Octopuses Carry Coconuts as Instant Shelters

Octopuses have been discovered tip-toeing with coconut-shell halves suctioned to their undersides, then reassembling the halves and disappearing inside for protection or deception, a new study says. “We were blown away,” said biologist Mark Norman of discovering the octopus behavior off Indonesia. The coconut-carrying behavior makes the veined octopus the newest member of the elite club of tool-using animals—and the first member without a backbone, researchers say.

A team led by biologist Julian Finn of Museum Victoria in Melbourne, Australia, was observing 20 veined octopuses (Amphioctopus marginatus) on a regular basis. The researchers noticed that the animals were frequently using their approximately 6-inch-long (15-centimeter-long) tentacles to carry coconut shells bigger than their roughly 3-inch-wide (8-centimeter-wide) bodies. An octopus would dig up the two halves of a coconut shell, then use them as protective shielding when stopping in exposed areas or when resting in sediment.

To carry the shells, a veined octopus has to stick its arms out and over the edges of the coconut and walk around as if on stilts—making the octopus, while in motion, more vulnerable to predators—study leader Finn explained.

“An octopus without shells can swim away much faster by jet propulsion,” he said. “But on endless mud seafloor, where are you fleeing to?” In other words, a coconut-carrying octopus may be slow, but it’s always got somewhere to hide.

Source: Matt Kaplan for National Geographic News