Bowhead Whales Borrow Songs from Other Arctic Species

In the waters around Svalbard, bowhead whales are revealing an unexpected dimension to their already remarkable vocal behavior. A new study shows that these Arctic giants do not rely solely on their own repertoire. They also imitate the sounds of other species and incorporate them into their songs.

Bowhead whales are known for producing some of the most complex and variable songs in the animal kingdom. Males sing primarily during the winter months, when breeding activity peaks. Unlike humpback whales, which tend to converge on shared songs, bowhead whales continuously change their vocal patterns, creating an extraordinary diversity that has long puzzled scientists.

Years of underwater acoustic recordings have now provided a clearer picture. Researchers from the Norwegian Polar Institute detected repeated cases where bowhead whale songs contained sounds closely matching the calls of bearded seals. These long, descending trills are a defining feature of the Arctic soundscape, and both species produce sounds within similar frequency ranges. Because their vocal activity overlaps outside peak breeding periods, whales are likely regularly exposed to these calls. The trills are also acoustically demanding, and incorporating them into whale songs may reflect a form of vocal performance.

At first, the recordings raised doubts. The sounds seemed out of place in whale songs. But detailed analysis confirmed that the whales themselves were producing them. Crucially, the imitated sounds were not isolated. They were embedded within the whales’ own structured and repetitive song patterns, showing that the whales were actively incorporating and modifying what they heard.

This behavior points to complex vocal learning, a rare trait in the animal kingdom. It involves the ability to acquire new sounds through listening and reproduce them with precision. While this ability is well documented in some birds and a few mammals, it is less commonly demonstrated in baleen whales. The findings place bowhead whales among the select species capable of such advanced acoustic flexibility.

Such vocal flexibility may play a role in reproduction. Bowhead whales are believed to rely on acoustic displays during courtship, where song complexity may signal individual fitness. In other species, more elaborate or demanding vocalizations are linked to mating success, and a similar mechanism may be at play here.

There are also indications that bowhead whales may imitate other sounds in their environment, including calls from narwhals and even ice-related noises. These cases are less certain, but they suggest that the whales may be responding to a broader and highly dynamic acoustic environment.

The Arctic Ocean is a complex and ever-changing soundscape, shaped by sea ice, seasonal shifts and overlapping animal calls. Within this environment, bowhead whales appear not only as prolific singers, but also as attentive listeners, capable of reshaping their songs in response to the sounds around them.

Léa Zinsli, PolarJournal