A pigeon sits atop a cage during a merbok (zebra dove) singing competition at the Kebun Baru Birdsinging Club in Singapore June 23, 2019. Picture taken June 23, 2019. Just after dawn in Singapore, about 150 black-and-white striped zebra doves were hoisted in their cages on to tall poles in a large field for a singing competition. REUTERS/Edgar Su

A bird owner hangs up his cage before a merbok (zebra dove) singing competition at the Kebun Baru Birdsinging Club in Singapore June 23, 2019. Picture taken June 23, 2019. The contest, popular among retirees in the ageing city-state and Southeast Asian countries such as Thailand, is fiercely competitive and top performers can be worth thousands of dollars. But the prizes are more about trophies and bragging rights. REUTERS/Edgar Su

A judge listens to merboks (zebra doves) sing during a competition at the Kebun Baru Birdsinging Club in Singapore June 23, 2019. Picture taken June 23, 2019. Jason Tan, 66, a Singapore resident born in Thailand who has won the competition dozens of times, said he finds the cooing of the birds, domestically known as 'merbok', relaxing. REUTERS/Edgar Su

A bird owner prepares to hang his cage during a merbok (zebra dove) singing competition at the Kebun Baru Birdsinging Club in Singapore June 23, 2019. Picture taken June 23, 2019. Sunday's competition, which lasted four hours in the middle of a nondescript housing block in a central Singapore neighbourhood, is one of several held each year. REUTERS/Edgar Su

Participants and bird owners wait for the start of the merbok (zebra dove) bird singing competition at the Kebun Baru Birdsinging Club in Singapore June 23, 2019. Picture taken June 23, 2019. The doves are divided into three categories depending on the pitch of their songs, and three judges decide the winners. REUTERS/Edgar Su

A man looks at trophies as a judge listens to merboks (zebra doves) sing during a competition at the Kebun Baru Birdsinging Club in Singapore June 23, 2019. Jerry Lye, a Malaysian who has been judging birdsong since the '90s, said the best songs feature a crescendo. "You have to listen out for the birdsong that has more texture, that is sweeter, that has a long ending, the middle has to be short, and slow...If it's like that, then they will be at the top, so that is considered a good bird." Tan, whose bird finished third, left a little disappointed but optimistic for the dove's singing career. REUTERS/Edgar Su