The Icterine Warbler (Hippolais icterina) is an Old World warbler in the tree warbler genus Hippolais . It breeds in mainland Europe except the southwest. The term icterine refers to its yellowish colouration.
This small passerine bird is a species found in open deciduous woodland with bushes and also parks and gardens, often near water. Four to six eggs are laid in a nest in a tree or a bush.
This is a medium-sized warbler, 12–13.5 cm in length,. The adult has a plain greenish-brown back with a paler wing panel, and yellowish underparts. The bill is slightly orange, strong and pointed, and the legs blue-grey. The sexes are identical, as with most warblers, but young birds are paler on the belly.
Like most warblers, Icterine is insectivorous, but will take other small food items including berries.
The song is a fast nasal babbling incorporating mimicry of other species. The call is described as "teck" or "tec, tec, tec".
It is colloquially referred to by birders as Icky.