The Day Octopus (Octopus cyanea) is a large octopus species that belongs to the benthic octopus family Octopodidae. It is found throughout the waters of the Indo-Pacific region and it occurs in the warm tropical waters of northern Australia. In Australia it can be found from Moreton Bay in Queensland around the north to Shark Bay in Western Australia. This species is most active during the day and hence this is where its common name was derived from. This octopus likes rocky and coral reefs and it has an excellent ability to camouflage itself with the reef.
This species is known to feed on large crustaceans such as crabs and lobsters and will also eat fish. The Day Octopus is known to lay up to 600,000 eggs that are only 1-2 mm long. An unusual characteristic with this species is that large females have been observed eating the male after mating; this is known as sexual cannibalism. The Day Octopus (Octopus cyanea) has a maximum arm span of approximately 2 metres.
