Flocks of birds among major beneficiaries of environmental cleanup

In spite of its plain appearance, intelligent monitoring equipment on the lake island of the Grand Canal Forest Park in Beijing's Tongzhou district can recognize bird species via their calls.

The equipment, namely a white pole with solar panels, audio and visual sensors and an antenna, has recorded 165 bird species and accumulated 137,000 pieces of birdsong since its installation in March.

Hu Yan, director of the city's wildlife rescue center, said birds are one of the least likely animal groups to be observed and recorded accurately. It is impossible to have all-weather, long-term continuous statistics if the survey relies on human observation alone.

Moreover, many birds have camouflage and are hard to be detected — even with infrared cameras.

The smart equipment, developed by the Institute of Zoology at the Chinese Academy of Sciences, can recognize the sounds of more than 800 bird species, with an accuracy rate of more than 80 percent for common species.

Birdsong not included in the database is stored in a separate electronic folder. Experts will help identify and confirm the specific category of the sound.

Based on the monitoring results, Hu said human activities in specific areas should be adjusted at specific periods to reduce the disturbance to birds.

Nearly 50 intelligent sets of birdsong monitoring equipment have been installed across the city, which have accumulated a total of more than 3 million pieces of audio data. They are distributed in places such as Wenyu River Park, Bulaotun township, Wuling Mountain, Shisanling Reservoir, Cuihu Lake and Yongding River.

Since 2020, Beijing has carried out a biodiversity survey annually. The results showed that the Chinese capital has become one of the most biodiverse metropolises in the world, with progress made in the construction of ecological civilization.

In 2020-22, Beijing recorded 6,408 species, including 399 vertebrates, 2,396 insects and 884 large fungi.

Compared with a decade ago, the city has added nearly 100 bird species. In May, the critically endangered yellow-breasted bunting was spotted in Olympic Forest Park. The bird species is also under first-class national protection in China. The discovery of the rare bird in a city park indicates that the ecological environment of the Chinese capital has been greatly improved, according to the wildlife rescue center.

Beijing now has more than 2,000 species of vascular plants, including 15 species under top-level State protection. Some plants that were rarely found in the city in the past have also been discovered in recent years.

Natural shorelines are an indispensable part in the living environment of small animals. Wenyu River Park, located at the junction of Chaoyang, Shunyi and Changping districts, is a leading example of protecting and restoring natural shorelines.

A small island on the north side of the park's Qinhu Lake is a paradise for small animals. For some birds such as sparrows, magpies and crows, it is a place to drink and bathe in summer, and a supply and transit station in winter.

In 2022, the average natural shoreline retention rate reached 69.5 percent in Beijing. The figure stood at more than 75 percent in some key rivers like Yongding, Chaobai and Wenyu.