Kingdom: Animalia
Phylum: Chordata
Class: Aves
Order: Anseriformes
Family: Anatidae
Subfamily: Aythyinae
Genus: Aythya
Species: A. novaeseelandiae
Binomial name: Aythya novaeseelandiae
Common name: Scaup, Black teal, New Zealand Scaup, papango, matapouri, titiporangi, raipo.

The Aythya novaeseelandiae is New Zealand's only diving duck. It can stay underwater for 20 seconds and dive to three metres looking for aquatic plants, small fish, water snails, mussels and insects. It is endemic to New Zealand.
It is found throughout both North and South islands of New Zealand in deep freshwater lakes and ponds. It is present in Taranaki on Lake Rotokare in the Rotokare Scenic Reserve.
Unlike other members of this genus, this Scaup is not migratory, although it does move to open water from high country lakes if they become frozen in winter. They are the smallest New Zealand duck, 40cm long and weighing 650g.
They have an overall dark brown/black colour. The male has a striking yellow eye and a dark coloured (greenish) head. The female is similar to the male, but without the yellow eye and has a white face patch during the breeding season. A white wing bar can be seen in both sexes when in flight.
They are a diving duck and may stay down for twenty to thirty seconds and go down three metres to look for aquatic plants, small fish, water snails, mussels and insects. 
They are social birds and often build their nests close to other nests.  Nesting occurs from October to March. They lay five to eight cream/white eggs in a nest close to water, often under banks or thick cover. The nest is usually lined with grass and down and is hidden under vegetation.  The eggs are incubated for four weeks by the female.

Aythya novaeseelandiae are totally protected.

A male duck with its distinctive yellow iris.
NZ scaup Aythya novaeseelandiae.JPG

NZ scaup Aythya novaeseelandiae-004.JPG 

NZ scaup Aythya novaeseelandiae-002.JPG 
 
NZ scaup Aythya novaeseelandiae-001.JPG 

A female with brown iris.
Female NZ scaup.jpg

A video of the New Zealand scaup diving
VIDEO

Thanks to Wikipedia for text and information     https://creativecommons.org/licenses/by-sa/3.0/