A colossal squid is caught on camera for the first time in the deep sea

A colossal squid, or Mesonychoteuthis hamiltoni, during an Ocean Census flagship expedition in the South Sandwich Islands in the South Atlantic Ocean, Sunday, March 9, 2025. (ROV SuBastian/Schmidt Ocean Institute via AP)

A colossal squid has been caught on camera for the first time in the deep sea by an international team of researchers steering a remotely operated submersible.

The sighting was announced Tuesday by the Schmidt Ocean Institute.

The squid filmed was a juvenile about 1 foot (30 centimetres) in length at a depth of 1,968 feet (600 metres) in the South Atlantic Ocean. Full-grown adult colossal squids, which scientists have uncovered from the bellies of whales and seabirds, can reach lengths up to 23 feet (7 metres) — almost the size of a small fire truck.

The squid was spied last month near the South Sandwich Islands during an expedition to search for new sea life. Researchers waited to verify the species identification with other independent scientists before releasing the footage.

“I really love that we have seen a young colossal squid first. This animal is so beautiful,” said Kat Bolstad, a squid researcher at the Auckland University of Technology in New Zealand, who helped confirm it.

Researchers are testing different cameras in hopes of catching an adult colossal squid, Bolstad said.

The young squid is almost entirely transparent, with thin arms. As adults, the squids lose this glassy appearance and become an opaque dark red or purple. When full grown, they are considered to be the world’s largest known invertebrates.

AP video journalist Mustakim Hasnath contributed to this report.

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Christina Larson, The Associated Press