We may have missed something colossal that was present here the entire time.
Scientists have recently discovered a previously unknown population of blue whales present in the western Indian Ocean based on analysis of sound recordings from the region, found a New York Times report.
The discovery of the group of whales, described in a paper published in the journal Endangered Species Research, mentions the species has its own signature anthem. The anthem compromises of a slow, bellowing ballad that’s distinct from any other whale song ever described.
“It was quite remarkable," said Dr. Salvatore Cerchio, Director of the African Aquatic Conservation Fund’s Cetacean Program and Visiting Scientist at the New England Aquarium, who led the analysis of recordings, “to find a whale song in your data that was completely unique, never before reported, and recognize it as a blue whale." Blue whale song has been extensively studied globally, and several blue whale populations have been identified based on their distinct songs throughout the Indian Ocean.
“With all that work on blue whale songs, to think there was a population out there that no one knew about until 2017, well, it kind of blows your mind," Cerchio said.
The published study also concluded that, “if there is a northern Indian Ocean subspecies, it is likely this population. Moreover, the potentially restricted range, intensive historic whaling, and the fact that the song-type has been previously undetected, suggests a small population that is in critical need of status assessment and conservation action."
The find is “a great reminder that our oceans are still this very unexplored place,” Asha de Vos, a marine biologist who has studied blue whales in the Indian Ocean told New York Times.
Not much is known about blue whale songs, although most researchers think that they help males woo their mates, as is the case with closely-related species.
Whale song has been described as a composition of moans, snores, chirps and cries. They are all below 4 kHz in frequency. Blue and fin whale songs are so low in frequency that parts of them are inaudible to humans. Humpback whales produce the most complex song of the lot. It consists of repeated phrases arranged in themes in a hierarchical structure, and can last from 6–35 minutes. Individual whales have been found to sing for up to 22 hours, repeating the song over and over again, describes journal Current Biology.
Blue whales were hunted to near extinction around the globe during the 20th century, and populations have only started to recover very slowly over the past several decades following the global moratorium on commercial whaling.