An octopus uses its arms and suckers to move along the ocean bottom and to capture the small animals that it eats. The suckers can provide enormous suction, enabling the octopus to attach firmly to rocks. If an octopus loses an arm, a new one grows in its place. An octopus's mouth is a beaklike structure located beneath the head at the base of the arms. The life of an octopus.
Octopuses feed chiefly on crabs, clams, and snails.
Many species also eat other octopuses. Certain octopuses make a hole in the shell of their prey and then inject a poison that paralyzes the animals. An octopus has various means of avoiding predators. It can swim quickly backward by forcing a powerful jet of water through its funnel. The octopus may conceal itself by discharging a cloud of inky fluid.