Common chiffchaff one of the first avian signs that spring has returned. Its call is a "hweet", less disyllabic than the "hooeet" of the willow warbler or "hu-it" of the western Bonelli's warbler. The song differs from that of the Iberian chiffchaff, which has a shorter . However, mixed singers occur in the hybridisation zone and elsewhere, and can be difficult to allocate to species. When not singing, the common chiffchaff can be difficult to distinguish from other leaf warblers with greenish upperparts and whitish underparts, particularly the willow warbler. However, that species has a longer primary projection, a sleeker, brighter appearance
Common chiffchaff The common chiffchaff breeds across Europe and Asia east to eastern Siberia and north to about 70°N, with isolated populations in northwest Africa, northern and western Turkey and northwestern Iran. It is migratory, but it is one of the first passerine birds to return to its breeding areas in the spring and among the last to leave in late autumn. When breeding, it is a bird of open woodlands with some taller trees and ground cover for nesting purposes. These trees are typically at least 5 metres (16 ft) high, with undergrowth that is an open, poor to medium mix