The Colossal Squid Was Never Hiding. We Just Couldn't See It.

[00:00:06]Most squid have suckers on their arms, small, circular, lined with teeth, standard predatory equipment. The colossal squid has hooks, not fixed hooks. rotating hooks, each one mounted on a swivel joint capable of spinning as a full 360°, designed to lock into flesh and not release regardless of how violently the prey moves. They line all eight arms and both longer tentacles on the club-shaped ends of those tentacles. Each hook is individually articulated. It can angle itself in any direction mid-grip.

[00:00:45]This animal is the heaviest invertebrate on Earth. Its mantle alone, just the main body, not the arms, can reach 2 to 4 m long. Total weight up to 700 kg.

[00:00:59]That's heavier than a grizzly bear, a Bengal tiger, and a saltwater crocodile combined. Its eyes are 27 cm in diameter, the size of a basketball, the largest eyes of any animal that has ever existed in the 4 billionyear history of life on this planet. It has three hearts. Its blood is blue. For 100 years, we knew all of this from dead specimens and from what came out of whale stomachs. We had never seen one alive. not at depth, not in its actual environment, not doing what it actually does until March 9th, 2025.

[00:01:39]And what that footage showed us made scientists question almost everything they thought they understood about this animal.

[00:01:49]Before we get into the footage, there's a misconception that's been running for decades, and it's important to clear it up. Most people when they think of a giant deep sea squid picture the giant squid archetus ducks. The one in old sailor paintings with tentacles wrapped around ships. The one Jules Vern wrote about. The one with the 2004 footage that made international news. The colossal squid is a completely different animal. The giant squid is longer. It can reach about 13 m including its feeding tentacles. But it's built like a whip. Narrow, light, fast. The colossal squid is shorter at around 10 m, but it is built like a vault. Wider mantle, denser muscle, enormously heavier.

[00:02:39]Estimates of maximum weight for a giant squid around 275 kg.

[00:02:45]Maximum weight for a colossal squid up to 700 kg.

[00:02:51]Same category, more than twice the mass.

[00:02:54]The colossal squid also has those hooks, which the giant squid does not. And it lives in the southern ocean around Antarctica in some of the most remote and inaccessible water on the planet.

[00:03:08]Here's the problem with building a century of scientific understanding on a single animal. We found the colossal squid by accident. Not through targeted searching, not through deep sea exploration, through a sperm whale's digestive system. In 1924, a sperm whale was caught in the southern ocean. When researchers opened the stomach, they found something unusual. Not just the typical squid beaks and mantle fragments, but tentacle pieces with hooks unlike anything documented before.

[00:03:41]Scientists examined the hooks, the tissue, the anatomy. They named the species Messikotuis Hamiltoni in 1925.

[00:03:51]We named an animal we had never seen alive, identified it from digested remains, built our entire initial understanding of it from what a whale was breaking down for nutrients. And for the next 100 years, that's essentially how it stayed. Because getting eyes on a live colossal squid in its actual environment turned out to be close to impossible. And as we'll get to, the colossal squid had something to do with that. Let's go through what the dead specimens and whale stomach archaeology actually told us. Because even on paper, this animal is absurd.

[00:04:29]Start with the hooks. The arms, all eight of them, have hooks running their full length. These aren't optional.

[00:04:37]They're not for special circumstances.

[00:04:40]Every contact surface on every arm is armed. The two longer feeding tentacles end in club-shaped structures where the hooks are individually swiveing. The mechanical function is straightforward.

[00:04:52]When this animal grabs something, the hooks drive inward and rotate, embedding into whatever they've contacted. The prey item is now attached. It does not come off by pulling away. Pulling away makes the hooks rotate deeper. The beak is worth its own section. Squid beaks are the only hard structures in their bodies. Everything else is soft tissue.

[00:05:16]The colossal squid's beak is the largest of any squid species, large enough to cleanly sever the head of a large fish in a single action. The beak is also significantly harder and denser than the surrounding tissue.

[00:05:32]This creates a problem for anything that eats a colossal squid hole. The beak doesn't digest. It sits in the predator's stomach, still sharp, still structurally intact. Sperm whales have been found with internal scarring consistent with colossal squid beak damage. The squid can continue injuring whatever ate it from the inside after it's dead. The eyes at 27 cm in diameter. Some estimates push to 30 cm.

[00:06:03]These are the largest eyes of any known creature in the history of life on this planet. Not just the largest among squid, not just the largest among invertebrates, the largest of any animal. Full stop. Eyes cost metabolic resources. Big eyes cost enormous metabolic resources. Evolution does not produce structures this large, this expensive, unless there's a very specific and very serious reason for them. In 2012, researchers published a study in the journal Current Biology with a specific conclusion.

[00:06:43]The eyes of the colossal and giant squid are uniquely sized for one function. Not finding prey, not navigating, detecting the bioluminescent wake of an approaching sperm whale.

