Watch Gulper’s eel inflate like a terrifying balloon

Since its launch in 2008, the Ocean Exploration Trust’s Nautilus research ship has been carrying a purple ball, a transparent squid and a stunted octopus directly from the ocean floor. The latest bizarre example of marine life that has captured a vessel is a rare gulper eel that acts like a cross between a python and a fox.

As Thrillist reports, this footage was taken by a Nautilus rover wandering the Pacific Ocean at the Papahanaumokuake National Maritime Monument 4,700 meters below the surface. In it you can see a slippery, slippery black creature that looks like it has swallowed a ball on the beach hovering above the seabed. After about a minute, the eel blows its throat, swims around a bit, and unties its jaw revealing a gaping mouth.

The reaction of the scientists on the ship is as much fun as the show that the animals perform. At first they’re not sure what they’re looking at (“It looks like Muppet,” someone says), and after being thrilled by his shape-shifting skills, they conclude it’s a gulper eel. Gulper eels are named after an impressive range of jaws, which allows them to swallow prey much larger than themselves and swell to scare away predators. Because they like to lurk at least 1,500 feet below the surface of the ocean, they are rarely documented.

You can watch the inflated eel and hear the researcher’s response to it in the video below.

[h/t Thrillist]