Here is a pair of Pacific Black Ducks I recently spotted at Marchant Park at Chermside.
The Pacific Black Duck (Anas superciliosa) is a dabbling duck found in much of Australia, New Zealand, New Guinea, Indonesia and many islands in the southwestern Pacific area. 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.
The Australian Museum fact sheet for this bird says that this 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.