Chinese Crested Tern at Chongming Dao, Shanghai, China
by Zhang Kejia, Yu Xi, Gan Xiaojing, David S. Melville from BirdingASIA 2, December 2004.
On the morning of 5 September 2004 we conducted a survey of waders and other waterbirds in the Core Area of the Chongming Dontang National Nature Reserve, Shanghai, China. At 11h27 we saw an adult Chinese Crested Tern Sterna bernsteini on exposed mud near the north branch of the Changjian (Yangtze River) in the northern part of the core area of the reserve (31°34'48.7"N 121°55'12.9"E). The bird was observed for about two minutes using x8 and x10 binoculars and x32 and x20-60 telescopes. Yu Xi is familiar with the bird in the field, having seen (and photographed) three in Fujian in August 2004 (Yu Xi unpublished), and both DSM and Zhang Kejia are familiar with museum materials,
The bird was immediately recognisable by its large size (slightly smaller than a Black-headed Gull Larus ridibundus), very pale pearly grey upperparts that appeared almost white, and conspicuous dull orange bill, the distal third of which was dark. The legs were dark. The bird was in non-breeding plumage with an extensive white forehead extending to the centre of the crown, with a black crest behind. The bird was roosting together with a group of adult Black-headed Gulls, which were moulting out of breeding plumage, and several juvenile White-winged Terns Chlidonias leucoptera. It was seen to fly once when the pale upperparts were very conspicuous. There was no evidence of primary moult. (Two of three specimens in the British Natural History Musem collected in Thailand on 22 November 1923 were in active moult, the third apparently having suspended - all had replaced the inner 6 primaries - DSM unpublished).
This is the first record of Chinese Crested Tern for Chongming Dongtan National Nature Reserve and for Shanghai. The species is Critically Endangered and thought to have a small population (BirdLife International 2000). Breeding was first recorded in the Matsu Archipelago, off the Fujian coast in 2000 (Liang et al. 2000) and a small group was found breeding off the Zhejiang coast in 2004 (Chen Shuihua pers. comm.).
References
BirdLife International (2000) Threatened birds of the world. Barcelona and Cambridge, UK: Lynx Edicions and BirdLife.
Liang, C.T., Chang, S.H. and Fang, W.H. (2000) Discovery of a breeding colony of Chinese Crested Terns. Oriental Bird Club Bull. 32: 1819.