Common Octopus

Common Octopus

  • Scientific name: Octopus vulgaris
  • Size: Maximum mantle length of 20 – 30cm and arm-span of around one metre.
  • Distribution: Found in the Mediterranean and in the warmer waters of the Atlantic. UK population found mostly to the south and west of the British Isles.

Common octopus generally live in rockier areas and in shallow water, under fifty metres deep. They have eight arms each of which has two rows of suckers which have receptors which allow the octopus to taste whatever it is touching. The beak-like mouth of the common octopus is located in the centre of the underside of the octopus’s body. The colour of the common octopus is not fixed and changes to adapt to its surroundings.

Common Octopus Swimming
Common octopus swimming.

The common octopus can move in a number of ways. They can swim slowly using their arms to propel themselves, or use ‘jet-propulsion’ by expelling water from their body to send them forward with more power. When searching for food the common octopus will use its legs to walk along the seabed where it will look for crustaceans and shellfish. The common octopus can pull the shells of these creatures apart with their powerful arms, but they have a much more efficient way of achieving the same result. They grasp the shells in their arms and a toothed cartilage-based protrusion is poked out of their mouths and used to drill into the shells. Fish may also be taken if they can be caught, and will be eaten if they are found dead or dying on the seabed. The common octopus can themselves become prey for larger species such as sharks, cod and bass. The main defences of the common octopus is camouflage, aided by its colour changing abilities and they can swim away from danger surprisingly fast using their jet-propulsion method, and can emit clouds of black ink which disorient and confuse predators.

Intelligence

All octopus species are known to be extremely intelligent – certainly the most intelligent invertebrate species in the world. Common octopus kept in aquariums have been observed performing problem-solving tasks such as unscrewing the lid of a container to access food inside. Common octopus have also been recorded distinguishing the difference between different shapes, and displaying observational learning, proving they have some form of long term memory. In the wild, the common octopus has also been known to steal crabs and lobsters out of pots and then find their way out of the pot, and have been seen using empty shells as a form of protection against predators.

Paul the Octopus

In 2010 a common octopus named Paul came to worldwide media attention when it correctly predicted the results of seven football matches involving Germany at the 2010 FIFA World Cup in South Africa, as well as the result of the final between Spain and the Netherlands. Hatched from an egg in Weymouth Sea Life Centre in England, Paul was then moved to a German Sea Life Centre and had previously correctly predicted four of Germany’s six results in the Euro 2008 tournament. Paul made his predictions by choosing a piece of food (usually a mussel) from two tanks, each of which had the flag of the nations playing attached to it. German fans joking suggested that Paul should be cooked and eaten after he correctly predicted that Germany would be knocked out of the competition by Spain at the semi-final stage.

Paul the Octopus
Paul the Octopus, in his tank with a Germany football boot.

Theories for Paul’s success in predicting the result of football matches varied from pure luck to being attracted to different flag designs, to staff at the Sea Life Centre placing more appetising food in the tank of the team they thought were more likely to win. Paul sadly died a few months after the conclusion of the 2010 World cup at the age of two and a half – the average lifespan for a common octopus.

Commercial Value

Octopus are edible and are caught commercially with an estimated 20,000 tons of octopus being caught throughout European waters every year. British consumers do not have a great demand for octopus, but it is becoming more popular on fish counters and in supermarkets. The common octopus is not thought to be endangered numbers may even be going up in some areas due to the reduction of the number of predators such as cod. The International Union for the Conservation of Nature class the common octopus as a species of Least Concern on a global basis.