For decades, a sound dubbed by submarine crew in the Southern Ocean as ‘bio-duck’ perplexed researchers from the world over.
First spotted in the early 60s, this mysterious underwater sound mimicked the call of a duck and it seems after decades of research its origin has been finally traced.
The extremely rare and elusive Antarctic Minke whale is the one responsible for these duck-like calls. While monitoring and studying these giants in the cold Southern Ocean and the harsh weather of Antarctica is hard, latest technology has enabled marine biologists to delve deeper than ever before.
Denise Risch from the National Oceanic and Atmospheric Administration’s (NOAA) Northeast Fisheries Science Center (NEFSC) says that the use of “passive acoustic monitoring” has finally helped them in tracing the origin of this unique underwater call.
Heard mainly during the austral winter in the Southern Ocean and off the Western Coast of Australia, there is plenty still left to be unraveled about the bio-duck call.
With Minke whales hard to spot during the short daylight hours of Antarctica, the new find will help researchers trace them acoustically even during the dark winter months.
The bio-duck sounds come in sets spaced about 3.1 seconds apart. Risch speculates that the whales might be using this sound either for breeding or for navigation.