This small duck is endemic to the Crozet and Kerguelen islands. It breeds in pairs in summer and may gather in flocks of hundreds in winter.
Its plumage is mostly brown, darker above than below. Breeding-plumage males have a green speculum bordered in white.
In austral summer it breeds in spaced pairs and feeds in small groups. In winter it may gather in flocks of hundreds; its poorly known diet includes plants and small invertebrates.
An extinction-risk assessment has not been added yet.