A colossal squid has joined the giant squid as one of the exhibits in the Natural History Museum’s tours of its spirit collections.
The colossal squid specimen was caught in 2005 off the South Georgia islands in the South Atlantic. It was donated to the Museum by the British Antarctic Survey where it was preserved and prepared for display at the beginning of this year.
The juvenile squid is approximately 2.5m long and includes arms, one tentacle and the head. It would have been much longer, maybe over 5m, if it had its mantle (body) as this takes up half of the squid’s length.
Hooked-shaped suckers on colossal squid tentacles that can rotate, which may help the squid grab and hold on to its prey. © British Antarctic Survey
The public can see the colossal squid, along with the Museum’s 8.62m giant squid ‘Archie’, when they book onto a free Spirit Collection Tour.
These tours in the Museum’s Darwin Centre give visitors a glimpse of some of the 27km of shelves of preserved specimens, such as huge fish, reptiles, deep sea invertebrates and material collected by Charles Darwin himself. Visitors can also find out about the scientific work that goes on behind the scenes.
The Museum’s mollusc collection is huge, around 9 million specimens, but the colossal and giant squids are the largest specimens.
'The only colossal squid parts we had previously in the Museum's collection were from the stomachs of sperm whales, so it was really amazing to add this specimen to the collections and even more exciting to get it on public display,' says Jonathan Ablett, Museum Curator of Mollusca, who unveiled the colossal squid in the BBC's Museum of Life television programme last night.
Having complete specimens is very important as it allows scientists to learn much more about the animal, from obvious things such as what it looks like, to what it eats by looking in its stomach.
DNA from the Museum’s giant squid has already been sent for analysis. Scientists hope to find out information such as how closely related it is to other squid species and if there is more than one giant squid species worldwide.
Jon adds, 'The more specimens of colossal squid we are able to study the more we will be able to learn about this amazing creature and how it lives in its deep sea habitat.'
The colossal squid, Mesonychoteuthis hamiltoni, is possibly the largest living invertebrate. It is thought to reach larger sizes than the giant squid, but a fully grown specimen has, so far, never been found.
They live in the deep ocean at depths of at least 2,200m, which is the main reason finding specimens is so hard. Very little is known about them and what scientists do know often comes from the remains of dead or dying specimens.
Beaks of colossal squids, like this Museum specimen, are often found in the stomachs of sperm whales. © British Antarctic Survey
Beaks of colossal squids are often found in the stomachs of sperm whales, which feed on the squid. This is because the beaks are made of chitin, which means they are not easily digested. Beaks can help scientists to work out the overall size of the animal they came from. They are larger and more robust that the beaks of giant squids.
The heaviest colossal squid ever found was a 495kg specimen caught in 2007 by a fishing vessel in the Ross Sea. This animal had a beak of 42.5mm, and beaks up to 49mm have been found in sperm whales' stomachs.
The colossal squid has the largest eyes of any known living animal, being between 30-40cm. Their eyes face forward, unlike the giant squid whose eyes are on the side of the head. They also have a light organ, photophore, at the rear of the eyeball, possibly to attract prey.
The colossal squid has an impressive 3 hearts, (2 branchial hearts and 1 systemic heart). The branchial hearts pump blood to the gills, where oxygen is taken up. Blood then flows to the systemic heart, where it is pumped to the rest of the body. Squid blood is blue, not red as in humans. This is because squid blood contains a copper-containing compound called haemocyanin.