The Willow Warbler (Phylloscopus trochilus) is a small, slender songbird with olive-green upperparts and pale underparts. Common across Europe, it breeds in woodland and scrub, migrating to sub-Saharan Africa for winter. It is very similar to the Chiffchaff, but has paler pinkish-yellow legs (dark brown to blackish in chiffchaff), longer paler bill, more elegant shape and longer primary projection (wingtip)