(CFP Photo)

The aquatic vegetation restoration project at Yangcheng Lake in Suzhou has made new strides as more migratory birds have been spotted in the surrounding wetlands.

Wang Haiying, researcher at the Academy of Environmental Planning and Design of Nanjing University, said more than 10,000 birds in 59 species have been found to spend winter in wetlands including critically endangered species under state protection.

Since September last year, Wang and his team have conducted three surveys around Suzhou Industrial Park. After arriving at Yangcheng Lake, waterfowl like ducks and geese will stay for about three months before flying back to north at the beginning of the spring. Wang said it's very exciting to come cross rare species just like opening a mystery box.

Baer's pochard (Aythya baeri) is a kind of diving duck that has high requirements for habitat and is considered an indicator species to evaluate the environmental condition. The bird may fly away after getting frightened or not come back the next year, according to Wang. So the finding of the diving duck means a safe and stable environment with sufficient food.

In 2021, Suzhou launched a pilot project to restore aquatic vegetation in Yangcheng Lake, expanding the water body with vegetation cover to 8,000 mu (about 530 hectares) as of July 2022. The water transparency increased from 0.68 meters to 0.96 meters, the total biomass of zoobenthos such as mussels and shrimps gradually increased, and the number of migratory birds jumped by about 5,000.