The surprise trick of coming up behind someone and tapping him or her on the opposite shoulder is a technique that seems to work especially well for the larger Pacific striped octopus.
This is how the octopuses often catch a shrimp for dinner, as you can see from the first video on this page. For a little more emotional drama, watch this same video with a musical soundtrack added by UC Berkeley Campus Life.
The larger Pacific striped octopus seems to be the odd one out, according to recent observations by marine biologist Roy Caldwell of the University of California at Berkeley. Findings reported this month by Caldwell and colleagues in the open-access journal “PLOS ONE” confirm strange stories told about the octopus over the past 30 years — behaviors far different from those of most octopuses.
Two years of observations of live large Pacific striped octopuses in Berkeley laboratories and elsewhere have confirmed behaviors never seen among most octopuses. Activities include unusual beak-to-beak mating, which looks like the animals are kissing; males and females shacking up together, sharing food and having sex for days at a time; and females living long beyond the time they lay their first clutch of eggs, as they continue to eat, mate and lay more eggs.
The paper also discusses the possibility that these odd octopuses may live together in colonies, as observed by scuba divers, and come to recognize each other based on unique color patterns and postures.
As for tapping a shrimp on the shoulder, “I’ve never seen anything like it,” Caldwell told Robert Sanders of Berkeley News, the media outlet for UC Berkeley.
“Octopuses typically pounce on their prey or poke around in holes until they find something,” he continued. “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.”
In addition to Caldwell, authors reporting observations in the paper are Christine L. Huffard of Monterey Bay Aquarium Research Institute; Arcadio Rodaniche of the Smithsonian Tropical Research Institute; and Caldwell, Huffard and Richard Ross, all of the California Academy of Sciences.
The larger Pacific striped octopus is perhaps the oddest of an odd group of creatures, with their shifting octopus shapes, mesmerizing eyes and uncanny intelligence, Richard Ross told Associated Press reporter Seth Borenstein.
“They’re aliens alive on our planet,” Ross said, “and it feels like they have plans.”
MORE VIDEOS FROM THE JOURNAL PLOS ONE
Two larger Pacific Striped Octopuses appear to embrace and kiss in a unique mating ritual.
Sometimes these octopuses move along by bouncing across the bottom of the ocean.
These octopuses can change their coloration along a bilateral line while twirling their arms.