Giant Pacific Octopus (Enteroctopus dofleini)

Description: Although it is the largest octopus in the world, the giant Pacific octopus is a rare find at Haystack Rock. The giant Pacific octopus is usually dark red or brown-red but can change color almost immediately to camouflage with its environment. These creatures can have arms that reach at least 2 m across but frequently exceed 4 m in length. They have eight equal sized arms and each of these arms has round suction cups on it that the octopus uses to grab prey!

Habitat: Geographically, it is found on both sides of the Pacific ocean; it can be found from Alaska to northern Mexico in the eastern Pacific, and on the other side of the Pacific it can be found around the Korean Peninsula, Japan, and Siberia’s coastlines. While rare in the tide pools, they can be found in the low intertidal but are more common in the subtidal and may even reach depths of 1,500 m deep!

Diet: Giant Pacific octopus prey heavily on clams, crabs, and other mollusks. With a lot of their food having shells, they use their sharp beaks to bite into the shells or their strong suction cup lined arms to pry open the shells. If that doesn’t work, they can use secretions in their saliva to soften the shell and their radula to scrape away a small hole. Their predators include seals, sea otters, large fish, and sharks.

Tide Pool Tidbits:

• Being the largest octopus in the world is even more impressive knowing they hatch from an egg the size of a grain of rice!

• The only hard part of an octopus’s body is its beak (which is located in its mouth and looks similar to the beak of a parrot). The rest of its body is very soft. Therefore, an octopus can fit its entire body through tiny holes as long as its beak is smaller than the hole!

• Although this is the most common type of octopus seen at Haystack Rock, occasionally an east Pacific red octopus (Octopus rubescens) has been found.

References: The New Beachcomber’s Guide to the Pacific Northwest by J Duane Sept, Monterey Bay Aquarium