Marsh Warbler
Acrocephalus palustris
This is a medium-sized warbler. It is very similar in appearance to several other acrocephaline warblers, such as the reed warbler which also occurs in wetlands and has a similar breeding range. The male's distinctive song is useful for identification, as no other member of the genus mimics other birds to any significant extent. The marsh warbler also tends to avoid the stands of pure reed which are the reed warbler's favoured habitat. The sexes are alike in appearance. Hybridisation with both reed warbler and Blyth's reed warbler has been occasionally recorded.
ID text from Wikipedia, CC BY-SA 4.0

Sedge Warbler
Acrocephalus schoenobaenus
This is a medium-sized warbler, 11.5–13 cm (4.5–5.1 in) long and weighing around 12 g (0.42 oz). It has a streaked brown back and wings, and pale underparts. The rump is warm brown and unstreaked, contrasting with the duller wings. The forehead is flattened, the crown is streaked with black, and the bill is strong and pointed. There is a prominent whitish supercilium. The legs are greyish. The plumage of the sexes is identical, although they can be told apart when caught for ringing by the presence of a brood patch or cloacal protuberance. Juvenile birds have dark spots on the breast.
ID text from Wikipedia, CC BY-SA 4.0

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Play today's Daily BirdPhotos and recordings are credited to their authors under the licence shown. Full profiles: Marsh Warbler and Sedge Warbler.