HUMPBACK WHALES SONGS AND WHY WE ARE RECORDING THEM HERE IN THE WHITSUNDAYS

We have been recording humpback whale songs in the Whitsundays during the past two whale seasons. The songs are submitted to the University of Queensland, Centre for Marine Science, where Professor Michael Noad is the Director and Genevieve Williams is doing a PhD studying the social learning of whales.

Michael has been researching the evolution and function of humpback whale song, focusing on how the whales themselves use sound to communicate.

The songs of these whales is one of the most complex acoustic displays of any animal known. Social sounds are made by all whales. However, it is only male humpback whales that sing songs. The songs are structured.

There are seven individual populations of humpback whales in the southern hemisphere. The Australian East Coast humpback whales are a single population. Amazingly all males in one population sing the same song. It is possible to tell where a humpback is from by its song. They learn the exact sounds, without simplifying or leaving anything out. Their songs are constantly slowly evolving, with small sections changing each year. All males listen to the song the others are singing, and incorporate the evolution of the song into their own song; which is social learning.

Song data is collected from Point Lookout on Stradbroke Island and the Sunshine Coast. On the northerly migration the songs are not fully aligned, but by the time they pass Stradbroke Island again on their return migration, the song is very much together and the same. That’s why UQ researchers are extremely interested in hearing what their song is like in the Whitsundays.

Professor Michael Noad, has also discovered that the southern hemisphere population have song ‘Revolutions’ as well as just ‘Evolution’. A ‘revolution’ is a very rapid change in the song.

In the early 2000s in 18 months there was a total new song.

But even more interesting, they discovered it was the same song that the Australian West Coast population of humpbacks was singing the year prior. Since then, they have discovered the song moves by individual populations in an easterly direction all across the South Pacific.

Dr Allan Garland has discovered a song which moved from the Australian West Coast to French Polynesia. Recently it’s been discovered it has moved as far as Ecuador. It means humpback whales can learn an entire song pattern from another population very quickly, even if it’s complex or difficult.

The findings support the idea that songs are being learned by whales on shared migration routes or shared feeding grounds like Antarctica. In the northern hemisphere, each separate population has their own songs, but they don’t pass it along like the southern hemisphere populations, most likely because the northern hemisphere populations don’t share migration routes or feeding grounds. We have no idea why they change the song or why they pass it from population to population.

Humpback whale vocalisation has an extensive repetiteur of sounds, including low frequency moans and grunts, and high frequency cry and whistles. So, what makes a song different to social noises?

• The basic level of a song is a ‘unit’ like a moan, grunt or belch.
• When individual units are sung in a set order, they are called a ‘phrase’, eg moan, moan, cry, cry.
• When a phrase is repeated several times, it’s called a ‘theme’.
• Multiple themes are sung in a set order, called a ‘song’.
• Songs are sung over and over multiple times from 5 minutes to over 30 minutes.

To listen to a whale song recorded in the Whitsundays join the WHALES OF THE WHITSUNDAYS Facebook page and turn up the volume.

Contributed with thanks to Kellie Leonard - Whales of the Whitsundays.

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Genevieve Williams explaining a whale song recording

Movement of the whale song along the southern hemisphere populations provided by UQ Centre for Marine Science

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