The secret and unusual sexual and hunting behaviours of the Pacific striped octopus have been observed for the first time in captivity.
The rediscovered tropical octopus subtly taps its prey on the shoulder and startles it into its arms.
Other different moves include beak-to-beak mating and pairs who live together, according to a study of the octopus published in the journal PLOS ONE.
“I’ve never seen anything like it,” says marine biologist Roy Caldwell, a University of California, Berkeley, professor of integrative biology.
“Octopuses typically pounce on their prey or poke around in holes until they find something. When this octopus sees a shrimp at a distance, it compresses itself and creeps up, extends an arm up and over the shrimp, touches it on the far side and either catches it or scares it into its other arms.”
The larger Pacific striped octopus, unlike their more common cousins, also turn out to be very social. They have been seen in groups of up to 40 off the coasts of Nicaragua and Panama.
Usually male octopuses share sperm with females at arm’s length, leaving room to flee in case the female gets aggressive or hungry.
However, the striped octopus sometimes cohabit in the same cavity for at least a few days while mating, with little indication of aggression.
Mating pairs have even been seen sharing meals in an unusual beak-to-beak position.
When having sex, they grab each other’s arms sucker-to-sucker and mate beak-to-beak.
“There are a lot of species of octopus, and most have never even been seen alive in the wild and certainly haven’t been studied,” he said.
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