A Day’s Journey Into Night

By Tao Zihui

August 14， 2020. In the morning. The sun has not yet risen from the Yellow Sea， but three researchers from Beijing Forestry University are already hastening across the mudflats toward a distant tidal channel to observe the migratory birds that visit the area each year.

The tidal flat they are crossing is called Tiaozini. With ni meaning mud and tiaozi meaning strips， the wetland was named after its long sections of estuarine mudflats. Located in Dongtai， Jiangsu Province， it covers 270 square km and makes up part of Jiangsus larger Yancheng Coastal Wetlands.

Day breaks at 5：30 a.m. “Green flag， number 24，” a spoon-billed sandpiper with a tag on its leg is spotted by one of the researchers. This young bird was last spotted by researchers in the Arctic Circle， but this August it has come to China.

A paradise

Tiaozini and its four neighboring nature reserves are included in a 186，400-hectare national environmental protection project known as Migratory Bird Sanctuaries Along the Coast of the Yellow SeaBohai Gulf of China （Phase I）. The UN Educational， Scientific and Cultural Organization （UNESCO） recognizes the intertidal mudflat system protected under the project as the largest in the world and granted it the world heritage status in 2019.

The Yellow River in the north and the Yangtze River in the south have both delivered nutrientrich silt to the wetlands for millennia， creating a biologically productive ecosystem that is not only an important nursery for many marine species， but also a vital habitat for migratory birds.

Many of the bird species that find refuge in these wetlands are endangered， including the redcrowned crane with a wild population of fewer than 2，000. Every December， 40 to 80 percent of the worlds red-crowned cranes descend on the Yancheng Coastal Wetlands to spend the winter.

Migratory birds face many threats to their existence， including habitat-loss and degradation caused by agricultural and coastal development， unsustainable agricultural practices， and illegal poaching. “The pin-point accuracy of their navigational ability is astounding， but their journeys are full of threats and most of these are caused by human activities，” Jia Yifei， a researcher with the Center for East Asian-Australasian Flyway Studies （CEAAF） at Beijing Forestry University， told Beijing Review.