Ever since humans began exploring the deep sea, plenty of odd noises have been heard underneath the waves. From siren-like wails to a mysterious pinging noise, here are some of the most bizarre (and in some cases, unsolved) noises recorded in the ocean.
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Weirdest noises in the ocean
Bio-duck
Bio-duck can be heard in Antarctic Waters and the West Coast of Australia. It was first reported by submarine personnel in 1960, who thought that it sounded similar to the quack of a duck – although more metallic-sounding.
The mystery of the noise was finally solved in 2014, when a research team (led by Denise Risch) discovered that the sound came from Antarctic minke whales.
No definite conclusions have been made over why these creatures make this call, but it’s hypothesised that it could be due to navigating dense sea-ice areas, mating and feeding.
The Ping
The Ping is a yet-unsolved ‘pinging’ sound that has been heard in the Fury and Hecla Strait, an Arctic channel in Nunavut, northern Canada. It emanated from the seabed in the summer of 2016. Canadian military forces have surveyed the area but nothing has been confirmed as the cause of the noise. However, some scientists have suggested that the noise could be caused by sea ice on the Arctic Ocean rubbing together and cracking.
Biotwang
The Mariana Trench is the deepest known part of the ocean, so it’s no surprise that many significant discoveries have been made there. In 2014, a robotic noise was recorded which puzzled scientists. It was assumed to be produced by a baleen whale, but without visual confirmation this could not be solved. Using visual and acoustic survey data a decade later, a research team confirmed that it was a Bryde’s whale: a particularly elusive baleen whale species.
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Bloop
The Bloop is a ultra low frequency sound detected by the U.S National Oceanic and Atmospheric Administration (NOAA) in 1997. The source of the sound was triangulated to a remote point in the South Pacific Ocean, west of the southern tip of South America.
As the sound was detected by sensors up to 3,000 miles (4,800km) apart, it would have been far louder than any animal noise recorded.
In 2005, the NOAA Vents Program finally attributed the sound to a large icequake, where an iceberg cracks and breaks away from an Antarctic glacier. A similar noise was recorded when Iceberg A53a disintegrated near South Georgia Island in 2008.
52-hertz whale
The 52-hertz whale is known for its unusually high vocalisations: where baleen whales usually communicate at 15-30 hertz, whale song was recorded at 52 hertz. First recorded in the 1980s by the US military in the north Pacific, it has since been dubbed the ‘loneliest whale in the world’.
Marine mammal researcher William Watkins and his team from the Woods Hole Oceanographic Institution tracked the whale for over a decade and published a paper in 2004. It received mainstream media coverage, with many wondering whether other whales could hear it, hence its nickname.
The 2021 documentary The Loneliest Whale: The Search for 52 tracked the 52-hertz whale to the west coast of LA – and provided a potential sighting of a rare blue-fin whale hybrid.
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Upsweep
The Upsweep is an unidentified sound detected by the NOAA, first recorded in August 1991. Almost siren-like, the Upsweep is loud enough to be detected throughout the entire Pacific Ocean. Its source is thought to be in a remote region between New Zealand and the southern tip of South America.
Researchers initially attributed Upsweep to fin whales. However, the sound changes seasonally, which has led scientists to believe it is actually caused by underwater volcanic and seismic activity.
Top image: a fin whale pictured in the Azores.
