By asahifile 
Strange “Biotwang” Identified as Bryde’s Whale Call
Exploring the Ocean’s Unique Vocalizations
In recent marine biology research, scientists have unveiled the true identity of a peculiar whale vocalization identified as the “biotwang.” This unusual sound, first detected during an acoustic survey of the Mariana Archipelago in 2014, combined both low- and high-frequency elements that set it apart from typical whale calls. Researchers now believe that it originates from Bryde’s whales (pronounced “broodus”), specifically, a species of baleen whales. This discovery opens new avenues for tracking whale populations and their migratory behaviors, as outlined in a recent publication in Frontiers in Marine Science.
Background of the Biotwang
The biotwang was first noted in 2014 when the autonomous monitoring system recorded what seemed like a mechanical whale call. The complexity of the sound, lasting roughly 3.5 seconds and ranging from around 30 Hz to a piercing 8,000 Hz, led to initial confusion about its origin. Experts from NOAA Fisheries, including scientist Ann Allen, attributed the strange noises to baleen whales but could not confirm their hypothesis without accompanying visual evidence.
A Collaborative Approach
Fast forward to a collaborative effort in 2018, Ann Allen and her team implemented visual surveys in the Mariana Archipelago alongside acoustic data collection. Over the course of their survey, they observed ten distinct Bryde’s whales and recorded the biotwang sound in nine instances, conclusively tying this vocalization to the species.
Purpose of the Biotwang Call
The exact function of the biotwang call remains uncertain. As Allen explains, baleen whale vocalizations can serve various purposes, including breeding communication and contact calls. The team hypothesizes that the biotwang could be a form of contact communication, akin to a “Marco Polo” call-and-response mechanism among Bryde’s whales. Further research will be necessary to validate this theory.
The Role of Machine Learning
Crucial to this research was the application of a machine-learning model designed to analyze over 200,000 hours of whale recording data. Initially adept at identifying humpback whale songs, the model was adapted to include the biotwang sound thanks to collaboration with Google data scientist, Lauren Harrell. While only trained on eight whale species, the diverse vocal ranges included in the model provide a strong foundation for future classifications and studies.
Tracking Bryde’s Whales
With the new insights gained from this research, scientists can now track Bryde’s whale vocalizations in relation to their geographical location and migration patterns, enhancing our understanding of the whales’ movements between breeding and feeding grounds. Allen noted a spike in detected vocalizations during the strong El Niño events of 2015 and 2016, hinting that climate changes may affect the whales’ migratory behavior.
Implications for Future Research
As climate change continues to impact marine environments, the identification of the biotwang will allow for refined monitoring of Bryde’s whale populations throughout the year. The research represents a significant step towards appreciating the complexities of marine life and emphasizes the potential of technology in conservation efforts.
This article provides a detailed exploration of the fascinating identification of the biotwang call from Bryde’s whales, emphasizing important developments in marine acoustics research and the potential implications for wildlife monitoring in the face of climate change.