Giant Pacific Octopus - Oceana

Cephalopods, Crustaceans, & Other Shellfish

Giant Pacific Octopus

Enteroctopus dofleini


Northern Pacific Ocean from Japan to Alaska and California


Open Ocean

Feeding Habits

Foraging Predator


Order Octopoda, Family Octopodidae


Aside from being the largest of all octopuses, the giant Pacific octopus is also recognizable by its typical reddish-pink color. The octopus is equipped with special pigment cells, called chromatophores, just below the surface of the skin that allow it to change color and blend in with rocky or coral-laden surroundings. Octopuses are actually mollusks—their shells are located in the head as two small plates and the rest of their body is soft. Since they lack a protective outer shell, octopuses like the giant Pacific octopus, use their camouflage abilities to stay safe. When threatened, octopuses can also cloud predators in black ink. The ink is toxic and can be deadly to octopuses if confined to a small space with little current flow. Giant Pacific octopuses spend most of their lives alone. They hunt at night for shrimp, clams, lobsters and fish, but have also been known to eat small sharks using their beak-like mouths to puncture prey.

Along with eight arms, an octopus also has three hearts and nine brains. Two of the three hearts pump blood to the gills, while the third circulates blood to the rest of the body. Octopuses use one central brain to control their nervous systems and a small brain in each arm to control movement. Octopuses, including the giant Pacific octopus, are also known for having blue blood thanks to a copper-rich protein called hemocyanin in their bloodstream, which is efficient for oxygen transport in cold ocean environments.

Giant Pacific octopuses only live an average four to five years in the wild, yet they are still considered one of the longest-living octopus species. Octopuses typically die shortly following breeding. After mating, a female will lay up to 74,000 eggs or more in a deep den or cave and live there for seven months watching over them. During this time, dedicated mothers won’t venture out for food, and shortly after the young hatch, the mother will die. Because of this behavior, it is difficult to know population numbers of the giant Pacific octopus. Even though these octopuses are still commercially fished in both North America and Japan for food and bait, populations have been naturally resilient so far.

Fun Facts About Giant Pacific Octopuses

1. Giant Pacific octopuses can grow to 29.5 feet (9 m) wide from the tip of one arm to the tip of another and 44 pounds (20 kg).

2. Giant Pacific octopuses can change color in one-tenth of a second.

3. Giant Pacific octopuses can be found more than 330 feet (100 m) underwater.

4. Female giant Pacific octopuses never leave their eggs during the brooding process and die shortly after from self-cannibalization.1

5. Female giant Pacific octopuses lay 18,000 to 74,000 eggs that are the size of a grain of white rice.

6. Giant Pacific octopuses have short lifespans of only 2 to 3 years on average.

7. Giant Pacific octopuses have 2,140 to 2,240 suction cups on their arms, giving them a powerful grip and sense of taste and smell.2

Engage Youth with Sailors for the Sea

Oceana joined forces with Sailors for the Sea, an ocean conservation organization dedicated to educating and engaging the world’s boating community. Sailors for the Sea developed the KELP (Kids Environmental Lesson Plans) program to create the next generation of ocean stewards. Click here or below to download hands-on marine science activities for kids.

Kids Environmental Lesson Plans


1 Fisheries and Oceans Canada

2 Monterey Bay Aquarium