by Tina Kelly
Eight Arms, Eight Interesting Facts: World Octopus Day!
Celebrating the Giant Pacific Octopus
By Aby Elwood, Educator
This month, on October 8, we will be celebrating World Octopus Day in honour of our octopus ambassadors, past and present! There is no hiding that the giant Pacific octopus is a fan-favourite, so we thought what better way to celebrate these sensational cephalopods than by sharing some of our favourite facts! Here are eight things to know about these intelligent creatures living in the Salish Sea.
The GIANT Pacific Octopus
During the octopus ambassador's time in our Centre, they are usually quite small. But don’t be fooled; this species isn’t called giant for no reason! These animals can reach an enormous size of roughly 9 meters from the end of one arm to the tip of the opposite one, and can weigh up to 20 kilograms!
Blue Blood & Three Hearts
Did you know that all of an octopus's organs are located in their “head”? The mantle is the bulbous, head-like part of the octopus found above their eyes! Within this area are an octopus's three hearts!! Two of these hearts are used for pumping blood to the gills to be oxygenated, and the third is used to pump the oxygenated blood to the rest of the body. We also can’t forget that they have blue blood! This is because the protein in their blood, which carries the oxygen, contains copper instead of iron, giving it a blue colour instead of red like our blood.
Brains, Brains, and More Brains!
If three hearts didn’t impress you, how about nine brains? The giant Pacific octopus has one larger brain in its mantle, used for overall control of the organism. The remaining eight brains are small bundles of nerve cells found at the base of each arm and they are used for control of individual arms. This allows each arm to work independently from one another. This could explain why octopuses are extremely intelligent. Did you know that they are capable of opening jars and are known to be excellent escape artists?
Dedicated Mother
The life span of the giant Pacific octopus is surprisingly short, only living for 3-5 years. However, the end of a female octopus's life is completely dedicated to creating new life. A female octopus can lay roughly 78,000 eggs. The eggs are laid in a rocky den, and during the incubation period (roughly 6-9 months) the mother rarely leaves the den, making sure her eggs are clean and aerated till they hatch. During the incubation period, the mother does not forage for food and slowly starts to deteriorate, this results in the mother dying shortly after her eggs hatch. The giant Pacific octopus makes one great sacrifice to create the next generation of octopuses.
Shell-less Mollusc
The giant Pacific octopus is categorized in Phylum Mollusca; it is related to other animals such as snails and clams. They have calcareous shell but, the octopus does not have a hard outer shell or any shell at all. The only hard part found within the octopus is a chitinous beak, which is used to eat their prey! Their small beak and soft body allows them to fit in the tiniest of spaces. As long as it is bigger than their beak, they can fit!
Venom!
Octopuses use their eight arms and strong suckers to capture their prey and guide it to their mouth. An octopus’s mouth contains a very sharp beak that is used to puncture and tear at their prey. The beak is the dark spot found on the underside of the octopus in the photo on the right. Not only is the beak extremely sharp, it also contains venom. This venom can be very useful when hunting for a meal, as their beak injects the venom into the prey, limiting its movement. This special adaptation allows the octopus to feed on species like crabs without the risk of getting pinched! (Not to worry, this venom has very little effect on humans.)
Messy Eaters!
This carnivorous species enjoys a diet consisting of clams, shrimp, fish and crabs. Here in the aquarium, our octopus's favourite food is red rock crabs. After a yummy meal, the giant Pacific octopus will have a long nap, lasting from 1-2 days. They do not clean up after themselves, instead they leave the shells or exoskeletons of their prey in a heap outside their den. This pile of prey leftovers is called an Octopus's Garden. Keep your eyes out — our octopus ambassador leaves food scraps for you to find!
Did you know that the giant Pacific octopus can change their texture and their colour? They have special cells in their skin called chromatophores. These are specialized pigment cells that allow them to alter their colour and blend in with the surrounding environment. Instead of using a hard shell to protect themselves, they have this stunning ability to camouflage their bodies to hide from hungry predators.
There you have it. Beaks, brains, blue blood, and more! You have learned so much about what makes the giant Pacific octopuses so spectacular. Now you can share all your new knowledge with your friends and family. If you haven’t already, stop by the aquarium to meet our current octopus ambassador, Nanami. Her name means ‘seven seas’ in Japanese, and she has 7.25 arms instead of 8!