Lesser Swamp Warbler
I must admit I had great difficulty identifying this species that appeared to be quite common in Ethiopia's Rift Valley Lakes. I identified them at the time as African Reed Warbler, but the books say that this species is near-identical to European Reed Warbler, and this bird does not look like a Reed Warbler to me. It was a bit too big for Reed Warbler but not big enough for the "really big" reed warblers (Great Reed and Clamorous Reed). It is also very cold-coloured, with short wings and almost no face pattern. I initially discounted Lesser Swamp Warbler because it did not look remotely like the book illustration which had rufescent plumage and a strong face pattern. So I resorted to Flickr and looked at the Photostream of Nik Borrow who is a highly respected ornithologist who has lots of experience in Africa. I looked through his warbler album and found he had photos of birds identical to mine such as this: www.flickr.com/photos/nikborrow/25267251108/in/photolist which he identified as Lesser Swamp Warbler. Nik has now seen the photograph and agrees with the identification.
Lesser Swamp Warbler (Acrocephalus gracilirostris) is widespread in the south and east of Africa but becomes very patchily distributed in the north of its range in sub-Saharan Africa. It also has eight named subspecies, four of which are found in Ethiopia. Nik's bird is subspecies parvus photographed at Lake Awassa, where I photographed mine, and I think mine is the same. But looking at most internet photos of Lesser Swamp Warbler I can see why I initially dismissed it as most birds are rufous with a noticeable pale eyebrow (supercilium). But there is no quality control on internet photos so I don't know which of these are correctly identified. Its scientific name gracilirostris means slender-billed, and it does indeed have a slender bill. Parvus means small, so I think this Ethiopian subspecies is probably not as large as the other races further south.
Lesser Swamp Warbler
I must admit I had great difficulty identifying this species that appeared to be quite common in Ethiopia's Rift Valley Lakes. I identified them at the time as African Reed Warbler, but the books say that this species is near-identical to European Reed Warbler, and this bird does not look like a Reed Warbler to me. It was a bit too big for Reed Warbler but not big enough for the "really big" reed warblers (Great Reed and Clamorous Reed). It is also very cold-coloured, with short wings and almost no face pattern. I initially discounted Lesser Swamp Warbler because it did not look remotely like the book illustration which had rufescent plumage and a strong face pattern. So I resorted to Flickr and looked at the Photostream of Nik Borrow who is a highly respected ornithologist who has lots of experience in Africa. I looked through his warbler album and found he had photos of birds identical to mine such as this: www.flickr.com/photos/nikborrow/25267251108/in/photolist which he identified as Lesser Swamp Warbler. Nik has now seen the photograph and agrees with the identification.
Lesser Swamp Warbler (Acrocephalus gracilirostris) is widespread in the south and east of Africa but becomes very patchily distributed in the north of its range in sub-Saharan Africa. It also has eight named subspecies, four of which are found in Ethiopia. Nik's bird is subspecies parvus photographed at Lake Awassa, where I photographed mine, and I think mine is the same. But looking at most internet photos of Lesser Swamp Warbler I can see why I initially dismissed it as most birds are rufous with a noticeable pale eyebrow (supercilium). But there is no quality control on internet photos so I don't know which of these are correctly identified. Its scientific name gracilirostris means slender-billed, and it does indeed have a slender bill. Parvus means small, so I think this Ethiopian subspecies is probably not as large as the other races further south.