Giant Pacific Octopus

(Enteroctopus dofleini)

Habitat and Distribution: Found in rocky areas, caves, and kelp forests in the cold waters of the Bering Sea to Northern California and west to the Sea of Japan.

Size: 10-16 feet long; 22-110 pounds. The largest individual ever caught weighed nearly 600 pounds.

Wild Diet: Clams, crabs, scallops, lobsters, fish, squid, shellfish, sharks, other octopuses, and even birds

Predators: Seals, sea lions, sea otters, fish, and larger octopuses

Reproduction: Breeding peaks in winter. A female mates only once in her lifetime, laying 20,000-100,000 rice-shaped eggs in clusters of 200-300 over a few days. Eggs are laid in strings hanging in a rocky den. The female stays close to her eggs, guarding and cleaning them for up to a year until they are ready to hatch. During this time, she does not eat. Rice-sized larvae hatch from the egg clusters and move to the water’s surface to float for up to 3 months. After this planktonic stage, they settle on the ocean floor and start growing rapidly. They are ready to mate within a year.

Behavior: Giant Pacific octopuses are solitary and often stay in the same den for weeks at a time, leaving only to eat, mate, or escape predation. Their soft bodies are extremely flexible, allowing them to squeeze through narrow passages. To hunt, they may stalk, chase, or ambush prey. Occasionally, they release an ink cloud as a form of defense. They are described by scuba divers as harmless, gentle and curious.


IUCN Status: Not Evaluated

Little is known about Giant Pacific octopus populations. Although this species is sensitive to environmental conditions, they are also very adaptable, which helps populations resist the effects of human threats like overfishing, by-catch, and habitat destruction.

Did you know?

  • Giant Pacific octopuses are usually reddish-brown but can change color when threatened or for camouflage.
  • They have the most complex brains of any invertebrate and are known for their ability to use tools, recognize individuals, and navigate mazes.
  • Each tentacle contains thousands of chemical receptors.