In a recently published research article in the journal Frontiers in Marine Science, Saskia Cathrin Tyark reveals new, sensational findings about the humpback whale’s song. The study is based on sound recordings from the Lofoten-Vesterålen marine observatory, and shows that the area is an important stopping point on the humpback whales’ migration route. The researchers behind the study are associated with the Institute of Marine Research, UiT, the Norwegian Polar Institute and Lund University in Sweden. After a whole year, the researchers were left with recordings from 189 days of recordings. Now 79 days of whale song have been analysed. And what they found after hundreds of hours of listening, surprised them greatly. Not only do humpback whale songs change from month to month and year to year. – The songs also have a cultural feature. The whales learn from each other through imitation, says Saskia Tyarks, who is the lead researcher behind the findings. Researcher Saskia Tyarks has spent more than 100 hours listening to whale songs. – I never get tired of listening, she says. Photo: Private – Unearthly beauty With its 30-40 tonnes, the humpback whale is a heavyweight. But it is also known for its special singing voice. The complex and melancholic howl can go on for hours and can be heard for a three mile radius. “WHALE”: – Whale song is both beautiful and fun to listen to. Almost otherworldly, says researcher Saskia Tyarks. The humpback whale is the only animal in the ocean to have sold multiple times platinum with a music album, which also inspired the “Save The Whales” campaign in the 1970s. Saskia Tyarks has listened to whale song for more than 100 hours. She has stopped counting. She never gets bored. – Whale song is both beautiful and fun to listen to. Almost otherworldly. I never get tired of listening, says the passionate researcher. Getting more complicated Until now, sound recordings of singing humpback whales have been made at southern latitudes. It has long been an established truth that humpback whales only sing while they are outside Africa or the Caribbean, where they mate and give birth to their young. No other mammal travels as far each year as the humpback whale. The map shows the migration routes of the humpback whales that winter along the coast of northern Norway and Svalbard. Graphics: Audun Rikardsen / UiT Norway’s Arctic University Until last year, when researchers started analyzing the humpback whale sounds from the hydrophones of the ocean observatory in the depths off Lofoten and Vesterålen. In late autumn, the humpback whales return to northern Norway to hunt for herring. Saskia Tyarks says that the whale song then consists of simple, monotonous sounds. As they encounter other whales, the song becomes more complicated. While some whales sang short sessions of 13 minutes, others sang for over 13 hours straight. Humpback whale migration Humpback whales are found in all the world’s oceans, and make the longest migrations of any mammal in the world. The distances can be as much as 8,000 km. The migrations are most often between feeding areas in more arctic regions and mating and feeding areas in the tropics. In the North Atlantic, humpback whales often feed in summer and autumn, and are found in areas as far north as Svalbard. In late winter, the whales go to the Caribbean or West Africa to mate or give birth. In recent years, the whales have made a stop in the fjords outside Troms on their way south. Size: Up to 15 meters and 30 tonnes Lifespan: Presumably the maximum age is at least 80 years Habitat: All world oceans. In our waters it occurs in the Norwegian Sea and the Barents Sea. Food: Fish and krill Distinctive features: Humpback whales have large, eye-catching protuberances which in the Atlantic are usually white – “megaptera” means “big wings”. Source: UiT/Havforskningsinstituttet – That the song becomes more complex may mean that the different stocks communicate, exchange and learn songs from each other. This in turn may indicate a higher cognitive capacity than we have so far thought, says Tyarks. When the grazing season is over, the researchers believe that the whales’ learning capacity is full, and that they have reached the ceiling of how much they can learn. In the North-East Atlantic, there are around 600,000 whales, according to the researchers’ new calculations. 10,000 of these are humpback whales. Photo: Kenneth Pettersen Then it’s on again after calving and mating. – Whether this is really the case, we can only speculate. For the time being, it remains a mystery, says Saskia Tyarks, who has had two research articles published about the humpback whales off Nordland. But what are they singing about? It is impressive, says ocean researcher Geir Pedersen at the Norwegian Institute of Marine Research, who is also participating in the study. – The recent study is based on data from the LoVe marine observatory, and shows that the area outside Lofoten-Vesterålen is an important stopping point on the humpback whales’ migration route. We probably wouldn’t have found this out either without the ocean observatory. Photo: Christine Fagerbakke / HI – It is surprising that a master’s student manages to get two articles out of his master’s thesis. That says something about how interesting and exciting these findings are. In the North-East Atlantic, there are around 600,000 whales, according to the researchers’ new calculations. 10,000 of these are humpback whales. Pedersen believes that the discoveries outside Nordland will help us understand the humpback whale better. Now the researchers will try to find out more about the mysterious whale song. Among other things, the sound recordings from Lofoten and Vesterålen will be compared with similar studies of pods of whales from Iceland and other sides of the Atlantic. In this way, the researchers hope to find out whether there is an exchange also across the geographical areas. But what are they singing about? There could be several reasons for that, according to Pedersen. Only the male whales sing. The song has therefore been interpreted as a way of attracting females. Now the researchers know a little more. Photo: Kenneth Pettersen The fact that they have to start over when they come north may be about the external environment they find themselves in. – Or that they have to use their energies for something more sensible than singing. Or simply that they are unable to learn more. These are open questions that we want to find out, says ocean researcher Geir Pedersen. Tyark’s dream scenario is to be able to tag some of the whales in order to record their singing and behavior when they are in the Caribbean. – Another approach is to combine a visual and auditory approach to see what the whales do when they sing. With an underwater drone and hydrophone. As far as I know, this has never been done in Norwegian waters and can perhaps give us a bit more insight into why the whales sing up here. Although the whale song may remain a mystery, more is now known about the humpback whales that wander along the Norwegian coast, says Saskia Tyarks. Because these whales live with many disturbances during this period. – There is a high level of activity by vessels, especially whale watching boats during the winter months. The knowledge will help us to determine the importance of this area in the North Atlantic. Greater awareness of the humpback whale’s behavior will also contribute to better management.
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Whale song from Lofoten and Vesterålen surprised scientists – news Nordland
