DONGYING, Shandong Province: The Yellow River estuary has witnessed environmental progress in the last decade thanks to effective government measures, local officials said yesterday.

"To date, the freshwater wetland area has increased by 4,980 hectares from 2001. The number of bird species under State protection has increased from 187 in the early 1990s to the current 283, one-fifth of the country's total. Precious wildlife totals 459 different species, twice the number in 1999," said Zhu Xuede, vice-director of Yellow River Delta Nature Reserve in Dongying.

The second longest river in China, the Yellow River originates on the Qinghai-Tibet Plateau, winds its way through eight provinces and autonomous regions, and empties into the Bohai Sea near Dongying, a city in East China's Shandong Province.

Last week cowfish, a wild animal under second-class State protection, reappeared at the estuary in Lijin County. Local oceanography and fishery experts said cowfish had almost died out in previous years due to pollution and water shortage.

"The increasing water flow has contributed significantly to the local eco-system revival," Zhu told China Daily.

"The increase originates from the successful administration and protection of the Yellow River and the rich rainfall along the lower reaches."

The river's Xiaolangdi hydro-electric project in Henan Province, which is second only to the Three Gorges Dam on the Yangtze River in terms of workload, has already prevented more than a billion tons of silt from flowing into the lower reaches since it started storing water in October 1999.

By the end of May the rate of flow at Lijin Hydrology Station, the last station the river passes, was 1,100 cubic metres per second, the largest flow since the 1980s, sources with the Yellow River Water Resources Committee said.

Early in 1992, the central government named the Yellow River Delta Nature Reserve a State-level reserve and invested more than 100 million yuan (US$12 million) protecting its environment.

Since the late 1990s, Shandong has placed the development of the Yellow River Delta as central to its development plans.

Dongying has transformed the 8,000-square-kilometre estuary into a comprehensive ecological nature reserve with parks for birds, wild animals, wetland and pastureland.

The improved environment of the estuary is attracting increasing numbers of tourists. Statistics from Dongying municipal tourism bureau show that in the first five months this year more than 1 million people visited the area, bringing in 624 million yuan (US$78 million) in revenues.