The marsh warbler (Acrocephalus palustris) is a bird of central and eastern Europe that winters in the savannah regions of East and South Africa. When breeding it inhabits willows, bushes, nettles and tall plants next to rivers and lakes. At other times it can be seen in cornfields and areas of uncultivated vegetation.
The marsh warbler is up to five inches long. The upperparts are olive brown with a paler rump. The underparts are a buffish white with the throat paler. The upper bill is dark brown and the lower bill flesh coloured. The eyes are olive brown. Males and females are similar in appearance.
Male birds sing a loud musical song, including trills and mimicry, when perched at the top of a tall plant. At other times marsh warblers hide themselves away in the vegetation and are thus rarely seen.
Marsh warblers feed on insects, spiders and berries (when available in autumn).
In England, breeding takes place in June. An untidy nest of dry grass, lined with hairs and rootlets, is attached to upright plants such as reeds or nettles. Four or five eggs are laid which are incubated by both birds for around 12 days. The young birds are ready to fly after 10-14 days.