[vimeo width=”680″ height=”420″]http://vimeo.com/26347872[/vimeo]
The broad club cuttlefish living at the Steinhart Aquarium in the California Academy of Sciences are going on six months old and are really starting to show the behaviors of adults. Sometimes known as the Giant Cuttlefish, Sepia latimanus is reported to get up to 50cm long and weight up to 10kg (though I have never seen one in the wild that size), so it makes sense that a hatchling about 1 cm long in February could be almost 18cm in July. Like all cephalopods, these large cuttlefish are eating machines, able to completely eat a silverside in under 2 minutes – with no leftovers at all. They are being fed at least 3 times a day with different feeds, live crabs, live bait shrimp, thawed prawns and thawed silversides.
With the fast growth, some issues start to appear including some minor ‘butt burn’, damage to the tip of the mantle caused by the animal jetting into the sides quickly (a big animal is a strong animal!) and inking events due to adolescent competition. To help alleviate this issues, the population has been split into two groups, 2 on display and 4 in holding. The other adult behaviors are more exciting.
In the video (oh, blue lights and video – why do you hate each other?) you can see a lot of color pulsing on the skin of the cuttles as they hunt for food, today being the first day I have seen them doing it while hunting. It is thought that this striking show is to somehow help in hunting. However, unlike wild adults, the color patterns have not yet reached down the two arms that help give this cuttle the ‘broadclub’ common name as they are stretched out horizontally before the tentacles strike and snare the food item.
The patterns also seem to originate at the back of the mantle, while wide adults seem to pulse more on the head (as shown in the video from NOVA’s ‘Kings of Camouflage’ linked below). The other interesting behavior in the video above is the ‘banding-of-the-eyes-darkening-of-two-arm-tips-while-gesticulating-madly’ behavior (rolls off the tongue eh?), which only seems to occur when the animals are hunting silversides.
As you can tell, I am over the moon with excitement over these cuttlefish behaviors, and even more excited that they are happening with the animals on display. If you are any kind of ceph-head and are in the SF area, I urge you to get down to the academy and take a look as these amazing animals while they are on display.