Many of the eggs will die if not tended by the female until hatching. The young then settle to the bottom, although not much is known about this settlement phase. Dens are an important resource to octopus during all benthic life stages. Dens are used both as brooding chambers and as refuges from predators, including other octopuses, various fishes, and many marine mammals. Most dens of juvenile E. dofleini are naturally occurring spaces under rocks or in crevices or are an excavated cavity in sand or gravel under a boulder.
Octopuses consume mostly crustaceans and mollusks, most often small crabs and scallops.
Other bivalves, snails, fish and other octopus are also eaten. Through this hole, the octopus secretes a toxin that paralyzes the prey and begins to dissolve the connective tissue. The prey is then pulled apart and consumed. The third right arm of the male octopus is hectocotylized with a modified tip, called the ligula, that is used during mating, and in E. dofleini may be one fifth the length of the arm. The mouth is located at the center of the arms.