Octopuses crawl when they can swim because their cardiac systems don’t operate at full capacity. Although an octopus has three hearts, only two of them beat while they are swimming. This is because two of the hearts are used to pump blood to the octopuses’ gills, while the third heart is reserved for circulating blood to the organs only.
Since their two hearts are not pumping as much blood throughout their bodies as they would normally, octopuses can become fatigued while swimming. Crawling conserves their energy while still allowing them to travel through the water.
More about octopuses:
- An octopus can squeeze into a small opening that accommodates its beak – for instance, 50 pound (22.68 kg) octopuses have been known to fit through 2 inch (5.08 cm) holes.
- Two-thirds of the nerves in an octopus are located in its arms, rather than its brains – this is necessary to enable a protective mechanism that prevents its eight arms from tangling or the suckers on its limbs from sticking together.
- Octopuses will eat their own species – giant Pacific octopuses regularly kill and consume smaller octopuses.