A great egret forages at a wetland in Ledong County, south China's Hainan province, Jan 17, 2021. (PU XIAOXU / XINHUA)

HAIKOU - After driving nearly 800 km over three days, 35-year-old Cheng Cheng, who had tirelessly trenched in the swamp for hours, finally found a perfect spot to observe an endangered waterbird.

Hundreds of thousands of migratory birds spend winter in Hainan every year as it is located along their migration route from East Asia to Australia

Cheng is not only a passionate lover of nature but an expert on wetlands and waterbirds, as well as the founder of the Hainan Bird-Watching Society, a bird-watching organization in south China's Hainan province since 2015.

In just two hours, Cheng's team had spotted and recorded over 1,800 birds of different kinds during this year's annual bird-watching survey from Jan 15 to 17 across the island province rich in aquatic habitats.

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Birders observe migratory waterbirds in Wenchang, south China's Hainan province, Jan 15, 2021. (PU XIAOXU / XINHUA)

Hundreds of thousands of migratory birds spend winter in Hainan every year as it is located along their migration route from East Asia to Australia.

The team, consisting of over 50 experts, enthusiasts and volunteers, had to stand barefoot in the swamp under the scorching sun for hours at a time to collect as much information as possible on the different species of migratory birds, Cheng said.

"However, it is worthwhile doing whatever we can to protect the birds during their long and risky migration," she added.

The most rewarding experience of the trip was spotting seven black-faced spoonbills in Ledong Li Autonomous County, said Li Fei, an expert of the team, who observed the endangered species through his monocular telescope that can magnify images up to 30 times.

Birders study migratory waterbirds at Yingge Sea Salt Field in Ledong County, south China's Hainan province, Jan. 17, 2021. (PU XIAOXU / XINHUA)

His teammates soon crowded around him, cheering out, and by recognizing the red label on the bird's leg that read "Y66," they confirmed the identity of the long-legged wading bird through a quick online search: a young bird born last summer in the Republic of Korea.

"This was the first time that it had been spotted in China," Li recalled.

He later uploaded the record to a website that allows observers such as Li to share their latest findings on birds to help complete the picture of their migration routes and information on their health conditions.

"Birds are sensitive to the natural environment and their well-being can reflect the environmental conditions," said Cheng.

Whiskered terns are seen at a wetland in Wanning, south China's Hainan province, Jan 16, 2021. (PU XIAOXU / XINHUA)

The data of the survey will also provide crucial references for local governments and research institutes to protect the birds and improve the environment, Cheng added.

In addition, more and more local people are joining in the efforts as their awareness of environmental protection grows. "Several years ago, less than a dozen would volunteer for our annual survey, but the number has risen to dozens in recent years, including some from outside Hainan," she said.

Apart from the Hainan Bird-Watching Society, another six investigation teams also participated in an extensive survey that Hainan launches every year across its 50 waterfowl habitats.

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A birder takes photos of black-faced spoonbills at a wetland in Dongfang, south China's Hainan province, Jan. 18, 2021. (PU XIAOXU / XINHUA)

"We hope people around the world can unite to observe and protect waterbirds, ensuring there will be no more hunting by humans," Cheng said.

Since the survey, Cheng has begun a tight schedule training volunteers, conducting research, and promoting the importance of protecting birds to more people.

Cheng believes that protecting wildlife should not only be left to experts, and she hopes well-trained volunteers will become the backbone of the survey and protection efforts someday.

Birders study migratory waterbirds in Wanning, south China's Hainan province, Jan 16, 2021. (PU XIAOXU / XINHUA)