Identification: The easiest way to separate Chiffchaff from Willow Warbler is by the black legs of a Chiffchaff but this isn't always reliable. If it's really a Chiffchaff it should have relatively shorter wings, drabber underparts and a rather timid facial expression, as created by a weaker eyestripe, shorter, more rounded head and shorter bill.

Habitat: Breeds in open wooded areas with undergrowth. Winters in parks, gardens and scrub, especially by water.

Distribution: A common summer visitor, with birds arriving from March onwards. Increasing numbers of birds are now wintering, particulary in the south of England. Small numbers of the race P.c.tristis occur annually though there are possibly fewer than are actually claimed.

Widespread and numerous in most of Europe in summer but confined to southwest Europe in winter.

Population: 640 000 territories estimated for Britain with 290 000 in Ireland. Rarer in northern Britain and the Scottish Highlands. About 500 birds probably winter in Britain but in some years this number may reach over 1 000.

15-20 million breeding pairs across northern Europe.