Found in eastern Queensland, New South Wales, most of Victoria and south-east South Australia with a separate population in south-west Western Australia. Common in south-east and south-west Australia, uncommon in the north.
Feeds by day in fresh water by swimming and on land by walking; prefers deep water with reed margins and grassy banks for grazing. Also found in brackish water of swamps, lakes and estuaries. Eats land and aquatic plants as well as insects, fish, molluscs and worms. In water will up-end to find and reach food. They drink and bathe regularly, often preening one another. At night they use group roosting platforms up to two metres above the water in reeds and shrubs; each bird selecting its own place and standing to sleep. The platforms are used by day for resting.
Dusky Moorhens are sedentary and territorial; they form groups of two to seven birds made up of one to three males to each female. The groups defends the territory during breeding using threat display, calling and fighting. Breeding takes place August to February, often with two broods. Females initiate courtship and mate with all males in their group. All group members build the nest of a substantial, slightly dished platform of aquatic vegetation, usually among rushes or at the base of a tree growing in a swamp. The nest is built by pulling down stalks and using the body to press them into shape.
Five to eight eggs are laid by each female in the group; eggs are laid daily until each clutch is complete. Coloured off-white, with red-brown and grey blotches and spots; shape is oblong-ovate about 53 by 36 millimetres. Incubation takes 19 to 24 days with group members taking turns. Newly hatched young are taken to a second nest over deeper water and brooded there for three days. Then they are led on foraging trips by one adult at a time. For four weeks they are fed intensively and returned to the nursery nest to sleep. Adults cease feeding the young after nine weeks.