The Common Chiffchaff, or simply the Chiffchaff, (Phylloscopus collybita) is a common and widespread leaf-warbler which breeds in open woodlands throughout northern and temperate Europe and Asia.
It is a migratory passerine which winters in southern and western Europe, southern Asia and north Africa. Greenish-brown above and off-white below, it is named onomatopoeically for its simple chiff-chaff song. It has a number of subspecies, some of which are now treated as full species. The female builds a domed nest on or near the ground, and assumes most of the responsibility for brooding and feeding the chicks, whilst the male has little involvement in nesting, but defends his territory against rivals, and attacks potential predators.
A small insectivorous bird, it is subject to predation by mammals, such as cats and mustelids, and birds, particularly hawks of the genus Accipiter.
The Chiffchaff is a small, dumpy, 10–12 centimetres (4 in) long leaf warbler. The male weighs 7–8 grammes (0.28–0.31 oz), and the female 6–7 grammes (0.25–0.28 oz).