Noc: The Talking Beluga Whale

   I'm sure most people noticed the newspaper articles back in October on the talking beluga whale called Noc. I thought a quick recap of this study was warranted, as The Guardian has named this one of their 'Top 10 wackiest environment stories of 2012'.

A beluga whale filmed wild in Alaska; source.

    This followed the study published in Current Biology by Ridgway et al., 2012, concluding that a beluga whale kept at the National Marine Mammal Foundation in San Diego had learned how to modify sounds to make them more human-like. Apparently this sounded so convincing it fooled a diver into thinking someone had yelled to get out the water; surfacing and calling "who told me to get out?". Ridgway et al., 2012, recorded and analysed these sounds, determining that they were several octaves lower than regular calls, and demonstrate "spontaneous mimicry of the human voice, presumably a result of vocal learning".

Figure 1 from Ridgway et al., 2012, demonstrating acoustic
similarities between human vocalisations (A) and Noc's vocalisations (B).

    The researchers have therefore interpreted Noc's unusual vocalisations as an attempt to mimic humans, due to the presence of human keepers and divers. They found that Noc's vocalisations had an amplitude rhythm similar to human speech (as in figure 1 above); vocal bursts were also similar, averaging around 3 per second.

    Noc has remained vocal, but stopped demonstrating speech-like behaviour after he matured. Vocalisations similar to human speech have also been recorded in white (beluga) whales in the wild, however Ridgway et al., 2012, note that Noc was not a 'good mimic' compared to well-known mimics like parrots. Although it does seem clear that a close association with humans can produce definite behaviour of vocal learning in other species.

A video of the human-like sounds Noc produces.