The octopus has a few unique defense mechanisms unlike other ocean dwelling occupants, the octopus is not equipped with sharp teeth or poisonous sting rays. They are however exceptionally strong which works to their advantage when capturing their prey.
Octopuses have proven to be highly intelligent. Marine biologists who have studied octopuses determined that have both a short term and long-term memory. There central nervous system in highly developed with half of it residing in their brain and the other half divided among its eight arms. It has also been proven that they feel pain pretty much the same way a human does do their extensive nervous system.
With such a high level of intelligence they only require a few defense mechanisms to survive in the deep blue sea. As they can often outsmart a predator and make a quick escape without having to even use one of their defense mechanisms.
The octopus is also has the ability to grow a new arm. Which is all part of their survival mechanisms. There are over 300 known species of octopuses some of them are very small and would fit in the hand of an adult and some are so large they make a compact size car look small.
Regardless of the size all octopuses have the same defense mechanisms. They have the ability to straighten their body out and become very thin which allows them to escape a potential threatening situation through a small crack in an ocean reef where they spend the majority of their time.
Jet propulsion is another way the octopus can escape predators normally they crawl or swim. When they jet propulsion they straighten their body out and jet quickly through the water. It is not their best defense mechanism but it does work well for them.
Octopuses have the ability to camouflage themselves blending in with their background so potential predators are unable to see them and swim on by. An octopus also uses the camouflage technique to communicate with other octopus especially to warn them of danger.
The most unique defense mechanism an octopus has is called ink sacs. The octopus ejects a thick black cloud of ink which dulls the sense of smell of most large predators such as sharks. The ink also clouds the water so the octopus can escape without being seen.
A very few of the 300 species of octopuses have the ability to transform themselves into more fierce looking marine life such as eels and even sea snakes which often frightens a potential predators.