Wild regent honeyeater's song (audio supplied).
Scientists from The Australian National University (ANU) and the Taronga Conservation Society Australia have successfully restored the lost traditional song of one of Australia's most endangered birds, offering new hope for the survival of the critically endangered regent honeyeater.
The new study reveals how targeted "song tutoring" at Taronga Zoo in Sydney and Taronga Western Plains Zoo in Dubbo has revived a disappearing cultural trait vital to the species' survival.
Birdsong plays a vital role in mate attraction, territory establishment and social cohesion. Like human language, many bird species learn their songs from experienced 'tutors'.
Without access to these tutors, young birds can develop incorrect or simplified songs - with serious consequences for breeding success.
With fewer than 250 individuals remaining in the wild, the regent honeyeater has faced not only population decline but also cultural erosion.
"Everything we know about the function of birdsong suggests that having a cohesive dialect will be critical to the success of the reintroduction program and the survival of the species," lead author Dr Daniel Appleby said.
Previous research showed that young wild birds, unable to find older males of their own species, were mistakenly learning the songs of other birds.
At the same time, zoo-bred regent honeyeaters were singing songs that differed from all known wild variants - potentially reducing their chances of successfully integrating and breeding in the wild after release.
In response, researchers launched a series of innovative song tutoring experiments within Taronga's conservation breeding program.
Using recordings and direct exposure to just two wild-born male tutors, scientists taught young zoo-bred males the species' traditional wild song - a song that has now been lost from the wild populations and was becoming increasingly simplified as numbers declined.
The results were striking. In subsequent years, zoo-bred males that had learned the traditional song went on to tutor the next generation.
"After a year of negative results, we could not believe our ears when some small tweaks to our tutoring approach led to the juveniles singing like wild birds," Dr Ross Crates said.
Today, more than 50 per cent of zoo-bred males sing songs that closely resemble the historic wild song.
Remarkably, the zoo population is now the only remaining source of the traditional regent honeyeater song.
By releasing these birds into the wild, researchers hope the culturally restored males will pass on the traditional song to wild birds, helping to stabilise and even rebuild song culture in the natural population.
"Hearing the zoo-bred birds sing their wild song for the first time was incredibly moving - like a piece of their identity coming back to life," Dr Joy Tripovich said.
"Restoring this precious song gives real hope for the species' future."
This cultural rescue could significantly improve breeding success and overall fitness of zoo-bred birds - a critical step toward preventing extinction of the regent honeyeater.
"We are extremely grateful to the two wild males recruited to the zoo population. Without them, the traditional wild song would have been lost forever," Dr Crates said.
The study highlights the growing recognition that the conservation of biodiversity must also include conserving animal culture.
By integrating behavioural science into conservation programs, researchers demonstrate that protecting species means protecting not only their genes, but also their learned traditions.
"Our work teaching regent honeyeaters to sing wild type songs has far reaching implications for captive breeding and reintroductions," Dr Appleby said.
As global biodiversity continues to decline, the findings provide a powerful example of how innovative, culture-aware conservation strategies can deliver tangible outcomes for species on the brink.
The study is published in Nature Scientific Reports .
