Anas superciliosa
The Pacific Black Duck measures 50 to 60 cm in length. It is mostly mid-brown in colour, with each feather edged buff. The head pattern is characteristic, with a dark brown line through the eye, bordered with cream above and below and a dark brown crown. The upperwing colour is the same as the back, with a bright glossy green patch in the secondary flight feathers. The white underwing is conspicuous in flight. Young Pacific Black Ducks are similar to the adults in plumage.
Pacific Black Ducks are usually seen in pairs or small flocks and readily mix with other ducks. In the wild, birds are often very wary of humans and seldom allow close approach. Birds in urban ponds become quite tame, however.
The Pacific Black Duck is closely related to the Mallard, A. platyrhynchos, introduced into Australia from the Northern Hemisphere. The two species are very similar in habits and occupy the same niche in the two regions. The two species will interbreed in situations where Mallards have been released.
The Pacific Black Duck is one of the most versatile of the Australian ducks. It frequents all types of water, from isolated forest pools to tidal mudflats, and is found in all but the most arid regions of Australia. Outside Australia, its range extends throughout the Pacific region.
The Pacific Black Duck is mainly vegetarian, feeding on seeds of aquatic plants. This diet is supplemented with small crustaceans, molluscs and aquatic insects. Food is obtained by 'dabbling', where the bird plunges its head and neck underwater and upends, raising its rear end vertically out of the water. Occasionally, food is sought on land in damp grassy areas.
The breeding season of the Pacific Black Duck is highly variable. Mating coincides with availability of sufficient food and water, and often with the onset of heavy rains or when waterways are at their peaks. Courtship is accompanied by ritualised displays including preening, bobbing and wing-flapping. This behaviour is often initiated by the female, and, other than copulation, the male helps little in the breeding process. Often, two broods will be raised in a year, with as many as 16 eggs in each clutch. These numbers may seem quite high, but only 20% of these offspring will survive past two years of age.
Copyright © Australian Museum, 2003
This page: http://www.amonline.net.au/factsheets/pacific_black_duck.htm
