Clamorous Reed Warbler
Acrocephalus stentoreus
Clamorous reed warbler is a large song thrush-sized warbler at 18–20 cm. The adult has an unstreaked brown back and whitish underparts. The forehead is flattened, and the bill is strong and pointed. The sexes are identical, as with most warblers. It is very like the great reed warbler, but that species has richer coloured underparts. There are a number of races differing in plumage shades. The migratory northern race has the richest brown upperparts, and the endemic Sri Lanka subspecies is the darkest form.
ID text from Wikipedia, CC BY-SA 4.0
Great Reed Warbler
Acrocephalus arundinaceus
The thrush-sized warbler is one of the largest species in both its current the family Acrocephalidae, and its former family, the "Sylviidae". It measures 16–21 cm (6.3–8.3 in) in length, 25 to 30 cm (9.8 to 11.8 in) in wingspan and weighs 22 to 38 g (0.78 to 1.34 oz). The adult has unstreaked brown upperparts and dull buffish-white chin and underparts. The forehead is flattened, and the bill is strong and pointed. It looks very much like a giant common reed warbler (Acrocephalus scirpaceus), but with a stronger supercilium.
ID text from Wikipedia, CC BY-SA 4.0
Where you might meet both
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