European researchers have been “surprised” by an Australian duck which learned to swear.
The musk duck named Ripper was the subject of a 1987 study by researcher Dr Peter Fullagar, but the bird’s ability to vocalise had gone largely unknown by the international scientific community.
Thirty-five years on, Netherlands-based Professor Carel ten Cate came across a short note about the duck’s behaviour in an Australian reference book.
“At first, when I read about the story, I thought, okay, it's a hoax,” he told Yahoo News Australia last night.
“Therefore I was very keen to trace the original recordings.”
Luckily audio of the duck had been donated to an archive and Professor ten Cate was able to verify Ripper’s behaviour first-hand.
What he heard left him stunned, the hand-reared duck was likely imitating the sound of his keepers at the sanctuary near Canberra where he was kept.
Ripper was clearly saying the phrase “you bloody fool”.
Other vocalisations produced by the duck included the imitation of a wire door closing and a whistle.
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While vocal learning is known to occur in songbirds, parrots and hummingbirds, this was the first time Professor ten Cate knew of it occurring in a duck.
These groups of birds likely inherited the ability to mimic from a common ancestor, however ducks branched off and developed separately before this behaviour occurred, making this a new incidence of independent evolution.
“It’s a rare event, and therefore a rare discovery,” Professor ten Cate said.
“In several ways, it's quite an extraordinary species.”
Vocalisation has not been observed in any other duck species, and it is only known to occur in male musk ducks as part of their sexual display.
Professor ten Cate now hopes to better understand the taxonomic status of the species and whether there are any comparable behaviours in closely related birds.
The research by Dr Peter Fullagar and Professor ten Cate has now been published by The Royal Society.
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