Scientists discover ghostly new fish in the depths of the Pacific

11 Sep 2018

A CT scan of one of the new fish discovered by scientists. Image: Newcastle University

Three new species of fish have been discovered in the Atacama Trench in the Pacific Ocean.

Scientists from 17 different nations have captured rare footage of what is believed to be three new fish. For now, the three fish are known as the Pink, the Blue and the Purple Atacama Snailfish. They will likely soon receive academic monikers following further study.

Part of the Liparidae family, the fish are unusual in appearance compared to the typical idea of a deep-sea fish. Instead of menacing jaws and a hefty frame, the three types of fish found are small, translucent and have no scales to speak of.

Adapted to the deepest waters

One of the researchers, Dr Thomas Linley from Newcastle University, said that the snailfish family is particularly suited to living in the dark depths of the ocean. “As the footage clearly shows, there are lots of invertebrate prey down there and the snailfish are the top predator; they seem to be quite active and look very well fed.

“Their gelatinous structure means they are perfectly adapted to living at extreme pressure and, in fact, the hardest structures in their bodies are the bones in their inner ear, which give them balance, and their teeth.

“Without the extreme pressure and cold to support their bodies, they are extremely fragile and melt rapidly when brought to the surface.”

Researchers examining the new fish closely

Due to their remote habitat, the fish are free from competitors and predators. The researchers were able to catch one of the new species, which followed its prey into one of their traps. The fish is currently being described by the researchers from the Newcastle team as well as colleagues from the US and the Natural History Museum in London.

The Atacama Trench is almost 6,000km long and is part of the Hadal Trenches, one of the last unexplored areas of our planet’s oceans. The trenches are mostly located around the Pacific Rim in areas where tectonic plates collide and plunge. They reach depths close to 10,000 metres in certain areas. The Atacama runs along the west coast of South America.

How did they make the discovery?

Scientists and engineers have been working on technology to aid the exploration of the area for five years and have completed nearly 250 deployments to date.

The equipment used, called a ‘lander’, includes a HD camera and traps and is dropped overboard, free-falling to the ocean floor. Once it arrives, it monitors and samples the environment.

On this expedition, the team deployed their baited camera system 27 times. More than 100 hours of video and 11,468 photographs were taken at the seabed.

As well as the new fish, the researchers also filmed footage of long-legged isopods known as Munnopsids. “These crustaceans have small bodies, extraordinarily long legs and swim backwards and upside down, propelling themselves with paddles on their ventral side – their ‘tummies’ – before righting themselves on the seafloor and spreading their long walking legs out like a spider.”

Ellen Tannam was a journalist with Silicon Republic, covering all manner of business and tech subjects