. The individual captured on film near the South Sandwich Islands, in the south Atlantic Ocean, is a baby, at just 11.8in (30cm) in length.
The video, taken by an international team of scientists and researchers on board the Schmidt Ocean Institute’s research vessel, Falkor, shows the almost transparent juvenile, with eight arms, swimming in its natural habitat, the deep sea. It was captured on video by a remotely operated vehicle, SuBastian, while on a 35-day expedition searching for new marine life.
“These unforgettable moments continue to remind us that the ocean is brimming with mysteries yet to be solved,” Virmani said.
For 100 years, the animal, a type of glass squid, had only been seen in the stomachs of whales and seabirds. Dying adults have previously been filmed in the nets of fishermen, but it had have never been seen alive at depth.
Little is known about the life cycle of the colossal squid, which loses its transparent appearance as an adult.
It took days for the team aboard the Falkor to get verification of the footage. The squid has sharp hooks on the end of its tentacles, which distinguish it from other glass squid species.
“It’s exciting to see the first in situ footage of a juvenile colossal and humbling to think that they have no idea that humans exist,” said Dr Kat Bolstad of the Auckland University of Technology, one of the independent scientific experts the team consulted to verify the footage.
The expedition was a collaboration between the Schmidt Ocean Institute, the Nippon Foundation-Nekton Ocean Census and GoSouth, a joint project between the University of Plymouth (UK), the Geomar Helmholtz Centre for Ocean Research (Germany) and the British Antarctic Survey.
This year marks the 100-year anniversary of the identification and formal naming of the colossal squid.
This article by Karen McVeigh was first published by The GUardian on 16 April 2025. Lead Image:
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