The New Zealand scaup (Aythya novaeseelandiae), also known as the black teal (or in Māori), is a diving duck species of the genus Aythya endemic to New Zealand. They weigh around and measure around , and have dark-coloured plumage. They are found throughout New Zealand in deep natural and man-made lakes and ponds.
New Zealand scaups lay around 7 eggs and the ducklings are immediately capable of diving to feed. Adult scaups can dive to at least 3 metres and for as long as a minute for aquatic plants and invertebrates. Scaups started declining in the late 1800s until they were fully protected in 1934, and their population is now increasing thanks to predator control and new habitat.
Taxonomy
thumb|Watercolour of a male made by [[Georg Forster on James Cook's second voyage to the Pacific Ocean. This painting is the holotype for the species.]]
The New Zealand scaup was formally described in 1789 by the German naturalist Johann Friedrich Gmelin in his revised and expanded edition of Carl Linnaeus's Systema Naturae. He placed it with all the ducks, geese and swans in the genus Anas and coined the binomial name Anas novaeseelandiae. Gmelin based his description of the "New-Zealand duck" that had been described in 1785 by the English ornithologist John Latham in his A General Synopsis of Birds. The naturalist Joseph Banks had provided Latham with a water-colour drawing of the duck by Georg Forster who had accompanied James Cook on his second voyage to the Pacific Ocean. His picture of a male bird was drawn in April 1773 at Dusky Sound, a fiord on the southwest corner of New Zealand. This picture is the holotype for the species and is now held by the Natural History Museum in London. The New Zealand scaup is now placed with 11 other species in the genus Aythya that was introduced in 1822 by the German zoologist Friedrich Boie. The genus name Aythya comes from the Ancient Greek word (), which may have referred to a sea-dwelling duck. The species is monotypic: no subspecies are recognised.
The male has dark black-brown plumage with a striking yellow eye and a dark coloured (greenish) head. The female has duller chocolate brown plumage, brown eyes and has a white face patch during breeding season. A white wing bar can be seen in both sexes when in flight, and both sexes have a grey bill.
The males have a high pitched whistle call and the females 'quack'. It is sometimes seen with the Australian coot (Fulica atra); it is thought that the scaup takes advantage of the food stirred up by the coots as they fossick for shrimps.