Predators of the octopus include eels, dolphins and sharks, among others. Octopi have many means of deterring predators, including the ability to detach an arm if it is in a predator's grasp and ink glands to release clouds of black ink and block the view of attackers. An octopus can also deliver venomous saliva by biting its prey.
The octopus has a soft body that lets it squeeze into small crevices and cracks to evade predators. It is also a fast swimmer that can expel water through its mantle to propel itself quickly away from danger. One of its most powerful defense mechanisms, however, is its ability to camouflage itself to fit in with its surroundings so that predators don't notice it.