
Everyone else seems to know the song except you.
People who sing karaoke know the feeling. Apparently birds too, and it’s a big problem for a bird species in Australia.
As the endangered regent honeyeater population declined over the years, some young birds were unable to find older birds to teach them to sing, a new study reports. As a result, the birds have not learned the songs they need for advertising and other evolutionary business.
They try to compensate for this by imitating songs from other species of birds. But because female honey-eaters cannot easily be moved by unfamiliar melodies, the courtship ritual is doomed to failure.
“We find that when some men are not paired, they spend all day singing looking for a partner,” said Ross Crates, the newspaper’s lead author and postdoctoral fellow at the Australian National University in Canberra.
A failed tryst or two would not be a reproductive problem for a healthy population. In a species estimated to have 200 to 400 members that span an area in southeast Australia larger than the UK, the loss of song culture may be what researchers have termed “precursors to extinction.”
The study was published in the journal Proceedings of the Royal Society B on Wednesday. She analyzed the sightings of wild regent honey eaters from July 2015 to December 2019 and their field records from the 1980s to the present day.
The researchers found that 12 percent of the male regent honey eaters in the study did not learn specific songs for their own species. Deviating from the “regional cultural norm” was associated with reduced reproductive success, and learning to sing the tunes of other birds did not help.
“It’s exquisite work that tells a terrible story,” said David Watson, an ecology professor at Charles Sturt University in Australia who was not involved in the research, of the new study.
“They are carefully conducted scientific, reasonable and evidence-based conclusions that describe in a few short pages what extinction of a species sounds like,” Professor Watson said in an email. “It doesn’t happen with a bang, but with a slow whimper.”
The results underscore the importance of including animal cultural diversity in conservation studies, said Kristina Paxton, a postdoctoral fellow at the University of Hawaii at Hilo who studied the songs of Hawaiian forest birds and was not involved in Australian research.
“This study contributes to a growing understanding that for many animals, such as humans, the loss of cultural identity can have profound effects on their ability to survive,” she added.
Regent Honeyeaters are a social species that once roamed in large herds, feeding on flowering eucalyptus and mistletoe trees in an area in Australia from roughly Melbourne to Brisbane. Not only do they sing to mate with each other, but also to mark the territory and give advice on where to find food.
When temperate forests were cleared across Australia over the past few decades, the population declined – from about 1,500 birds in the late 1980s to about a fifth that much more than two decades later, according to government data. The species also started losing turf fights with competitors like the noisy miner, another honey eater known for its aggressive behavior.
A century ago, “there were plenty of regent honey-eaters who could withstand the noisy miners,” said Mick Roderick, program manager at Birdlife Australia. “But now, because there is literally only one pair here and one pair here – they are so rare – they just sit ducks.”
A male regent honeyeater usually makes a “warbly noise” similar to that of a small turkey and claps its beak as he sings, said Mr. Crates. But when young men can’t find mentors to learn from, they try instead to mimic the songs of other types, including one that sounds “metallic” and one that resembles a repetitive whistle.
Mr Crates said a useful human analogy would be the indigenous societies in Australia and the United States, whose languages have been lost after the populations became too thin to sustain.
“It’s nice to be able to speak two languages,” he said, “but when it’s at the expense of your mother tongue and you can’t connect with your friends and family – or with someone you might want to meet – it has its price. “