The Colossal Squid

The Colossal Squid is the biggest invertebrate on the planet. In February 2007 a female colossal squid was caught accidentally by the boat San Aspiring, which was fishing for toothfish in the Southern Ocean. When caught, it measured 26 feet (8 meters) long and weighed about 1,000 pounds (450 kilograms), but scientists believe the species may grow as long as 46 feet (14 meters). The Ministry of Fisheries gifted the squid to the Te Papa museum of New Zealand on 20 May 2007.

The Colossal Squid’s eyes are the largest of any known animal; the size of soccer balls. The squid has light organs (built-in searchlights) on either side of its eyeballs, making it well-equipped to hunt the dark ocean depths. While most squid’s eyes face to the side, the Colossal Squid’s eyes face forwards, allowing it to judge distances when hunting its prey. Each eye has a lens the size of an orange.

The Colossal Squid shoots out its tentacles to snatch its prey. The end of each tentacle is enlarged, forming a ‘club’ lined with two rows of rotating hooks. The harder the prey struggles, the deeper the hooks twist into its flesh.

After making a catch with its tentacles, the squid pulls its prey into its eight outstretched arms. These have an arsenal of hooks and serrated suckers. The arms close around the struggling prey, and move it towards the squid’s mouth. Holding its prey tight, the squid nibbles it into tiny pieces, using its sharp beak, which is like an inverted parrot’s beak. The beak is strong, but the squid can only take small mouthfuls. Its narrow throat passes through the middle of its donut-shaped brain, so a bite too big could cause brain damage!

The Colossal Squid’s enormous round mantle fits over its insides like a bag. The mantle is a bit like a round, heavy, blobby jelly. Really it’s a huge slab of muscle coated in a gelatinous skin. On the skin are chromatophores; cells filled with pigment. If you cut the mantle up, you would get squid rings the size of truck tires!

The Colossal Squid swims forward by rippling its muscular, paired fin. It can also move backwards by shooting water from its funnel. To hover in one place, which it often does, it uses a well-coordinated combination of fin movement and funnel action.