The bizarre marines animal was captured on film swimming 3km below the surface of the freezing Southern Ocean.
It was filmed by the Australian Arctic Division (AAD) underwater cameras that were deployed using fishing boats operating in the area.
AAD research scientist, Dirk Welsford, said the team was shocked by the unusual animal that was swimming just off Heard Island.
He said: “We’d never seen this thing before… at the time, none of us actually knew what it was, so we did what a lot of scientists do and googled it.”
It turns out the marine beast is actually a sea cucumber – a brightly-coloured, plankton-eating organism that is roughly the size of a basketball.
Dr Welford said his team dubbed it a ”headless chicken monster” for its unusual appearance.
He added: ”It’s one of the most spectacular specimens I’ve ever seen.
“It’s quite charismatic the way it flies past the camera… and quite unusual that it can swim.
“It does look a little bit chicken shaped and it’s a cool name.
“It’s also a reflection of how little we know about the deep sea and the strange things we see while doing studies down there.”
The oceans in the Arctic and Antarctic have become famous for their strange-looking sea life.
Russian Roman Fedortsov has become famous online after posting dozens of snaps of the bizarre creatures he reels in.