Icterine Warbler Hippolais icterina Scientific name definitions

12·5–14 cm; 11–16 g. Medium-sized warbler with pointed bill , rather large head, feathers of forecrown often raised, and short-looking square-cut tail; long primary projection , about three-quarters or more of length of exposed tertials. Has short and indistinct yellowish supercilium , pale loral area (“open-faced” look); crown and upper­parts greenish-grey, flight-feathers and upperwing-coverts darker grey; edges of tertials and secondaries, to lesser degree also of greater coverts, whitish or pale (in fresh plumage forming rather prominent pale panel on closed wing, but in worn summer plumage panel can be near-absent); all tail feathers with thin pale edges and tips; throat  and underparts lemon-yellow, occasionaly paler yellowish-cream; iris dark; upper mandible greyish, lower mandible pinkish-yellow; legs grey, sometimes with faint bluish tinge. Sexes alike. Immature has greenish-grey of upper­parts slightly brown-tinged, pale wingpanel yellowish-grey or pale greenish, underparts generally paler than adult and very occasionally even off-white without any obvious yellow.

Scandinavia and S Finland E to WC Russia (E side of R Ob) and occasionally N Kazakhstan (1 Gavrilov, E. I., and A. E. Gavrilov (2005). The Birds of Kazakhstan. Abridged edition. Tethys Ornithological Research 2. Tethys, Almaty, Kazakhstan. Close ), S to NE France, Switzerland, Romania and N Balkans (locally), Ukraine, Crimea and region E of Sea of Azov; also isolated population in S Caspian Sea, Iran. Winters in S Africa.

Tall-grown woods of oak (Quercus), birch (Betula), beech (Fagus sylvatica), alder (Alnus) and other deciduous trees, but found also in larger parks and gardens, and in stands of young pines (Pinus) if mixed with broadleaf trees. Prefers open forest, or dense woods with intermixed glades and undergrowth. Lowlands in N of range; on wooded hillsides and mountain slopes to 1500 m in S.

Migratory. Non-breeding quarters in Africa mainly S of equator, from S Uganda and E DRCongo S to Namibia and N & E South Africa. Departs from breeding grounds between end Jul and early Sept, reaching African winter grounds mainly late Sept to Nov; spring return starts in late Feb/Mar, with arrival back on breeding grounds end Apr in S of range and mid-May to mid-Jun in N Europe.

Song  a loud and pleasing mix of shrill or melodious notes and clever mimicry of other birds, delivered with energy, generally at rather fast pace, sometimes slowing to give one well-articulated note or motif at a time, often recognized by recurring nasal “gih-e”, but also by interwoven typical trisyllabic calls; ability to mimic varies individually, best ones can render very realistic sounds of such species as Eurasian Oystercatcher (Haematopus ostralegus), Northern Lapwing (Vanellus vanellus), Eurasian Curlew (Numenius arquata), Common Tern (Sterna hirundo), Tawny Owl (Strix aluco), Eurasian Blackbird (Turdus merula), Whinchat (Saxicola rubetra), etc. Call a cheerful, musical, quick “tey-te-dwee” (or rendered “deederoit”); also single “chek”, and as alarm a drawn-out series of hard notes, “te-te-te-te-te-tek”, rather as corresponding vocalizations of H. polyglotta; in anxiety a softer whistling “dwuee”.

End May to Jul, mostly from Jun; generally single-brooded. Nest  a well-built cup of grasses, plant stems, moss and soft twigs, often covered with pieces of birch bark, lichens, flowers and the like, these partly attached with cobwebs, lined with fine fibres, roots, fur and similar soft material, placed in fork of tree branch, often 1–4 above ground, sometimes up to 7m. Clutch 4-5 eggs  ; incubation mainly by female, period 12–14 days; nestlings fed by both parents, fledge at 13–15 days.

Not globally threatened (Least Concern). Fairly common within much of its range, and quite common in optimal habitats in E Europe; numbers more uneven in N & W. Estimated population in Europe (excluding Russia) in 1990s 1,300,000–1,700,000 pairs, including over 500,000 in Belarus and more than 150,000 in Germany; a further 3,000,000 or more pairs estimated in Russia. Average density in optimum habitats up to c. 1 pair/ha. Has declined in extreme W & SW parts of range, with decreases recorded in parts of Denmark, Belgium, France and Switzerland; in some places this may be due to competition from H. polyglotta, which has spread N & E to become marginally sympatric, but other factors thought to be generally more important. Population in Sweden has increased, and range expanded somewhat, since 1970s. Has bred once in NW Turkey (Bursa), in 1966, and also once in Kazakhstan, in 2011 (2 Wassink, A. (2015). Birds of Kazakhstan: new and interesting data, part 6. Dutch Birding. 37(1): 28–32. Close ).