Saunders's gull, or the Chinese black-headed gull, is a Chinese breeding endemic. They only breed in China's coastal regions, but some spend the winter in Japan and South Korea.

The bird is named after the British ornithologist Howard Saunders.

It is the second smallest gull species with a body length of 29-33 centimeters, making it slightly bigger than the little gull but smaller than the relict gull.

Even though it is an aquatic bird, however, the Saunders's gull is a poor swimmer as it has only partially webbed feet.

Rated by IUCN Red List as "vulnerable", the number of mature individuals is estimated to be less than 15,000 worldwide and in decline.

The main threats are the degradation of habitat caused by aquaculture, water pollution and oil production, as it is very dependent on saltmarshes dominated by seepweed.

As strict protection measures have been implemented in recent years at the Yancheng Wetland National Nature Reserve in east China's Jiangsu Province and the Liaohekou National Nature Reserve in northeast China's Liaoning Province, more Saunders's gulls come to these breeding grounds on a yearly basis.

Endemic species are indispensable for the biodiversity of the planet. Their habitat being restricted to a particular area, many of them have yet to be appreciated by the rest of the world. Starting from the precious birds that are endemic to China, this series takes you to the forest, the wild, the sea and the sky.

Birds of China: Elliot's pheasant

Birds of China: Swinhoe's pheasant

(Cover photo was taken by Liu Yong with the Luli Studio.)

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