Blyth's Reed Warbler

Blyth's Reed Warbler, Acrocephalus dumetorum, is an Old World warbler in the genus Acrocephalus. It breeds in temperate Asia and easternmost Europe. It is migratory, wintering in India and Sri Lanka. It is one of the commonest winter warblers in those countries. It is a rare vagrant to western Europe.

This small passerine bird is a species found in scrub or clearings, often near water, but it is not found in marshes. 4-6 eggs are laid in a nest in a bush.

This is a medium-sized warbler. The adult has a plain brown back and pale underparts. It can easily be confused with Reed Warbler and Marsh Warbler. It is most like Reed Warbler but is greyer on the back, the forehead is less flattened and the bill is less strong and pointed. The sexes are identical, as with most warblers, but young birds are yellower below.

The habitat is different from the reed beds favoured by Reed Warbler or the rank vegetation of Marsh Warbler, this species choosing trees or bushes as songposts. Like most warblers, Marsh Warbler is insectivorous, but will take other small food items including berries.

In the breeding season, the best identification feature is the song, which is slow and repetitive, with much mimicry of other birds, punctuated with scales and typically acrocephaline whistles.