This is a typical leaf warbler in appearance, grayish-green above and off-white below. The single wing bar found in the southern and western populations distinguishes them from most similar species (except Arctic warbler P. borealis). It is slightly smaller than that species and has a thinner bill, without a dark tip to the lower mandible.
Habitat and Distribution
It breeds in lowland deciduous or mixed forest; non-breeding birds in the warmer parts of its range may move to montane habitat in summer. Its breeding range is in northeastern Europe and temperate to subtropical continental Asia. This warbler is strongly migratory and winters in India. It is not uncommon as a spring or early autumn vagrant in Western Europe and is annually seen in Great Britain. In Central Europe large numbers of vagrant birds are encountered in some years; some of these may stay to breed, as a handful of pairs does each year in Germany.
Like its relatives, this small passerine is insectivorous.
The nest is on the ground in low shrub.
Calls and Songs
Its song is a high jerky trill, in some populations containing a sequence of down- and more rarely up slurred notes.