The Black-capped Donacobius is a familiar sight in marshes and wet pastures across much of South America, often calling attention to itself with loud, duetting calls. This distinctive bird long resisted efforts by ornithologists to classify it. Formerly it was known as the "Black-capped Mockingthrush," when it was thought to belong to the New World family of thrashers and mockingbirds (Mimidae), but it now is recognized as the sole member of a family with affinities to with Old World warblers. Despite being common and widespread, and occuring in open habitats, the donacobius is little-studied; but it is known to be a cooperative breeder.
Black-capped Donacobius
