These range from eastern, northern and central Australia across the Top End and Cape York down to southern Queensland and northern New South Wales on the east coast, it is also found in New Guinea. Their habitat is tall grassland and savanna near bodies of water, they have benefitted from pastoral practices which provide dams for water and pasture on which to graze, here they seem to prefer wet grassy areas that are not too open and can sometimes be seen in large numbers. They feed at night on grasslands and rather than diving for food in bodies of water like other ducks they feed by cropping grass on land like geese. Their call is a characteristic whistle which gives the bird its common name.
The sexes are similar in appearance and breeding begins in the wet season, the nest is a mattress of grasses or similar material in tall grass in or near vegetation as cover and in which as many as 10 to 12 eggs are laid These ducks are monogamous and pair-bonds are probably life-long with both sexes sharing the duties of incubation and raising the young.