[00:06:58]When a sperm whale dives into deep water, and begins using its echolocation, a sonic system loud enough to physically stun prey, the sound pulses disturb bioluminescent organisms in the water around it. This creates a faint moving glow in the direction the whale is coming from. a light signature visible against the darkness. The colossal squid's eyes are specifically optimized to detect that signature at the distance. Those eyes can detect it.

[00:07:29]The squid has enough time to react, to move, to avoid. The largest eyes in natural history did not evolve to see better. They evolved to see one specific predator coming in time to survive the encounter. We'll come back to that predator because the relationship between the colossal squid and the sperm whale is the most important and most violent ecological relationship in the southern ocean and it's one-sided in a way that changes how you understand both animals. The Schmidt Ocean Institute's research vessel Falor was in the South Atlantic Ocean running a 35-day expedition near the South Sandwich Islands, one of the most remote island chains on the planet, roughly halfway between the southern tip of South America and Antarctica. The mission was an ocean census expedition searching for new species in the southern ocean. ROV Subastion, a remotely operated vehicle, was deployed on regular dives. On March 9th, at 600 meters depth, Sebastian's cameras picked up a squid. The scientists aboard didn't immediately know what they were looking at. The expedition didn't have a dedicated squid expert on board. What they saw on the monitor was, in the words of expedition scientist Natasha Taylor, a beautiful glassy squid. Small, transparent, almost entirely see-through, organs barely visible through its tissue, drifting with an unhurried quality.

[00:09:04]The footage was transmitted to experts on shore via the ship's teleresence system. Dr. Dr. Cat Bolstad at the Auckland University of Technology reviewed it. Dr. Aaron Evans, another independent expert on the glass squid family, reviewed it separately. Evans later said he began hyperventilating when he noticed something on the footage. The hooks, those rotating, swiveling hooks on the club ends of the tentacles, the feature that distinguishes the colossal squid from every other member of its family. right there on camera at 600 meters depth on an animal nobody on the ship had realized they were filming. Both experts confirmed it independently. This was a juvenile colossal squid. The first confirmed live footage of the species in its natural habitat in the hundred years since it was identified. Bolstad's response when the identification was confirmed.

[00:10:01]It's exciting to see the first insitu footage of a juvenile colossal and humbling to think that they have no idea that humans exist. And then more pointedly, for 100 years, we have mainly encountered them as prey remains in whale and seabird stomachs and as predators of harvested toothfish. 100 years.

[00:10:24]Prey, remains, and stomach contents.

[00:10:27]That's the complete record of direct human knowledge of the largest invertebrate on Earth prior to March 9th, 2025.

[00:10:36]But what the footage actually showed was not what anyone had pictured. And that discrepancy matters more than almost anything else in this story.

[00:10:47]The colossal squid in the footage was 30 cm long, about the size of a ruler. It was completely transparent. Not translucent, transparent. You could see through the mantle, see the faint internal structures, see the light from Sebastian's flood lights passing through the tissue. It moved slowly, deliberately, with a kind of unhurried precision that looked nothing like the violent, aggressive, tentacle everywhere creature that a 100red years of dead specimens had suggested. It looked, in the words of Dr. Bolstad like a beautiful little delicate animal. This is the part that scientists are still working through.

[00:11:33]Everything we believed about the behavior of the colossal squid was built on animals that had been hauled to the surface in fishing nets, dragged from the stomachs of caught whales, found washed up on beaches in various states of decomposition. dead specimens, damaged specimens, specimens that had been through extreme physical trauma before we ever observed them. We were building behavioral models for a live animal based on what it looked like after it was already dead. The live footage shows a slowm moving ambush predator, not a fast, aggressive hunter.

[00:12:09]This matches what the biology already suggested. The energy requirements of a 700 kg body in near freezing water favor stillness over constant motion. But the assumption had always been that something this armed, this large, this heavily equipped with rotating hooks must be aggressive. The footage shows it isn't. Or at least it doesn't have to be.

[00:12:36]There's one more thing the footage revealed that doesn't get mentioned enough. The juvenile was at 600 m.

[00:12:44]That's relatively shallow for this species. Adult colossal squids, the ones found in whale stomachs, are being eaten at depths exceeding 2,000 m. The juvenile we filmed was nowhere near adult territory. That means what we filmed was essentially the baby zone, the shallow end, the part of the colossal squid's life we might with effort be able to access. The adults have never been filmed alive, not once.

[00:13:14]And there's a reason for that, which comes back to those basketball-sized eyes and what the colossal squid uses them for.

[00:13:22]Here are the numbers that define the relationship between the colossal squid and the sperm whale.

