The Very Cold, Very Dark & Very Deep Home of the Mysterious Snailfish

Researchers from the University of Western Australia and Japan have plumbed the depths – five miles of depth – to spot and film the deepest fish ever seen. 

Using a remotely operated submersible in the Izu-Ogasawara Trench not far from Japan, the scientists spied a snailfish at a record-breaking 27,349 feet deep. The species is unknown, but it likely belongs to the genus Pseudoliparis.

“The Japanese trenches were incredible places to explore; they are so rich in life, even all the way at the bottom,” said UWA Professor Alan Jamieson, founder of the Minderoo-UWA Deep Sea Research Centre and chief scientist of the expedition. “We have spent over 15 years researching these deep snailfish; there is so much more to them than simply the depth, but the maximum depth they can survive is truly astonishing.”

At these depths it is cold, dark, and the pressure is bone-crushing. The snailfish can withstand the pressure – 800 times the pressure at sea level – because they have evolved without swim bladders, air-filled sacs that most fish possess for buoyancy. Instead of scales they have a gelatinous layer that further protects them from the crushing depths.

Watch some of the bottom-dwellers in motion here.

Photo credit: University of Western Australia