The radjah shelduck inhabits the mangrove forests and coastline of [[New Guinea]] ([[Western New Guinea|West Papua]] and [[Papua New Guinea]]) and Australia, and some of the [[Moluccas]] in eastern [[Indonesia]]. In Australia, its primary [[Range (biology)|range]] is coastal, tropical northern Australia, fromextending as far south as central [[Queensland]], west through northernthe upper regions of the [[Northern Territory]] (including [[Kakadu National Park]]) to the [[Kimberley region of Western Australia|Kimberley]] in [[Western Australia]]. The radjah shelduck is listed as a protected bird in all the states of Australia, and penalties existare enforced for harming or disturbing them.
The species prefers the brackishsalty waters of [[mangrove]] flats and [[paperbark]] tree swamps, but will visit all manner of [[brackish]] and freshwater [[swamps]], [[lagoons]], [[Lake|lakes]], [[estuaries]], [[river deltas]], and [[billabong]]s further inland during the wet season.