[00:13:30]14% of the squid beaks found in Antarctic sperm whale stomachs are colossal squid beaks. That percentage sounds modest until you account for size. A colossal squid is so much heavier than other squid species that 14% of the beaks represents approximately 77% of the total biomass those whales are consuming. In the southern ocean, the sperm whale runs almost entirely on colossal squid, not as a supplementary food source, as the primary energy supply. The food chain of the world's largest tooththed predator is built almost entirely on one animal. This one.

[00:14:13]Look at the flanks of sperm whales caught or observed in Antarctic waters.

[00:14:18]You will find scars, long curved marks too wide for teeth, too precise for random damage. The shape and spacing match colossal squid hooks exactly. made when a squid in the process of being swallowed drove its rotating hooks into the whale's skin and held on.

[00:14:39]The beak damage mentioned earlier, internal injuries, hooks in the flesh.

[00:14:44]The colossal squid does not go quietly, but it does go. Sperm whales consume it by the tens of thousands of tons annually across the southern ocean. The squid is not winning this relationship.

[00:14:57]It is the prey. And this is why those eyes are the way they are. The sperm whale uses its bio sonar. Those 236 decel clicks that rattle water molecules at close range. While diving, the sound pulses excite bioluminescent organisms in the surrounding water. A faint glow appears in the direction the whale is approaching from. The colossal squid's 27 cm eyes, specifically calibrated for low light detection at depth, can see that glow from a distance that gives it time to move. Not much time, but enough.

[00:15:34]20 million years of sperm whales eating colossal squid selected generation by generation for larger and larger eyes until those eyes reach the physical limit of what soft tissue can produce.

[00:15:48]The world record for eyes exists because a squid needed to see a whale coming a little earlier than the previous generation could. Which brings us back to the question of why nobody has ever filmed an adult colossal squid alive.

[00:16:05]Dr. Bolstad made an observation about the colossal squid and underwater cameras that I think deserves more attention than it's received. She said, "They know we are there long before we know they are there. They are actively avoiding us." Think about what that means operationally. An ROV descends into the deep ocean. It has lights. It produces sound from its thrusters. It disturbs the water as it moves. In the dark, at depth, a colossal squid at some distance has a large pair of eyes specifically evolved to detect faint visual disturbances in low light conditions. calibrated over millions of years for exactly this kind of detection task. The ROV cannot see the squid until it's within the range of its flood lights, maybe 10 to 20 m in good conditions. The squid can likely detect the ROV's light disturbance and acoustic signature from much, much further away.

[00:17:05]By the time the camera is anywhere near where a colossal squid was resting, the squid is already somewhere else. This is not speculation. It is the most likely explanation for why, despite decades of deep sea ROV operations in the Southern Ocean, we had never captured confirmed footage of a live colossal squid at depth. Not because they are rare, not because our equipment isn't good enough, because the animal is specifically built to notice us and leave before we arrive.

[00:17:39]The juvenile on March 9th may have stayed in frame precisely because it was a juvenile, not yet fully developed, not yet running the full avoidance behavior of an adult.

[00:17:51]Adults live below 2,000 m in waters we can reach with current ROV technology, but only barely. They can see our cameras before our cameras see them. We don't know how many of them exist. We don't know exactly how they reproduce at depth. We don't know what sounds, if any, they produce. We don't know how they interact with each other.

[00:18:14]Everything in that list, the entire behavioral biology of the adult colossal squid is currently unknown. The heaviest invertebrate on this planet, living in the most remote ocean on Earth, specifically adapted to avoid detection, and 77% of the diet of the largest tooththed predator in existence.

[00:18:35]We know essentially nothing about its life.

[00:18:40]What we have is 30 cm, a juvenile, transparent, moving slowly through 600 m of cold southern ocean water, completely unaware that a remotely operated vehicle was filming it. Completely unaware that the footage was being transmitted to scientists on another continent who were confirming its identity while literally hyperventilating.

[00:19:05]Completely unaware that humans exist.

[00:19:08]Dr. Bolstad called it a starting place, a first data point for understanding the life cycle of an animal that science has been trying to understand for a 100red years from stomach contents and trwler nets. It is a starting place. That's the accurate description. The adult colossal squid at 10 m and potentially 700 kg is somewhere below 2,000 m in the southern ocean right now. It has rotating bone hooks on every arm. A beak that can cause internal injuries after death.

[00:19:43]Eyes the size of basketballs calibrated to one specific task. Three hearts and blue blood and tissue saturated with enough ammonia that almost nothing will voluntarily eat it raw. It is watching in the sense that those eyes are processing the deep water around it, looking for the bioluminescent signature of a 50tonon predator bearing down from above. It has been doing this for tens of millions of years.

[00:20:12]In a 100 years of trying, the best we've managed is a 1-oot juvenile on a 35day expedition, briefly on camera before moving off frame. The adults know we're there long before we find them. We've been looking for a hundred years.

[00:20:28]They've been watching us the whole time.