In the waters surrounding Antarctica several decades ago, people heard a peculiar sound: a repetitive noise resembling the quacking of a duck, if that duck were a giant “octopus.” This mysterious ocean sound, first reported in 1960 and dubbed the “Bio-Duck,” puzzled scientists for years. A recent analysis suggests that the source of this sound appears to engage in conversational exchanges.
Ross Chapman, an oceanography researcher at the University of Victoria in Canada, explained, “We found that there were usually multiple sound sources in different parts of the ocean, all producing these sounds. The most astonishing thing was that when one source made noise, the others remained silent, as if listening. Then, the first source would stop, and the others would begin to respond.” Chapman presented these findings at the 187th Meeting of the Acoustical Society of America.
In 2014, researchers using animal-attached recording devices associated the Bio-Duck sound with the Antarctic minke whale (Balaenoptera bonaerensis). These whales emitted sounds similar to the Bio-Duck recordings. However, similar sounds recorded in other oceans around Australia and New Zealand have not been linked to any observed animals, indicating that other cetaceans might produce Bio-Duck-like sounds.
Chapman, who has been studying the soundscape of the Southern Ocean since the 1980s, noted that the repetitive nature of the sound initially led researchers to doubt its biological origin. Over time, as more data were analyzed, it became clear that the sound was indeed produced by an animal.
Despite identifying the Antarctic minke whale as a source, the purpose of these sounds remains unknown. Chapman believes the recordings indicate conversational exchanges, but the content of these “conversations” is still a mystery. He speculates, “Perhaps they were discussing dinner, maybe parents talking to their offspring, or perhaps just commenting on that strange ship passing by, towing a long cable behind.”
Future research may shed light on the true nature of these enigmatic underwater communications.