Mother Earth home carries many fascinating and unique species in this world. And among them, ocean animals are always elegant and enchanting. The Big Blue is not an exception and it is the largest mammal on our planet which can grow 100 feet long and whose tongue alone weighs equivalent to that of an elephant. They consume small shrimp-like animals called krill and they can consume approximately four tons of krill a day.
The Scientist has found evidence of a new population of blue whales found near Western Indian which reminds us of the quote of Ocean Asha de Vos, a marine biologist where He said that it was a great reminder that our oceans are still this very unexplored place. So, this unknown population of blue whales in the western Indian Ocean was found by the scientist based on sound recordings from that region and this was reported by The New York Times.
Sounds of Big blue:
The big blue is not only the largest but also loudest and it likes to sing at sunset, babble into the night, talk quietly with those nearby, and shout to colleagues 60 miles away. They vocalize at different low frequency sounds typically ranging between 15-40 Hz range and often below the threshold of human hearing. The researchers discovered the blue whale population through their songs. According to a recently published study in the journal Endangered Species Research, each group of whales has its unique distinct song which is different from any other whale song. Until now, only about a dozen blue whale songs each of which acts as a distinct identifier of a unique population has been documented.
What Do These Sounds Mean?
These blue whales use a variety of noises to communicate and socialize with each other. There are three main types of sounds made by whales are clicks, whistles, and pulsed calls. Clicks are believed to be for navigation and for identifying physical surroundings. When the sound waves bounce off of an object and they reflect on them, allowing the whale to identify the shape of the object. Clicks can differentiate between friendly creatures and predators. During social activities, they make use of the Whistles and pulsed calls. More frequent calls are Pulsed calls and they sound like squeaks, screams, and squawks to the human ear. Different vocal “dialects” have been found to exist between different pods within the same whale population. From these whales can differentiate between whales within their pods and strangers.
Their tails and fins would make loud slapping noises on the water surface to communicate nonverbally. The sound can be heard for hundreds of meters underwater and can act as a warning sign for aggression or to scare schools of fish together, making them an easier meal.
The Story of Discovery:
The scientists made this discovery when they were involved in a study where they first recorded the song while undertaking research focused on a pod of Omura’s whales off the coast of Madagascar. It revealed the fact to the researchers that they had discovered a previously unidentified population of blue whales.
“It was quite remarkable to find a whale song in your data that was unique, never before reported, and recognize it as a blue whale,” said Dr. Salvatore Cerchio, who led the analysis of recordings of the whales for this research work. “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.
Listed under endangered species and Hunted to near extinction, the number of blue whales shrank from 250,000 to around 1,000 by the 1950s. There was aggressive hunting in the 1900s by whalers seeking whale oil which lead them towards the brink of extinction. Between 1900 and the mid-1960s, some 360,000 blue whales were killed. After all these events, they finally came under protection with the 1966 International Whaling Commission, but they’ve managed only a minor recovery since then. Also, it was reported that many are injured or die each year from impacts with large ships. But now they have started to recover from their dwindling numbers only recently following a global moratorium on commercial whaling. Scientists use passive acoustic monitoring (PAM) to clarify distribution patterns and enhance conservation and management measures for these endangered whales.
“For twenty years we have focused work on the highly endangered Arabian Sea humpback whale, for which we believe only about hundred animals remain off the coast of Oman,” said Suaad Al Harthi of the Environment Society of Oman. “Now, we are just beginning to explore more about another equally special, and likely equally endangered, the population of the Blue whale.”
The Positive Side of COVID-19:
Owing to the outbreak of COVID-19, earlier this year was pushed to an economic slowdown and reduced shipping traffic. Soon after scientists with the International Quiet Ocean Experiment put together an array of underwater hydrophone listening stations around the world which would give scientists recordings of a glimpse of the ocean with little human interference. “There were no acoustic data from the Arabian Sea prior to our recording effort off Oman, and so the identity of that population of blue whales was initially just a guess,” said the study co-author Andrew Willson from Five Oceans Environmental Services LLC responding to the revelations of this research work. He further added that their work emphasizes that there is a lot more to learn about these animals, and this is an urgent requirement in light of the wide range of threats too large whales related to expanding maritime industries in the region.