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Scientists may have captured the song of a new species of whale living in the Antarctic.

The song can't be identified and doesn't fit the pattern of noise generated by the few known species of beaked whale, raising hopes that it could be coming from a completely new species.

While beaked whales make up the second largest family of cetaceans, relatively little is known about them, mainly because they spend very little time on the water's surface.

Experts are sure the noise isn't made by Arnoux's beaked whales or Cuvier's beaked whales (stock image), because the signal doesn't match

There are 22 species of beaked whale and all of them are elusive deep divers, meaning that they are most often identified by their songs, which they use to navigate.

The mysterious 'Antarctic BW29 signal was recorded near the Orkney Islands, South Shetland Islands, and Antarctic Peninsula by scientists led by Jennifer Trickey of the Scripps Institution of Oceanography, at the University of California, in La Jolla, California.

They have recorded the noise more than 1,000 times to conclude that it's unique in the composition of sounds making the signal and in timing, BBC Earth reported.

'Given that new species of beaked whale are still being discovered, the source of these Antarctic signals might be a species that has yet to be identified,' the study says.

But the song belong to a strap-toothed whale, a southern bottlenosed whale or a Gray's beaked whale (pictured), according to the study, despite the sound being the wrong frequency for a Gray's beaked whale

Experts are sure the noise isn't made by Arnoux's beaked whales or Cuvier's beaked whales, because the signal doesn't match their songs.

But it could belong to a strap-toothed whale, a southern bottlenosed whale or a Gray's beaked whale, according to the study, published in the Journal of Marine Mammal Science.

It is very rare for strap-toothed wakes to be sighted as far south as the noises have been heard, while the noise is the wrong frequency for a Gray's beaked whale, leaving the southern bottlenosed whale as the most likely match.

But again there's a problem, because the whale's relative, the northern bottlenose whale, makes very different calls, leading experts to think that the southern species probably vocalises in a similar way – unlike the Antarctic BW29 signal.

Experts have also recorded an 'Antarctic BW37' signal on six occasions, which is of a higher frequency.

'It remains unknown whether this belongs to a different beaked whale species than the one producing Antarctic BW29,' they write.

Because frequency is usually linked to a whale's size, there is a theory that the Antarctic BW29 song may be made by a southern bottlenose whale, while the higher pitched Antarctic BW37 song could be made by a smaller Gray's beaked whale.

There's also a chance that new species of whale could sing at different frequencies, but this ability would be unique among beaked whale species.

Last year, a study revealed that the shy Cuvier's beaked whale performs the deepest dives made by any mammal on the planet at 9,816ft (2,992metres) below the waves - the equivalent of just under seven Empire State Buildings - and stays below for 138 minutes