IAS Gyan

Daily News Analysis

Blue whales



  • Researchers have recorded, reportedly for the first time from the waters off Kerala, the song of blue whales.
  • A hydrophone deployed off Vizhinjam to capture the sounds of migrating humpback whales had instead recorded the call of the endangered blue whale.
  • While humpbacks are known for their high-frequency vocalisations, blue whale songs are a series of short, low-frequency moans.
  • Whale sounds (moans, cries, chirps and cries) are essentially communication tools, for activities such as socialising and mating.
  • Call patterns can vary from population to population.
  • So far, the presence of blue whales in the waters off Kerala have been reported through a few carcasses that beached. But the recording of their calls confirms their presence along this stretch of the western coast.


About blue Whales:

  • The blue whale was once abundant in nearly all the Earth's oceans until the end of the 19th century.
  • It was hunted almost to the point of extinction by whalers until the International Whaling Commission banned all blue whale hunting in 1966.
  • The International Union for Conservation of Nature has listed blue whales as endangered as of 2018.
  • It continues to face numerous threats, both man-made (ship strikes, pollution, ocean noise and climate change), and natural (killer whale predation).
  • The blue whale is the largest known animal to have ever existed.

Pygmy blue whales

  • Though the larger blue whale populations are found around Antarctica where krill, their favourite food, is available, the occurrence of pygmy blue whales is reported in the Indian Ocean.