The colossal squid

I don’t know how you feel about calamari, but it’s always been a little too rubber-band-like to be one of my favorites.

However you feel about it, though, I’m pretty sure you can agree with me that it’s far better to eat calamari than to have the calamari eating you.

That unsettling prospect was raised recently with discovery of the first nearly complete specimen of the largest known species of squid, Mesonychoteuthis hamiltoni, in the waters near New Zealand.

Up until now, like many people, I thought the so-called giant squid, Architeuthis dux, was the largest. Didn’t Kirk Douglas battle one in Disney’s 20,000 Leagues Under the Sea?

Turns out, though, that this other squid, nicknamed “colossal squid,” is an order of magnitude bigger.

Squids share certain common characteristics: two fins (which give them an arrow-like shape), a mantle (or body), a funnel (through which they squirt water to propel themselves), a head with two eyes and a hard, bird-like beak, eight relatively short arms, and two very long tentacles that end in broader, thicker bits called tentacle clubs.

 

When assessing the size of a squid, scientists, rather than focusing on total length (tip of the mantle to tip of the tentacles), pay more attention to mantle length. The total length of the largest known specimen of giant squid, which washed ashore in New Zealand in 1887, was 16.8 metres, but modern scientists like Dr. Steve O’Shea, senior research fellow at Auckland University of Technology, think its tentacles were stretched out like rubber bands (ah-ha! I knew it!), and it was much shorter in life.

Mantle length is less ambiguous. The 1887’s squid’s mantle was 1.8 metres long. The best current estimate is that the maximum mantle length of giant squids is 2.25 metres; the maximum total length is probably no more than 13 metres.

The new colossal squid specimen, on the other hand, had a mantle length of 2.5 metres, larger than any giant squid so far seen–and it was an immature female, only one-half to two-thirds grown. Based on that, Dr. O’Shea estimates a full-grown colossal squid could have a mantle four metres long. The mantle and fins are also thicker and bigger, respectively, and the eyes, the size of dinner plates, are probably the largest in the animal kingdom.

The circular suckers on a colossal squid’s arms and tentacles contain flesh-tearing hooks; the tentacle clubs have two rows of swiveling hooks.

The existence of the colossal squid has been known since 1925, when two arms were recovered from a sperm whale’s stomach. Until this last specimen, only partial remains had been found, mostly in the stomachs of sperm whales.

It’s not easy to learn about an animal that lives 2,000 metres or more down in the freezing Antarctic and sub-Antarctic, so much of what we think we know about both the colossal squid and the giant squid is based on the study of related species.

For instance, there’s the bizarre (to us, not to the squid) mode of reproduction. Here’s how Dr. O’Shea describes giant squid sex (three words I never before had the opportunity to string together): Two giant squids bump into each other (maybe they find each other through chemicals released into the water, maybe it’s just luck). After a brief moment of panic, they proceed to mate.

The males of some squid species have a modified arm called a hectocotylus for transferring packets of sperm, called spermatophores, to the females. Giant and colossal squids lack this; instead they have a “terminal organ” (more than a metre long in the case of giant squids), which they use to implant spermatophores into the female’s arms. How the sperm gets to the eggs isn’t really known; one possibility is that as the female squid cradles the gelatinous egg mass she produces in her arms, chemicals in it activate the 10-centimetre-long spermatophores, which burrow through her flesh like parasites until they reach the end of her arms, where they explode, releasing sperm directly into the egg mass.

The male, meanwhile, is long gone, and quite possibly missing bits of himself after the violent encounter with the female–or the other male; male giant squid have been found with spermatophores embedded in them. Male squid, it seems, have only two responses to things they bump into: eat it, or impregnate it.

Which is a good reason to avoid bumping into one.

Permanent link to this article: https://edwardwillett.com/2003/04/the-colossal-squid/

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