The Prothonotary Warbler (Protonotaria citrea) is a small songbird of the New World warbler family. It is the only member of the genus Protonotaria.It breeds in hardwood Swamps in extreme southeastern Ontario and eastern United States. It is the only eastern warbler that nests in natural or artificial cavities, sometimes using old Downy Woodpecker holes. The male often builds several incomplete, unused nests in his territory; the female builds the real nest. It lays 3-7 eggs. It winters in the West Indies, Central America and northern South America.