It's truly hard to find anything in common between a 58-year-old retired businessman enjoying his retired life in Beijing, and a young college student studying biology at a university in Changsha, Hunan province.

However, they have teamed up twice already this year and competed together in a special kind of race — a bird race.

Bird races are events where participants "race" to identify bird species within and specific area and timeframe. The participant or team that identifies the most species is declared the winner.

Zhao Meisheng has been observing and photographing birds in his spare time for over two decades. However, it was only after his retirement a few years ago that he began to take this hobby more seriously.

"Previously, I focused mainly on bird photography, but now I dedicate more time to bird-watching," he said.

Zhao has started using a smartphone-based recording tool to document and manage his bird sightings. He actively participates in bird surveys as a volunteer and joins bird races held across the country.