A video taken during a dive in Lembeh Strait, Indonesia, shows an aggressive coconut octopus walking across the ocean floor with the bivalve shell it uses for protection and lurching at the person holding the camera.
The octopus's behaviour in the video resembles another octopus we wrote about in 2015, which carried two halves of a coconut shell across the sea floor. Since an octopus is unprotected when it hunts prey, a shell can provide more safety, even if it's cumbersome to lug around. In addition to camouflage and ink-squirting, behaviour like this shows the creativity that allows octopuses to survive in the ocean without a hard outer shell.
The momentary pauses in the octopus's movements also allow viewers to see the details of its body, from the brown mantle that resembles a vein-covered sack to the pure white underside where its arms connect to its body.
Fredrik Moberg, the person who took the video of this octopus, says he had a metal stick that he used to mimic animal movement under the sand in front of the octopus, which was hiding in the shell.
"It was almost instantly interested by the movement, and came out [of the shell]," he says. "After that it kept on lunging forward."
He is unsure whether the bright lights caused the octopus to continue lunging at him, but he had no direct contact with the octopus during the encounter.
WATCH: COCONUT OCTOPUS GIVES BIRTH TO THOUSANDS OF BABIES