In the centre of Kathmandu, Gautam Sapkota raises his hand to his mouth and emits a series of loud screeches. Within minutes, the sky above him is full of hundreds of crows answering his call.
Sapkota can mimic the calls of 150 birds, and in 2008 was named a "young conservationist of the year" by the World Wildlife Fund (WWF) for his ability to entertain and educate young people about nature.
"Right now I am saying in crow 'Come, I am your friend'," said the 26-year-old, as the noisy black birds wheeled overhead and settled in nearby trees.
At the regular presentations he makes to schools, Sapkota astounds crowds with his bird calls, and encourages children to learn about wild animals and the importance of protecting the environment.
"He has a unique way of generating interest about birds and teaching students about conservation," WWF communication officer Sanijb Chaudhary told AFP.
Crows were one of the first birds Sapkota successfully imitated and, after years of practice, he is able to call them to him – and make them fly away.
On a recent afternoon in the grounds of Nepal's parliament he impressed local workers with his abilities.
"It's amazing, and hard to believe it's real," said building supervisor Narendra Chaudhary as he watched a huge flock of birds circle above Sapkota.
But learning his skills during Nepal's recent civil war came at a risk for Sapkota, the eldest son of a farmer.
BIRDS ARE INDICATORS OF A HEALTHY ECO-SYSTEM
In 2005, as the army battled the former rebel Maoists who now run the country, Sapkota was in the jungle near his home in central Nepal learning bird calls when he was picked up by an army patrol.
They accused him of being a Maoist spy.
"It was only after I mimicked the sound of about 12 birds they realised I was genuine and let me go," said Sapkota, who prior to his calling as a bird mimic worked in a factory making noodle packets.
With diverse habitats that range from the world's highest mountains in the north to tropical plains and jungles in the south, Nepal is a paradise for bird lovers, with around 850 species recorded.
Of those, 31 are classified as "globally threatened" by the International Union for Conservation of Nature, said Bipendra Joshi, executive officer from the Bird Conservation Nepal group.
"Four species became extinct between 2001 and 2007," he said.
In addition, "fish-eating birds and migratory birds are declining in numbers in Nepal's wetlands due to over-fishing by locals and habitat encroachment," he said.
"Birds are indicators of a healthy eco-system, but many species are under threat. Both poaching and habitat destruction are on the rise.
"Poaching of tiger and rhino gets a lot of attention, but the same is not true of birds.
"Sapkota can help raise interest in the plight of Nepal's birdlife."
Sapkota wants to develop his work in schools, and also release an album of popular folk tunes done in bird calls.
"People laugh when I make these sounds and I enjoy it, but at the same time I am also sharing my knowledge about birds and the eco-systems they live in," he said.
"Rarer species here may become extinct, but I am glad that I am able to preserve the voices."