Common chiffchaff of grasses, bracken, nettles or similar plants. Its breeding habitat is quite specific, and even near relatives do not share it; for example, the willow warbler ("P. trochilus") prefers younger trees, while the wood warbler ("P. sibilatrix") prefers less undergrowth. In winter, the common chiffchaff uses a wider range of habitats including scrub, and is not so dependent on trees. It is often found near water, unlike the willow warbler which tolerates drier habitats. There is an increasing tendency to winter in western Europe well north of the traditional areas, especially in coastal southern England and the mild urban microclimate
Common chiffchaff of London. These overwintering common chiffchaffs include some visitors of the eastern subspecies "abietinus" and "tristis", so they are certainly not all birds which have bred locally, although some undoubtedly are. The male common chiffchaff is highly territorial during the breeding season, with a core territory typically 20 metres (66 ft) across, which is fiercely defended against other males. Other small birds may also be attacked. The male is inquisitive and fearless, attacking even dangerous predators like the stoat if they approach the nest, as well as egg-thieves like the Eurasian jay. His song, given from a favoured prominent vantage