While navigating the waters of the Southern Ocean in 1960, in Antarctica, the crew of a submarine heard a particularly strange sound: a duck-like quacking. But this sound was so powerful that it would require a duck the size of a giant squid to produce it. The crew reported it to the authorities and named it the Bio-Duck.
Lacking a better explanation, the name stuck. For decades, this sound, also heard off the coasts of Australia and New Zealand, would be considered one of the greatest mysteries of the oceans.
Strange Ducks As noted by the Science Alert website, however, the Bio-Duck was identified in 2014 as being produced by Balaenoptera bonaerensis, also known as the Antarctic minke whales. Using tracking tags, research teams were able to correlate the presence and movements of these whales, which measure between seven and ten meters, with the recording of the Bio-Duck. Although it was neither the call of an unknown species nor a sound from the depths of Hell, as some have speculated about other unexplained noises, the mystery of the Bio-Duck does not end there. Far from it.
A mystery far from being solved
First of all, the Bio-Duck has a cousin: the Bio-Goose, another sound similar to that of poultry. What’s more, both sounds are sometimes heard without any documentation of the presence of Antarctic minke whales in the area. This has intrigued the teams of Ross Chapman, an oceanographer at the University of Victoria in Canada, who has been studying the subject since the 1980s.
In presenting his work at the 187th meeting of the Acoustical Society of America, the researcher suggested that it might be possible for another animal to produce this sound. But which other marine leviathan is capable of communicating through this strange duck-like quacking, with frequencies between 60 Hz and 100 Hz and intervals between each sound ranging from 1.6 to 3.1 seconds?
An inexplicable underwater dialogue
For Ross Chapman’s team, this is indeed a dialogue. « We discovered that there were usually several different speakers in different parts of the ocean, and they all made these sounds, » explains the scientist during his presentation. He continues:
The most surprising thing is that when one speaker was talking, the others stayed silent, as if they were listening. Then, when the first speaker stopped, they listened to the responses from the others.
The final mystery: whether it’s the Balaenoptera bonaerensis or other cetaceans, no one knows what these exchanges are about. « It’s a question that has never been solved in my mind, » says Chapman. « Maybe they were talking about dinner, maybe they were parents talking to their children, or maybe they were just commenting on that crazy ship that kept going back and forth with a long rope trailing behind it, » he concludes.
Source: GEO
