Published : 20/10/2026
What might Zhuangzi's mythical kun look like in the real world? At sunset over the Yellow River Delta wetlands in Dongying, Shandong, vast flocks rise and swirl across the sky—at times resembling a giant whale, at others drifting clouds—bringing the imagery of Free and Easy Wandering to life.
Autumn and winter are the best seasons to witness this spectacle. But the wetlands once faced a serious ecological crisis. How were they restored, and which birds create these breathtaking formations?
The Yellow River Estuary Wetland
Located at the Yellow River's mouth in Dongying, Shandong, the Yellow River Delta wetlands form a vital part of the delta's wetland ecosystem.
Since the Yellow River shifted course in 1855, its sediment-laden waters have flowed into the sea, gradually depositing new land and creating a landscape of interwoven rivers, mudflats and marshes.
Yet this newly formed land has not always been lush. In some areas, soil salinisation and freshwater shortages left vegetation sparse, while the spread of the invasive smooth cordgrass (Spartina alterniflora) further threatened the wetland ecosystem.
To revive the wetlands, local authorities cleared and reconnected waterways—restoring the "capillaries" between the Yellow River and the marshes.
Ecological water replenishment brought in freshwater to ease soil salinity, alongside programmes to return farmland to wetlands and aquaculture ponds to tidal flats.
Efforts also targeted invasive smooth cordgrass (Spartina alterniflora) and restored native vegetation, including seepweed (Suaeda salsa) and seagrass beds, gradually rebuilding crucial bird habitats.
As water returned and vegetation recovered, migratory birds found more space to feed and rest. Today, in autumn and winter, golden reeds sway in the wind while crimson seepweed carpets the tidal flats.
Birds forage in the shallows or wheel overhead, completing a vibrant ecological tableau.
The Yellow River Delta's bird-wave spectacle
From October to December, the Yellow River Delta wetlands offer one of the best chances to watch migratory birds on the move.
One of the stars of this rolling "bird-wave" spectacle is the Eurasian wigeon—known in Chinese as the "painted-face duck."
In autumn and winter, flocks of Eurasian wigeon arrive at the Yellow River estuary to rest and refuel. As they fly between their roosting and feeding grounds, they take off in unison, forming surging waves of birds.
As the flock rises, turns and circles, its dense silhouettes continually gather and disperse—at times unfurling like drifting clouds, at others rolling like great waves.
In a fleeting instant, they even trace the outline of a giant fish, as though the mythical kunpeng of Zhuangzi's Free and Easy Wandering had entered the real world.
This aerial tableau features more than Eurasian wigeon. Other ducks and waterfowl, including Eurasian teal and gadwall, join the massed flight, weaving together the surging bird waves.
In the winter of 2025 alone, around 200,000 Eurasian wigeon gathered here. From only a few thousand birds in earlier years to the vast flocks now spreading across the sky, the increasingly spectacular displays reflect the Yellow River Delta wetlands' recovering vitality.
In recent years, photographers have captured these fleeting scenes in images and short videos that have spread widely on social media.
The spectacle of "birds becoming kun" has become a popular talking point, drawing visitors to Dongying to look skyward for the moment when a classical Chinese vision meets a natural wonder.
When tens of thousands of wings sweep through the sky, what astonishes is not merely their fleeting resemblance to a giant whale, but the renewed life of the Yellow River estuary wetlands.
The reserve now supports 374 bird species, up from 187 in the early 1990s, and more than six million birds breed, stop over or winter there each year.
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