What is a headless chicken monster?
“Headless chicken monster” is a common name for deep ocean sea cucumbers in the genus Enypniastes. Their flowing movements have also earned them the more elegant nickname “Spanish dancers.”
This “headless chicken monster” sea cucumber, Enypniastes eximia, put on a show for our exploration team when it began swimming upon the arrival of remotely operated vehicle Deep Discoverer. Video courtesy of NOAA Ocean Exploration, Gulf of Mexico 2017. Download HD version (mp4, 33.6 MB)
The ocean is full of wonders, but few are quite so striking as the headless chicken monster. Named by remotely operated vehicle pilots for its perceived resemblance to a plucked chicken, this sea cucumber, or holothurian, lives in deep waters around the world and is often seen on deep-sea expeditions.
All sea cucumbers are echinoderms, like starfish and sea urchins. Much like those relatives, most sea cucumbers get where they’re going by crawling along the seafloor. Many sea cucumbers are able to swim, but most only do so as a last resort to escape predators.
The headless chicken monster, though, is different. It and other “swimming” sea cucumbers treat swimming more like a lifestyle than like a last-ditch escape tool. By pulsing its fin-like “flaps,” the headless chicken monster can lift itself off the ocean bottom and swim long distances to find food or escape danger. To eat, the headless chicken monster sinks back down to the seafloor. It extends the tentacles around its mouth, scooping up sediment to feed on organic material called “marine snow” that fell to the seafloor from far above.