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Octopus

Invertebrate · Least Concern

Octopus

Octopus cyanea

About

Octopus cyanea, known as the big blue octopus or day octopus, belongs to the family Octopodidae and is found across both the Pacific and Indian Oceans, from Hawaii to the eastern shores of Africa. It reaches a mantle length of about 16 cm with arms extending to at least 80 cm. The species was first described by British zoologist John Edward Gray in 1849, from a type specimen collected off Australia and now held at the Natural History Museum in London.

Family
Octopodidae
Avg size
40-80 cm
Habitat
It lives on reefs and in shallow Indo-Pacific waters, ranging from the Red Sea, the East African coast and Madagascar through Southeast Asia and Oceania, and as far as Hawaii.
Behaviour
Unlike most octopuses, which are nocturnal, this species is active by day, though mainly around the low light of dawn and dusk. It keeps a den, returning there after foraging, whether that is a rock crevice, a sheltered spot beneath an overhang, a hideaway among coral heads, or a hole dug into rubble or sand. As a predator it works the reef for fish, crabs, shrimp and molluscs, eating small catches on the spot and hauling larger prey back to the den.

Where & when

Where & When to See It

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