オニオウギセッカ Bradypterus grandis

A large gray-brown warbler with a long and graduated tail, a white throat, and a heavily streaked upper breast. A highly localized resident in wetlands and swamps with tall sedge, typically within the forest zone; also occurs in adjacent tall grass and forest edge. Secretive and furtive, often creeping around close to the ground within its preferred habitat, but it will also sit up to defend its territory. Sings a strident and distinctive song with 3–4 downslurred “seet” introductory notes that accelerate into a throaty trill. Little Rush Warbler is smaller than Dja River Swamp Warbler and has a different song.