A colossal squid was filmed alive in the deep ocean for the first time ever

For the first time on record, a colossal squid has been filmed alive in its natural habitat in the deep ocean. The animal, a small juvenile drifting in the dark waters of the South Atlantic, was captured on video by a remotely operated submersible roughly a century after the species was first identified and named.

The colossal squid is one of the ocean’s most storied creatures, long known mainly from carcasses, from beaks recovered inside the stomachs of predators, and from dying specimens hauled up by fishing vessels. Seeing a healthy one alive at depth, going about its life, closed a gap that had persisted since scientists first described the animal.

A see-through juvenile near the South Sandwich Islands

The footage was recorded during a deep-sea expedition near the remote South Sandwich Islands, a frigid, isolated arc in the South Atlantic, using the remotely operated vehicle SuBastian operated from a research vessel. The squid was filmed at a depth of around six hundred meters and measured about thirty centimeters, close to a foot long, according to the research team that captured it.

At that age the animal was almost entirely transparent, a glassy, delicate form suspended in the water column. Colossal squid lose that see-through quality as they mature, so the juvenile offered a look at a life stage rarely observed. The sighting was live-streamed as part of an effort to let scientists and the public follow deep-sea expeditions in real time, meaning the historic moment unfolded in front of a remote audience rather than in a sealed lab.

The heaviest invertebrate on Earth

Fully grown, the colossal squid, known to science as Mesonychoteuthis hamiltoni, is thought to reach around seven meters in length and to weigh as much as five hundred kilograms, which makes it the heaviest invertebrate known to exist, as accounts of the animal describe. That bulk sets it apart from the giant squid, a different species that can grow longer but is far more slender and lighter.

The species also carries a distinctive piece of anatomy: rotating hooks on its arms and tentacles, used to grip prey in the deep. It has some of the largest eyes in the animal kingdom as well, an adaptation suited to detecting the faint light and movement of predators and prey in an environment where sunlight never reaches.

Why it stayed unseen for a hundred years

The colossal squid was first named in the twentieth century, but the living animal proved extraordinarily difficult to observe. It inhabits the cold, deep waters around Antarctica, a region that is both physically punishing and expensive to reach, and it appears to spend its life at depths where human access has historically been minimal.

What scientists had instead were fragments and the occasional dying adult. Beaks turned up in the stomachs of sperm whales and large fish that feed on the squid, and a handful of whole specimens were recovered near the surface in poor condition. None of that revealed how the animal actually moves, hunts, or behaves when healthy and undisturbed in its own habitat, which is exactly what a live sighting at depth begins to show.

What remotely operated vehicles changed

The breakthrough owes much to the technology now available for exploring the deep sea. Remotely operated vehicles like the one used here can descend far beyond the reach of human divers, hover quietly, and record high-resolution video without the disturbance a crewed submarine might cause. That combination of endurance, mobility, and a light touch is what allowed a small, fragile squid to be filmed without being frightened off or destroyed.

Such vehicles have steadily rewritten what is known about deep-ocean life, turning creatures once glimpsed only as damaged remains into animals that can be watched alive. The colossal squid footage is a marquee example of that shift, but it fits a broader pattern in which the deep sea, long treated as effectively unreachable, is becoming a place scientists can observe directly.

A milestone rather than a full answer

A single juvenile does not settle the many open questions about the colossal squid. Researchers still have limited direct knowledge of how the animals grow, how they hunt at full size, how long they live, and how their populations are faring in a rapidly changing Southern Ocean. The value of the footage lies in proving that observing them alive is possible and in providing a first, concrete reference point for behavior and appearance in the wild.

It also underscores how much of the ocean remains unexplored. That an animal this large and this famous could go unseen alive for roughly a hundred years after being named is a reminder that the deep sea still holds basic surprises, and that the tools now being deployed to explore it are likely to keep turning up firsts. For a species that has loomed in the imagination as a near-mythical giant, the quiet image of a small, transparent juvenile drifting in the dark is a rare piece of solid evidence.

This article was researched and drafted with the assistance of AI and reviewed before publication.

More from Morning Overview