Song Mystery of the Blue Whale

All around the world, blue whales aren’t singing like they used to, and scientists who have been tracking them remain puzzled as to why.

Marine science researchers  Sarah Melnick and John Hildebrand from the Scripps Institution of Oceanography have noticed  that the tonal frequency of blue whales songs is falling every year by a few fractions of a hertz and since the late 1960s have dropped by 31 percent. The researchers track blue whales by using automated song detectors

John Calombokidis, a blue whale expert at the Cascadia Research Collective said that “It’s even more remarkable, given that the songs themselves differ in different oceans. There seem to be these distinct populations, yet they’re all showing this common shift.”

Among the suggested explanations are ocean noise pollution, changing population dynamics and new mating strategies.

Towards the end of this video,(captured from "The Blue Planet" published by BBC), we get to hear some the songs of the blue whale.

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