Family Hawks, Eagles (Accipitridae)

Least Concern

Swamp Harrier (Circus approximans)


French: Busard de Gould German: Sumpfweihe Spanish: Aguilucho lagunero del Pacífico
Other common names: Pacific Marsh-harrier, Pacific Harrier, Australasian Marsh-harrier

Circus approximans


, 1848,

Vanua Levu, Fiji


Has been considered a race of C. aeruginosus, from which separated by plumage (see C. aeruginosus). Supposedly larger race gouldi, only slightly darker above and little more heavily streaked below, often considered not worthy of recognition#R. Two subspecies tentatively recognized.

Subspecies and Distribution
  • C. a. gouldi Bonaparte, 1850 – Australia (except arid interior), Tasmania and New Zealand, and Chatham Is.
  • C. a. approximans Peale, 1848 – Vanuatu, New Caledonia and Loyalty Is E through Melanesia and W Polynesia to Tonga.
  • Introduced to Society Is, e.g. Tahiti, in 1885.

    Descriptive notes

    48–61 cm; male 392–740 g, larger female 622–1080 g; wingspan 118–145 cm. A typical marsh harrier, a bulky harrier with long, round-tipped and well-... read more


    Male call in display is a far-carrying and descending "wheeoo", while female version is... read more


    Terrestrial, estuarine and coastal wetlands, grasslands, crops and pasture, from sea level up to... read more

    Food and feeding

    Mammals (especially rabbits on Tasmania), birds and eggs, reptiles, amphibians, fish, large insects and carrion, which latter source is... read more


    Sept–Feb; mainly lays Oct–Dec in Australia. Solitary; rarely polygynous and occasionally polygamous. Undulating sky-dance... read more


    Migratory in S (e.g. virtually entire Tasmanian population vacates the island in winter, especially... read more

    Status and conservation

    Not globally threatened (Least Concern). CITES II. Common in suitable habitat, but local declines where wetlands drained. Nests vulnerable to human disturbance. Only became... read more

    Recommended citation

    Debus, S. & Kirwan, G.M. (2019). Swamp Harrier (Circus approximans). In: del Hoyo, J., Elliott, A., Sargatal, J., Christie, D.A. & de Juana, E. (eds.). Handbook of the Birds of the World Alive. Lynx Edicions, Barcelona. (retrieved from on 6 December 2019).