Giant Squid: The Real-Life “Kraken” of the Deep

Arthur here, your monocled deep-sea tour guide. Today we’re dropping far below the sunlit waves to visit a creature so strange it inspired legends of sea monsters: the giant squid.

For centuries, sailors told stories of tentacled beasts pulling ships under the waves. The truth, as usual, is even more interesting. The giant squid is real, rare, and still a mystery in many ways. Scientists mostly meet them as washed-up giants on beaches or tangled in deep-sea fishing nets, because they spend their lives far below where sunlight can reach.

How big is “giant”?

The giant squid is the longest known squid on Earth. Well-preserved specimens reach around 12–13 metres from tip to tip—that’s longer than a school bus, with much of that length in stretchy feeding tentacles. Most weigh a couple hundred kilograms, but at least one record-breaker tipped the scales at over 300 kg.

In 2022, one of these deep-sea giants washed ashore on Scarborough Beach in South Africa. Even missing some of its length, it still measured over four metres long, giving scientists a rare chance to collect samples and learn more about how these animals live.

Arms, tentacles, and that famous beak

Like all squid, giants have a soft torpedo-shaped body called a mantle, with fins at the back for steering, and a head ringed by limbs. They carry eight arms covered in suckers plus two extra-long tentacles for grabbing prey. The suckers can be a few centimetres across and are lined with tough, serrated rings that bite in like tiny circular saws.

Those toothy suckers leave perfect circle scars on the faces of sperm whales, which tells us two things: whales eat giant squid, and the squid do not go quietly. Once a giant squid has hold of dinner, it reels the prey in and passes it to a sharp beak and a shredder-like tongue called a radula to tear food into bite-sized pieces.

Where does a giant squid hide?

Giant squid live in the deep ocean, usually hundreds of metres down, in cold, dark water between about 300 and 1,000 metres deep—and possibly deeper still. They seem to roam many of the world’s oceans but usually steer clear of the warmest tropical waters and the coldest polar seas.

Down there, daylight is gone. Any light comes from bioluminescent animals—tiny flashes from plankton, fish and jelly-like creatures. It’s a quiet, shadowy world where a giant squid’s best tools are stealth and some of the largest eyes in the animal kingdom.

Dinner-plate eyes and a brain built for the dark

A giant squid’s eye can be the size of a dinner plate, up to about 27 cm across. Those massive eyes are great at catching the faintest traces of light. One idea is that they help the squid spot the glowing trail of bioluminescence stirred up by a hunting sperm whale, giving the squid time to dodge away before becoming dinner.

Inside, the giant squid has a large brain and a complex nervous system, more like what we expect from clever animals such as octopuses. When scientists decoded the giant squid’s genome, they found a big collection of genes linked to building complex brains in vertebrates, hinting that this deep-sea hunter may be far more sophisticated than we once thought.

One species, many mysteries

Old stories imagined many different kinds of giant squid, but DNA work on well-preserved specimens suggests that all known giant squid belong to a single species, Architeuthis dux. Even so, we still have more questions than answers: How exactly do they hunt? How do they raise their young? How do they navigate the deep?

In the last two decades, patient researchers using deep-sea cameras have finally filmed giant squid alive in their natural habitat, and divers in places like the Sea of Japan have occasionally met sick or dying individuals near the surface. Every encounter adds another puzzle piece to the picture.

From “kraken” myth to real conservation story

The giant squid proves a comforting truth about the ocean: sometimes the “monsters” are just animals we haven’t met properly yet. When we trade fear for curiosity, the deep sea changes from a scary blank map to a living library.

So next time you hear the word “kraken,” you can smile and say: that’s a giant squid, a short-lived, fast-growing, deep-sea hunter with dinner-plate eyes and a story scientists are still writing. Out here, the ocean keeps no secrets forever—it simply asks us to look deeper, listen longer, and treat even the strangest creatures with respect.

Sources: BBC Science Focus, Live Science, and current cephalopod research.