The chirping of birds echoed through a packed lecture hall in Hong Kong, though there wasn't a feather in sight.
Residents, some pressing the sides of their throats or contorting their bodies, imitated the rhythmic calls of the koel, brown fish owl and Asian barred owlet.
One donned elaborate headgear to mimic the yellow-crested cockatoo - a bird that is among the world's most endangered species. About a tenth of the 1,200 to 2,000 left call the financial hub's concrete canyons home.
Bob Chan, who took top prize at the Hong Kong Bird Watching Society's first-ever birdcall contest on Saturday, chose the tiny Eurasian Tree Sparrow, another longtime urban dweller.
"I saw other contestants giving their all ... and imitating very well," he said admiringly of his nearly 100 fellow participants, each judged on their rhythm and tone.
One judge, Hong Kong-based ecologist and ornithologist Paul Leader, told AFP he was thrilled the competition had gotten people like Chan thinking about the birds they share the city with.
"If people don't care about birds, how are you going to get them to protect them and conserve them?" he said.
"I'm just happy to see people who have a genuine interest in birds and wildlife. That's a great start," he said of the event aimed at raising ecological awareness.
Despite its relatively small size, more than 580 types of birds -- about a third of China's total species -- have been recorded in Hong Kong.
That diversity is attributed to Hong Kong's status as a vital stopover on the East Asian-Australasian Flyway for migratory birds, thanks to the city's varied habitats -- from wetlands and forests to shrublands and coastal areas.
In recent years, a mega-development plan in Hong Kong's north has raised concerns among environmentalists about the reduction of the wetlands.
The government has said fears over the project's environmental impact are overblown.
But Tom Li, assistant research manager of the Hong Kong Bird Watching Society, told AFP the wetlands were a "critical issue" for birds in the city.
"Whether habitats like wetlands can be preserved over the next 10 to 20 years without being squeezed by large-scale urbanisation development" will be key to maintaining biodiversity, he said.
