Rarely seen ‘shape-shifting’ whalefish spotted off the coast of California

‘So many mysteries remain regarding these remarkable fish,’ researchers say

A bright orange, female whalefish was filmed gliding through the water by researchers (Twitter/ MBARI)

An elusive “shape-shifting” whalefish has been spotted off the coast of California in a rare sighting of the unique deep-sea creature.

A bright orange, female whalefish was filmed gliding through the water by a remotely operated vehicle (ROV), the Monterey Bay Aquarium Research Institute (MBAR) said on Twitter.

A clip of the unique fish shared by the institute showed it shifting through the water in the dark depths of the ocean.

Researchers explained that the female fish was encountered by a team at the institute 2,013 meters deep offshore of Monterey Bay.

Sightings of the fish are a unique spectacle, as the creature typically lives below the ocean’s surface in the mysterious depths of the deep sea.

“Whalefish have rarely been seen alive in the deep, so many mysteries remain regarding these remarkable fish,” MBAR said on Twitter.

It added: “With each deep-sea dive, we uncover more mysteries and solve others.”

The researchers said that they have only encountered this obscure group of fishes 18 times in 34 years of deep-sea exploration through the use of ROV’s.

In another clip, the institute explains that the unique fish have tiny eyes and use the vibrations in the water around them to find their way about their environment.

The deep sea swimmer was first discovered in 1895 by two Smithsonian scientists.

From this point on, the fish became part of a mystery that stretched decades, before scientists worked out that three different physical forms of the fish are all part of the same family.

The fish essentially shapeshifts into completely different body types following infancy depending on whether it is a young fish, male or female.

The Smithsonian Institution explains that tapetails are the young or larvae form of the fish. They use their upturned mouths to eat small shellfish.

The male versions of the fish are called bignose fish. They feed directly off their huge livers and use their large nasal organs to detect females.

Female whalefish use their gaping mouths to capture large prey and are said to grow much bigger than the male fish.

Their bright orange colour makes them invisible in the deep ocean as these colours of light can’t be detected in such deep water, LiveScience reports.