Mysterious Sounds Coming From the Depths of the Southern Ocean Continue to Astound Scientists

In the early 1980s, several experts captured mysterious quaking sounds coming from the depths of the Southern Ocean (Antarctic Ocean). For decades researchers have been trying to nail down the origin of what they believe to be four strange, short tones, The Independent reported.

Around 2014, scientists presented some evidence claiming that the sounds could be coming from Antarctic Minke Whales, but other marine scholars believed that more proof was needed to validate this claim. Analysis continued and recent outcomes suggest that these sounds are full-fledged conversations between the mammals.

The sounds were initially heard in the 1960s and first recorded in 1982 during a soundscape analysis of the South Fiji Basin, Smithsonian Magazine reported. The noises were given the moniker 'bio-duck' because of their short quack-like pattern. To this date, the sound reverberates all through the Southern Ocean. For decades these oddly-mechanical sounds were considered to be the biggest mystery of this region.

Ross Chapman, a researcher at the University of Victoria in Canada joined the ongoing analysis regarding the 'bio-duck' in 1986 with NOAA, Duke University, and other groups. They examined the data collected during the soundscape analysis and speculated that the 'mechanical' sounds could be the work of marine beings in the ocean. "We discovered that the data contained a gold mine of new information about many kinds of sound in the ocean, including sounds from marine mammals," Chapman explained.

Building on their research the experts placed acoustic recorder tags on two Minke Whales in the Southern Ocean to document their sounds in 2013, Smithsonian Magzine reported. The data showed them that the 'bio-duck' was very similar in texture to some of the sounds produced by Minke Whales. Despite this evidence, other marine scientists were hesitant to consider the assertion as conclusive, because there was no visual confirmation. 

Chapman and others continued to work on the research and found more specifications regarding the mysterious noise, The Independent reported. The new findings were presented in the virtual 187th Meeting of the Acoustical Society of America.

Researchers noted certain repeatable patterns in the sounds, which led them to believe that it could be conversations between multiple animals rather than an isolated affair. Considering that the assertion regarding the Minke Whales is still up for debate, the subjects as of now can be a multitude of beings.

"The sound was so repeatable, we couldn’t believe at first that it was biological," Chapman explained. "But in talking to other colleagues in Australia about the data, we discovered that a similar sound was heard quite often in other regions around New Zealand and Australia."

Their assertion about it being a conversation came from observing the 'discussion' that was going down between the different animals, Smithsonian Magazine reported. "The most amazing thing was that when one speaker was talking, the others were quiet, as though they were listening," Chapman explained. "Then the first speaker would stop talking and listen to responses from others."

This new finding adds to the 2014 study, and researchers believe there is still a lot more ground to be covered regarding the analysis of 'bio-duck'. "The question is: When do they make the bio-duck sound, and why do they make it?" Chapman said. "I wouldn’t say that the answer is really known, even today."