The octopus

18/03/2020
Natalie H.
  • Mediterranean octopus

The octopus is one of the marine species that always makes much illusion to see during a dive. It is curious that when you travel to places where the seabed is covered with coral reefs, this species is almost impossible to see. Tourists who come to dive on our shores love to see octopus, a species that we don’t give much importance to, I guess for the ease to find several in a dive.

But let’s find out something else about octopus!

The life of an octopus is short, can live between 6 and 18 months and is limited by its reproduction: males can only live a few months after mating and females die shortly after hatching their eggs.

The adult males look for females, and once found, will fight with other individuals in order to fertilize it. The female will hide in a hole or crack, placing stones in front to use as protection. For 2 months the female will not leave her lair and will protect the eggs she has placed on the roof of her house. It is possible that the female, by not eating during this period, will end up dying when the new offspring are born. This moment is in the spring. The best time for your observation is from March to June.

Some specimens can weigh up to 10kg and measure up to 1 meter, although those we can observe are not so large.

Their enemies are Moray eel, conger and Common dentex. It is normal to see males with one of their 8 legs cut or even all! for attacks by their predators. 
The rectal gland of these molluscs has been transformed into an ink gland, which produces a secretion that is stored in a sac below the digestive gland. The bag is close enough to the siphon for the octopus to eject the ink with a jet of water.   The ink of an octopus is not poisonous and it is simply used to disorient its attackers and to escape.

Benthic octopus (which live at the bottom of the sea) usually move between rocks; locate the prey by groping through the cracks or thanks to their magnificent vision and they can attack by throwing themselves propelled by a jet of water emitted by their siphon on a prey and pull it towards the mouth with their arms holding it with the suction cups. Small prey can be completely trapped by the webbed structure between their arms. They usually inject crustaceans like crabs with paralyzing saliva and then chop them up with their mouth, which is called a beak, because of its resemblance to a parrot’s beak.