Some of the most elusive sounds in nature — echidnas talking to each other — have been recorded for the first time.
Researchers believe it is likely that they are the sounds of echidnas flirting, as the spiky creatures only seem to vocalise during breeding season.
In what is believed to be a scientific first, researchers from Curtin University have obtained recordings of short-beaked echidnas producing a range of sounds including cooing, grunting, and wheezing.
“It means we better understand how echidnas behave and interact with each other,” said Christine Cooper, who has been studying the animals at Dryandra National Park near Narrogin, Western Australia.
“We were really pleased because the first time we heard it, we didn’t have any mechanism with us to record it and we were like, ‘Oh, that’s really unusual’,” Dr Cooper said.
“The next time when we were actually able to record it, we were really pleased.”
One question answered, more raised
Vocalising seems to be very rare behaviour for echidnas.
Dr Cooper said in the 20 years she had spent studying the monotremes, she had only heard them vocalise five times.
While it was suspected the creatures made noises, there had never been solid proof before.
To record the sounds, the research team used hand-held microphones, as well as a camera and microphone that was left outside the entrance of a cave frequently visited by echidnas.
Now that researchers know echidnas do vocalise, the next step is trying to figure out what they are saying.
“What do these calls mean? What context are they used in?” Dr Cooper said.
“We have only heard them from adult animals during the breeding season, suggesting echidnas only find their voice when reproductively active.”
An ancient trait
The discovery is also important for our understanding of how wildlife evolved on our continent.
Echidnas are monotremes — mammals that lay eggs — like platypuses, which are also known to vocalise.
With echidnas able to communicate through sound just like other mammals, it suggests this trait must have been developed in a common ancestor.
“Our findings confirm that acoustic communication using sound likely developed 100 to 200 million years ago, and before monotremes diverged from other mammals,” Dr Cooper said.
If any echidna enthusiasts are able to record sounds of the animals communicating, Dr Cooper said she would be eager to hear them.
“It would be lovely to hear it because it certainly happens quite rarely,” she said.
