形态相似的4种杜鹃的鉴别

Identification of Four Sympatric Cuckoo Species in China

大杜鹃Cuculus canorus,中杜鹃C.saturatus,小杜鹃C.poliocephalus和四声杜鹃C.micropterus通过鸣声可快速鉴别,但这4种杜鹃的形态非常相似,在体长、翅长、尾长、喙长等身体量度指标之间的变异范围有重叠或数值非常接近,鉴别困难.为方便野外鉴别,文章给出了这4种杜鹃的鉴别性外部形态特征及其简易图片辨识方法.4种形态相似的杜鹃种类特征如下:四声杜鹃的尾羽具宽阔的近端黑斑,中杜鹃翼下覆羽的横斑少而不显,大杜鹃的腹部横纹细,而小杜鹃的腹部横纹粗.小杜鹃与四声杜鹃可通过体长、翅长和喙长区分,大杜鹃和小杜鹃也可通过翅长区分.

There are up to 17 parasitic cuckoo species in China. Among them, four sympatric cuckoo species, namely common cuckoo Cuculus canorus, Himalayan cuckoo C. saturatus, lesser cuckoo C. poliocephalus and indian cuckoo C. micropterus are too similar in appearance to be recognized, although they are easy to know based on their calls. Here, we provide an easy way for identification of these cuckoos, including picture retrieval of the four cuckoo species. Indian cuckoo＇ s tail is grey with broad subterminal black band tipped white, while Himalayan cuckoo lacks barfing on white leading edge of wings and much darker underwings with fewer white bars and spots; common cuckoo has sharp and narrow underparts white barred black while lesser cuckoo has broader underparts white barred black. As for biometrics, body, wing and bill length of lesser cuckoo are much smaller than those of Indian cuckoo, and wing length of lesser cuckoo is also shorter than that of common cuckoo.