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Video courtesy of the Monterey Bay Aquarium Research Institute

This deep-sea octopus is a jellyfish junkie

Jellyfish can be a menace to beachgoers and a threat to fisheries, but for some oceangoing species, they’re a meal. Even though jellyfish are mostly just blobs of low-calorie gelatin—think Jello minus the sugar—scientists are discovering more and more predators, from vampire squid to tuna, noshing on the tentacled beasts. Now, scientists are adding the giant deep-sea octopus Haliphron atlanticus to the list of jelly connoisseurs. Little is known about deep-sea food webs, so researchers using remotely operated submersibles in 2013 were excited when they spotted three of these mysterious creatures off California and Hawaii holding jellyfish remains in their arms (above; see the full video here). The jellies’ arms and reproductive organs, which contain most of their nutrition, were missing, suggesting they had already been gobbled up. And because the octopuses were holding the jellyfish from behind, scientists think they might have been using their prey’s stinging tentacles to catch more food, a trick employed by at least two other species of octopus. Back on land, the scientists took a trip to the Hamburg Zoological Museum in Germany to investigate the stomach contents of five preserved H. atlanticus specimens. Their findings confirmed that these 4-meter-long octopuses do indeed eat jellyfish. And because H. atlanticus is, in turn, eaten by large fish, blue sharks, and even sperm whales, jellyfish are an important part of the ocean’s food web.