In a historic breakthrough, scientists have captured the first-ever footage of a live colossal squid in its natural deep-sea habitat, marking a significant milestone exactly 100 years after the species was first identified.

The remarkable video was recorded on March 9 by an international team aboard the Schmidt Ocean Institute’s Research Vessel Falkor (too) during an Ocean Census expedition in the remote South Sandwich Islands in the South Atlantic Ocean.

The juvenile colossal squid, measuring approximately 30 centimeters (nearly one foot) long, was filmed at a depth of 600 meters (1,968 feet) using the remotely operated vehicle (ROV) SuBastian.

The expedition, a collaboration between the Schmidt Ocean Institute, the Nippon Foundation-Nekton Ocean Census, and GoSouth, aimed to discover new marine life.

The footage revealed the squid’s transparent body, delicate arms, and distinctive hooks on its eight arms, a key characteristic of the colossal squid (Mesonychoteuthis hamiltoni).

Colossal squids, the world’s largest invertebrates, are estimated to grow up to 7 meters (23 feet) in length and weigh as much as 500 kilograms (1,100 pounds), equivalent to the weight of a small car.

Their elusive nature and deep-sea habitat near Antarctica have made them notoriously difficult to study.

Until now, most knowledge about the species came from remains found in the stomachs of whales and seabirds or from dying specimens caught by fishermen.

“For 100 years, we have mainly encountered them as prey remains or as predators of harvested toothfish,” said Dr. Kat Bolstad, a squid expert at Auckland University of Technology who verified the footage.

The discovery was a moment of excitement for the team.

Dr. Aaron Evans, an expert in the glass squid family (Cranchiidae), to which colossal squids belong, noted the significance of spotting the mid-arm hooks, which confirmed the squid’s identity. “I started hyperventilating,” Evans recalled during a press briefing, describing the thrill of the find.

The juvenile squid’s transparency, a trait typical of young colossal squids and other glass squids, highlighted its delicate beauty.

As these squids mature, they lose this see-through appearance, becoming more opaque as their muscles thicken.

The footage offers scientists a rare glimpse into the early life stages of this mysterious creature, about which little is known regarding its life cycle or behavior.

This milestone follows another achievement by the same team, who, in January, captured the first-ever footage of a glacial glass squid (Galiteuthis glacialis) in the Southern Ocean.

Unlike the colossal squid, the glacial glass squid lacks hooks on its arms, making the colossal squid’s features particularly distinctive.

The SuBastian ROV has proven instrumental in deep-sea exploration, having now recorded the first confirmed footage of at least four squid species in their natural habitats.

The expedition’s chief scientist, Dr. Michelle Taylor of the University of Essex, emphasized the power of telepresence technology, which allowed the taxonomic community to assist in real-time identification while the team was at sea.

The colossal squid’s elusiveness underscores how much remains unknown about the deep ocean.

The Natural History Museum has noted the challenge of estimating the global population of colossal squids, with their rarity causing them to “straddle the line between legend and reality.”

This unprecedented footage not only quells a century-long quest but also fuels curiosity about the ocean’s hidden giants, reminding scientists and the public alike that the deep sea is brimming with mysteries waiting to be explored.