Ocean melodies: Scientists solve puzzles about whale song

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Humpback whale: "You can't just decide to sing higher, for example"

Photo: OceanPhoto / imago images

They sing to communicate with their fellow whales or to woo females: the song of whales fascinates more than just scientists.

A team of researchers from universities in Odense, Rochester and Vienna has now managed to solve a mystery about whale song.

According to this, humpback whales and other baleen whales have developed a special “larynx” that allows them to communicate underwater.

"Our data clearly shows that the mystical larynx has retained its key role as a vocal organ," says the study.

The astonishing thing is that despite numerous anatomical specializations, the larynx of baleen whales functions according to the same principle as the larynx in humans and most other land mammals.

The study also provides an explanation for why the noise we make in the ocean is so disruptive to ocean giants.

The song of the whales is limited to a narrow frequency that overlaps with the noise of the ships.

“Sound is absolutely crucial for the survival of whales,” said study leader Prof. Coen Elemans to the BBC.

"Because that's the only way they can find each other to mate in the ocean."

To unravel the mystery of whale song, Elemans and his colleagues conducted experiments using larynxes that had been carefully removed from three carcasses of stranded whales.

These were a minke whale, a humpback whale and a sei whale.

They then blew air through the massive structures to create the sound.

Unlike humans, baleen whales have a large U-shaped structure with a fat pad at the top of the larynx.

This anatomical peculiarity allows the animals to sing by recycling air.

At the same time, water is prevented from being inhaled.

The researchers created computer models of the sounds and were able to show that the song of baleen whales is limited to a narrow frequency that overlaps with the noise of ships.

"For example, you can't just decide to sing higher to avoid the noise we make in the sea," says Elemans.

The study once again shows how man-made ocean noise prevents whales from communicating over long distances.

This knowledge could be crucial to protecting humpback whales, blue whales and other endangered ocean giants.

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