The Pacific octopus can average 45 kilos but can reach weights of 275 kilos, and their arm spans can be up to 6 meters across. Their feed on crustaceans with Dungeness crabs being their favorite meal, but they also eat clams, squid, other species of octopus, and fish. Their dens are built in rock piles and crevasses, they can be recognized by the piles of discarded crab and clamshells around the entrance.
They are generally nocturnal and do their hunting at night. They use their arms, each covered with approximately 200 suckers, to find and hold their prey. Octopus has the ability to subdue prey such as fish with toxic saliva, then they tear into it with their sharp beak. When eating crabs, they simply tear the arms off, then rip it apart and eat the flesh.
The Pacific octopuses can change color at will, to match their surroundings for better stealth.
Their beaks are the hardest hard parts of their bodies and if it fits through a hole, the rest of their body will squeeze through, they can go through some very small openings. They can fit through surprisingly small spaces.
The Pacific octopus has a very sensitive sense of touch with its suckers. The edge of the cups is the most sensitive.
When threatened, octopuses will release a cloud of purple-black ink to confuse the enemy, as they release the ink cloud, their body color will change. Several blotches of ink can be released before the ink sac is empty. The ink is unpleasant for any animal including the octopus itself. If it releases this ink into a cave or crevasse, and it is unable to get out, it could easily die from it. Many aquarium owners will attest to that.