小蝗鶯 Helopsaltes certhiola

Furtive streaky brown warbler; typically buries itself deep in tangled vegetation and is very difficult to see. If seen well, note well-streaked upperparts, long wedge-shaped tail, and rufous rump. Only other well-streaked Locustella warbler in range is the smaller Lanceolated, which has a shorter tail and more extensive streaking on the underparts. Favors wet habitats; breeds in boggy taiga and vegetated riverbanks, winters in reedbeds and marshy fields. Clattering song reminiscent of reed warblers. Call a sharp “tik”; also gives a rapid-fire dry rattle.