Blue Ringed Octopus Behaviour

The blue ringed octopus lives in salt water and is an active carnivore. It is quite territorial and will treat other competitors and rivals as if they were prey.


The blue ringed octopus has a range of defence strategies to use when threatened. These include:

  • small, elastic pigment-filled dermal sacs called Chromatophores which enable the blue ringed octopus to change colour rapidly and in elaborate patterns to mimic the surroundings.

  • the ability to also change the texture of its skin to resemble a variety of backgrounds including sand, rocks and reefs, spiky coral and even seaweed.

  • a small, vestigal ink sac that produces highly concentrated black ink as a globule or as a cloudy stream.

  • advertising the toxicity of blue ringed octopus by displaying iridescent blue rings when it is about to attack.

  • use of jet propulsion to flee an area.


The blue ringed octopus feeds on small crabs, small fish, shrimp and bivalve shells which they hunt for during the day. When swimming, the octopus drifts down towards its prey with all tentacles outstretched and engulfs the prey.If it is on the ground, the blue ringed octopus hides in the background and then glides over and darts at the prey, capturing the food with its tentacles.

The blue ringed octopus is preyed upon by larger fish and other crevice dwellers like moray eels.


In order to move, the blue ringed octopus forces water out through the siphon in a form of jet propulsion. They can also funnel in the opposite direction to swim tentacles first through the water. The blue ringed octopus can also use the tentacles for grasping and pulling themselves along, and for crawling over rocks on the sea bottom.

Website created by Jenny Stevenson - June 2006.