The Icterine Warbler (Hippolais icterina) is a yellow-and-olive warbler with blue-grey legs that breeds from Central Europe and Scandinavia eastward through Asia, including southern and central Sweden. It measures 13–14 cm long, with a wingspan of about 21–24 cm and a weight of 10–17 grams, showing olive-green upperparts and a yellow underside — a bright, colourful look for a warbler. The bill is fairly strong and broad and the forehead appears somewhat flattened, giving a distinctive head profile, while the blue-grey legs, upright stance and long wings are further useful marks; a pale panel is often visible on the folded wing.
True to its name, the Icterine Warbler is an accomplished mimic, weaving imitations of other birds — often Barn Swallow, Starling and Pied Flycatcher — into a powerful, fast and highly varied song, considerably more forceful and rapid than the soft phrase of the Willow Warbler, with a characteristic ringing "dee-dlu-ii" recurring throughout. It breeds in deciduous woodland, parks and gardens with dense shrub cover, building a neat, fairly deep cup nest in a leafy bush or low branch, where the female lays 4–5 eggs incubated for about two weeks with both parents helping raise the brood. Feeding on insects and other invertebrates gleaned from leaves and branches, with berries added in late summer, it is a long-distance migrant that arrives late, often not until late May, and departs by August for winter quarters in tropical Africa.
Read about this species in Swedish →