Largest of the three endemic New Zealand teal species, and the only one that can fly. Predominantly a dark brown color. Male in breeding plumage has green iridescence on the head. Females and juveniles are a uniformly dark mottled brown. Mostly restricted to northern North Island (Northland, Great Barrier Island, and Coromandel Peninsula). Both sexes show bold white eye-ring. Recently reintroduced to Kapiti and Mana Islands and the Zealandia Sanctuary in Wellington. Utilizes stock ponds as breeding and feeding sites, and also margins of small streams with overhanging vegetation. Distinguished from Gray Teal and vagrant Chestnut Teal by red eye and lack of white patches on the upperwing.