The Mariana Biotwang
Near the deepest point on Earth, underwater microphones picked up a strange sound: a low grunt followed by a metallic twang.
What was reported
In 2014, ocean gliders carrying underwater microphones near the Mariana Trench in the western Pacific recorded an unusual sound lasting a few seconds: a deep moan followed by a high, metallic twang, almost like a sound effect from a science fiction film.
Researchers named it the 'Western Pacific biotwang', suspecting an animal, but couldn't identify it, and it became one of the ocean's best-known mystery sounds.
Explanations offered
In 2024, scientists matched the sound to Bryde's whales, after recording biotwangs at the same time as they saw the whales during research voyages. They then used artificial intelligence to find the call in years of earlier recordings, tracking the whales' movements across the Pacific.
- When
- Recorded since 2014; identified in 2024
- Where
- Mariana Trench, Western Pacific
- Witnesses
- Underwater recorders and scientists
- Status
- Explained
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