Elusive colossal squid filmed swimming in deep ocean for first time

The world's heaviest squid has been caught on video in its natural deep ocean habitat for the first time. Well, a tiny "teenage" specimen of the colossal squid ( ) that measured 30 centimetres-long. But one day the delicate cephalopod could weigh as much as half a tonne and grow more than 7 metres long.

Despite being first described 100 years ago, we know very little about the life cycle and behaviour of colossal squid, which are only found in waters surrounding Antarctica. Adult and juvenile specimens have been collected before but the mysterious creature has not been observed before at depth. The new footage was captured in March by the Schmidt Ocean Institute, a not-for-profit research group, during a voyage near South Georgia and the South Sandwich Islands.



The colossal squid juvenile was filmed near South Georgia and the South Sandwich Islands, while the largest most intact adult specimen was collected at the Ross Sea in 2007. The juvenile was spotted about 600 metres below the ocean surface by a high-definition camera on a remote operated vehicle, called "Subastian". Deep-sea biologist Kat Bolstad, from Auckland University of Technology, was not on the trip but helped identify the species in the footage.

"We get to introduce the live colossal squid to the world as this beautiful little delicate animal that highlights the magnificence of a lot of deep-sea creatures without some of that 'monster' hype." The remotely operate vehicle "Subastian" can dive as deep as 4,500 metres. Aaron Evans, who studies glass squids, was also asked by the Schmidt Ocean Institute to confirm the footage was of a colossal squid.

Dr Evans said it appeared to be a juvenile of the species that had grown out of its "baby" phase. "It no longer has stalked eyes. The eyes are part of the head itself," he said.

"We could think of this maybe as a 'teenager' squid ...

it's still got a lot of growing to do." The recently filmed juvenile squid was about 30 centimetres in size while the mantle of the 2007 specimen kept in Te Papa, New Zealand, measures about 2.5 metres in length.

Marine biologist and giant squid expert Steve O'Shea, who was not part of the expedition, said to his knowledge it was the first time a colossal squid, adult or juvenile, had been filmed in its natural habitat. "It is lovely to see this species being filmed by scientists in a non-invasive way, alive rather than dead on a trawler deck or mangled in a net," he said. Giant vs colossal squid, what's the difference? Colossal squid are considered the largest cephalopods by mass, weighing up to half a tonne.

Conservative estimates suggest colossal squid get up to about 7m, including its two massive trailing tentacles, but lengths of more than 10m have been hypothesised. The arms of the colossal squid have gripping hooks. They have the largest eyeballs of any living creature at 27.

5 centimetres in diameter, which is a little bigger than a basketball. The giant squid ( ) is weighs less than a colossal squid but is longer, with the longest on record being 13m long. Giant squid are found in all of the world's oceans but it wasn't until 2012 when high-definition colour video was taken of adults in waters off Japan.

It was also filmed in the Gulf of Mexico in 2019. But similar vision of adult colossal squid has eluded scientists. What we knew until now about colossal squid has mostly come from a handful of specimens.

The most intact is a female squid caught in the Ross Sea in 2007, now displayed at the Museum of New Zealand Te Papa Tongarewa in Wellington. She was brought up from about 1,500m deep, hanging onto a toothfish caught by commercial fishers. She weighed about 470 kilograms.

A colossal squid specimen caught in 2007 in the Ross Sea in Antarctica. Another ocean exploration not-for-profit organisation called Kolossal previously filmed a glass squid in 2023 they thought could be a juvenile colossal squid but the footage was too grainy and the species' identity has not been verified. Dr Bolstad said the opportunity to see a live juvenile colossal squid provided some insights into the species.

"It's got ...

large rust-red, brown chromatophores [cells that produce colour]," she said. "The spots on the mantle [the tube-like body] tells us that it almost certainly can switch back and forth between being completely transparent ..

. to being quite opaque." Scientists think the juvenile colossal squid can switch between being transparent and opaque.

But Dr O'Shea said there was not too much we could learn from the video since scientists had already collected several juvenile specimens in the past. He said there were still so many unanswered questions when it came to the colossal squid. "How does its behaviour change throughout its life cycle? What does the male look like? How long does the species live and how fast does it grow? "An expedition into these waters is needed, and its sole objective must be to learn about this animal.

" Will an adult colossal squid ever be filmed in the deep? The Schmidt Ocean Institute won't be heading back towards Antarctica until 2028, so if an adult is filmed in the deep in the next few years, it will be by another group. Schmidt Ocean Institute research vessel named "Falkor (too)" was used to track down the juvenile colossal squid caught on camera. There is ongoing research as to whether environmental DNA testing could help narrow down locations for trying to film adult squid.

Dr Evans said unlike the giant squid, there weren't as many opportunities to bump into a colossal species due to the remoteness of its home. The urge to avoid noisy equipment may also hinder the search. "The colossal squid in particular has ginormous eyes," Dr Evans said.

"It's able to see the remotely operated vehicle long before the remotely operated vehicle sees it. "So most adult colossal squid are probably going to try and want to get out of the area as much as possible because, from their perspective, anytime something large is coming towards them, it's not a good thing." The beak of a colossal squid collected in 2003.

The colossal squid is prey for sleeper sharks and sperm whales, with squid beaks often found in the predators' stomach. Dr Bolstad said different strategies were needed to try not to scare the squid and instead attract it to cameras, "which is an idea that several different research teams have been developing". Although it will be a challenge, marine scientist and Kolossal founder Matt Mulrennan believes colossal-sized adult squids are out there waiting in Antarctica to be filmed.

Science in your inbox.