
Photo: Andrey Gulivanov · CC BY 4.0 (May be cropped or resized)
Acrocephalus dumetorum
Habitat
Compact cup of plant material and spiders' webs, 20–60cm above the ground
Clutch size
3–6 eggs
Incubation period
12–13 days, predominantly by the female
Size
12–14cm
Weight
8–16g
Blyth's reed warbler is 12 to 14cm long and weighs 8 to 16g. The pair builds a compact cup nest of plant material and spiders' webs, placed 20 to 60cm above the ground (Wikipedia, general species account).
Between three and six eggs are laid, and both male and female, but predominantly the female, incubate them for 12 to 13 days. The source read for the Bhutan guide gives no plumage, range or diet information, and does not name Bhutan, so none is stated.