Giant squid (Architeuthis dux) are rare deep-sea invertebrates, which are known mostly through dead specimens that have floated to to surface, washed up on beaches, or met an untimely end in the stomach of a sperm whale. Excitingly, the first video footage shot by humans of a live giant squid swimming at depth (around 900 m below the surface) was filmed earlier this year, and while a snippet has already hit the internet, the full footage is set to air Sunday evening on the Discovery channel (and has been broadcast on a Japanese television program). The short clip that’s already been released shows a graceful creature, gliding in a pitch-black, seemingly empty, ocean. A shot of its body shows its huge eye looking, if I can anthropomorphize the squid for a moment, almost baleful. (Though if I were swimming along in the deep ocean and were suddenly confronted with a submarine with lights, I’d probably look pretty baleful too.)
Giant squid are the world’s second largest largest invertebrates (behind the colossal squid), reaching up to 13 m in length. Much of this length is in the two hooked tentacles it uses to hunt, though there is no part of the giant squid that is not outsized. The tentacles can grow up to ~ 8 m, the arms are a comparatively puny ~2 m, the mantle (ie, the body) can be up to 2.25 metres long.
The eyes are huge too, with a diameter approaching that of a dinner plate. The eyes, like much of the squid’s anatomy and behaviour, is still somewhat of a mystery: virtually no sunlight penetrates down to the depths that the squid lives at, so why does the squid for such a huge eye? It takes an enormous amount of energy to develop such a huge eye, and if there’s no light to be seen, that energy seems like a waste. One of the leading theories is that the eyes are used to detect the light from bioluminescent creatures, especially when they’re dispersing in the path of a sperm whale.
For more on the anatomy and behaviour of the giant squid, it’s hard to do better than this post from Deep Sea News. They also have an excellent link round-up of all things giant squid.
But its impressive physical qualities have enchanted not only scientists and admirers of weird marine creatures; the giant squid has a giant tentacle in the world’s marine lore. The giant squid lives in all the oceans, and is often thought to be the inspiration for the kraken. It’s huge, fearsome (it has hooks on the tentacles!), and lives in a murky world that we have only just started to be able to explore. It’s not surprising that these creatures are cast as the villain in sea-lore, but it’s not like the giant squid is a single-minded creature out for blood. Sure, I wouldn’t want to be on the wrong end of its beak, but I wouldn’t want to be on the wrong end of a killer whale or a leopard seal either. Yet we have children’s movies about orcas, and footage of a leopard seal gently trying to teach a photographer how to hunt penguins was all over the internet a while back. We don’t treat either of them as capital-m Monsters, so why the giant squid? It’s not even at the top of its food chain — while the image of the giant squid and the sperm whale struggling and fighting is culturally pervasive, in reality, the squid doesn’t stand much of a chance against the whale. I have a suspicion that some of the giant squid’s reputation is due to it being an invertebrate: to a vertebrate, land-dwelling species, squids are profoundly weird looking creatures. When humans first came across the giant squid, say in their fishing nets, there was probably not that much context handy for the sailors to make sense of these huge, intimidating creatures. We don’t have much contact with them — we’re only just getting footage of them in their natural habitat! — and we haven’t had time for any sort of image rehabilitation to take hold culturally. This video has gotten a lot of press so far, so it’ll be interesting to see how, if at all, it starts to change our collective perception of these elusive, strange creatures. I’ll update this post when I can find a video of the full Discovery Channel show.
In the mean time, if you’re interested in watching a dissection of a giant squid, the Museum Victoria in Australia has video of the dissection of a giant squid caught in a fishing net off Australia in 2008. It’s long, but the scientists go through the squid’s anatomy in some detail, and it’s well worth the time.