The Paddyfield Warbler (Acrocephalus agricola) is a species of marsh warbler of the family Acrocephalidae which is in the genus Acrocephalus. It is a summer resident in temperate parts of central Asia. In addition, there are also small breeding populations in eastern Europe along the western shores of the Black Sea around the border between Bulgaria and Romania. It mainly occurs in reed beds, tall grassland and rice fields. This migratory species winters on the Indian subcontinent. Outside its normal range, it occurs as a very rare overshooting autumn migrant to other parts Europe. The closely related Manchurian Reed Warbler (A. tangorum) was formally considered to be a subspecies of A. agricola.
Source: https://en.wikipedia.org/wiki/Paddyfield_warbler