Recording has shocked researchers

A recording of a Belgua whale named NOC mimicking human speech has shocked researchers in the U.S.A.

NOC copied the sound of human speech so well that researchers thought they were humans conversing in the distance, and a diver working with NOC at one point left the water and asked who had told him to get out.

A paper has now been published in Current Biology which reveals an amplitude rhythm in NOC's vocalisations that was comparable to human speech, and that fundamental frequencies were in the same range as human speech and several octaves lower than the whale's usual sounds.

It also took considerable effort for the whale to make the sounds, as it involved carrying the pressure in his nasal tract while making other muscular adjustments and inflating the vestibular sac in his blowhole.

Lead author of the study, Sam Ridgeway of the National Marine Mammal Foundation, said: "The whale often heard divers talking over underwater communication equipment. I think that vocal animals like feedback. Perhaps this figured in his motivation."

He added: "We trained the whale to interact with us acoustically for hearing test and for reaction time determinations, among other things. For this new work, the whale was responding to us vocally. These responses may have limited his interest in the human speech-like sounds."

NOC stopped making the sounds after he was about 3 or 4 years old. The research was conducted many years ago, but has only recently been published.

To hear NOC, click here.