The Yellow River, China's second-longest waterway, is widely dubbed the "mother river" of the country. Now various species of wild birds are also calling the mighty river their home as they choose to settle in the river delta.

The Yellow River Delta National Nature Reserve is located at the river's estuary in east China's Shandong Province, stretching for about 153,000 hectares, with wetlands making up more than 70 percent of its total area. It is an important wintering and stopover site for migratory birds.

The Yellow River Delta National Nature Reserve (Photo: VCG)

Wang Andong, a researcher with the reserve, said 315 oriental storks were born there this year. The oriental stork is a migratory bird under first-class national protection in China and listed as endangered by the IUCN.

An oriental stork (Photo: VCG)

An increasing number of oriental storks choose the reserve to live throughout the year instead of just making brief stopovers, Wang said.

The conservation area has also seen a surge in the population of Saunders's gulls since the species was first spotted in the region in 1992.

A Saunders's gull (Photo: VCG)

The increase in the number of wild birds, especially endangered bird species, reflects the area's improved ecology, said Gou Hongshui, director of the reserve's administration committee.

Gou attributed the improvement to wetland restoration projects in the past two decades, including replenishing water and turning farmland back to wetlands.