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Humpback whales’ sign of loneliness

Aussie scientists have noticed fewer humpback whales are wailing as their population grows, suggesting they wail most when lonely

Australia outlawed commercial whaling in our oceans around 45 years ago. Picture: the Cetacean Ecology Group, University of Queensland
Australia outlawed commercial whaling in our oceans around 45 years ago. Picture: the Cetacean Ecology Group, University of Queensland

READING LEVEL: GREEN

Those melancholy* tunes sung by humpback whales may really be a sign of loneliness.

Scientists who tracked humpback whales in Australia noticed that fewer whales wailed* to find mates as their population grew.

“Humpback whale song is loud and travels far in the ocean,” said marine biologist Rebecca Dunlop, who has studied humpback whales that breed near the Great Barrier Reef for more than two decades.

As whale numbers grew following the end of commercial whaling* — one of the world’s great conservation* success stories — she noticed something unexpected.

“It was getting more difficult to actually find singers,” said Ms Dunlop, who is based at the University of Queensland in Brisbane. “When there were fewer of them, there was a lot of singing — now that there are lots of them, no need to be singing so much.”

Scientists first began to hear and study the elaborate* songs of humpback whales in the 1970s, thanks to new underwater microphones. Only male whales sing, and the tunes are thought to play a role in attracting mates.

A surface-active adult humpback whale migrating along the eastern coastline of Australia. Picture: the Cetacean Ecology Group, University of Queensland
A surface-active adult humpback whale migrating along the eastern coastline of Australia. Picture: the Cetacean Ecology Group, University of Queensland

Eastern Australia’s humpback whales were facing extinction* in Australia the 1960s, with only around 200 whales left. But numbers grew and reached 27,000 whales by 2015.

As whale numbers increased, their courtship* changed. While two in 10 males were singers in 2004, a decade later that ratio had dropped to just one in 10.

Ms Dunlop speculates* that singing played a big role in attracting mates when populations were severely depleted*.

“It was hard just to find other whales in the area, because there weren’t many,” she said.

When whales live in bigger populations, a male looking for a mate also has to ward off the competition, and singing may tip off other suitors*,” she explained.

Though migrating, these humpback whales are still undertaking breeding behaviours such as joining with, and competing over, available females. Picture: the Cetacean Ecology Group, University of Queensland
Though migrating, these humpback whales are still undertaking breeding behaviours such as joining with, and competing over, available females. Picture: the Cetacean Ecology Group, University of Queensland

To be sure, the seas are still noisy. Many humpbacks woo with a combination of singing and physical jostling*, the Australia researchers report.

“Such a big increase in animals over the time they were studying gave them a unique opportunity to get insights about changes in behaviour,” said Simon Ingram, a University of Plymouth marine biologist in England, who not involved in the study.

Mr Ingram said that while humpback whales must have been singers long before whaling depleted their numbers, the new study highlights just how essential* their beautiful songs were to their survival and recovery.

“Clearly singing became incredibly valuable when their numbers were very low,” he said.

GLOSSARY

  • melancholy: a feeling of sadness
  • wailed: to make a long, high-pitched sound
  • commercial whaling: the purpose of hunting and killing whalers to sell their meat
  • conservation: the protection of earth’s natural resources
  • elaborate: work carried out with great care and attention to detail
  • extinction: the act of making something extinct, or no longer existing
  • courtship: the process of seeking a partner
  • speculates: to make guesses or wonder about something
  • depleted: to lessen dramatically
  • suitor: someone who you seek to date
  • jostling: to push or bump on purpose
  • essential: extremely important

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QUICK QUIZ

  1. Why do humpback whales wail?
  2. What happened after commercial whaling stopped?
  3. What was the ratio of “male singers” in 2004?
  4. When did scientist first start studying the songs of humpback whales?
  5. Aside from wailing, what else do humpback whales do to attract a mate?

LISTEN TO THIS STORY

CLASSROOM ACTIVITIES
1. Write the words
Write the words for a song that you think a lonely whale would sing. Use the information in the story to help get ideas.

Time: allow 25 minutes to complete this activity
Curriculum Links: English, Critical and Creative Thinking, Music

2. Extension
What evidence have the scientists used to make their findings about whale song? Write down what they think, or their conclusions, and the evidence, or information, that backs up their ideas.

Time: allow 25 minutes to complete this activity
Curriculum Links: English, Science

VCOP ACTIVITY
To sum it up
After reading the article, use your comprehension skills to summarise in a maximum of three sentences what the article is about.

Think about:

  • What is the main topic or idea?
  • What is an important or interesting fact?
  • Who was involved (people or places)?

Use your VCOP skills to re-read your summary to make sure it is clear, specific and well punctuated.