Green pygmy goose


The green pygmy goose is a small perching duck which breeds in southern New Guinea and northern Australia.

Names

Its reconstructed Proto-Pama–Nyungan name is *tiwa.

Taxonomy

First described in 1842 by the ornithologist John Gould, its specific name is derived from diminutive of the Latin adjective pulcher "pretty". It is one of three species in the Afro-Asian genus Nettapus, an ancient and unusual group of ducks. No subspecies are recognised.

Description

Ranging from in length, it is one of the smallest species of duck. It has a wingspan. It has a small bill and compact form. The breeding male has a predominantly dark green back, neck and crown, white cheeks and dark green, pale grey and white scalloped underparts. The tail and primary flight feathers and primary coverts are black, while the secondary flight feathers are white. The secondary coverts are a dark iridescent green. This iridescence is lost outside of the breeding season and the plumage is duller. It exhibits sexual dimorphism, the female has a barred rather than green neck and otherwise resembles the non-breeding male. Immature birds are duller, and have mottled dark brown heads.
The male has a high-pitched whistle and the female a lower-pitched call.

Distribution

The green pygmy goose is found in southern New Guinea and across northern Australia. To the west, it commonly reaches Timor-Leste, where it possibly breeds at Lake Iralalara. It is largely resident, apart from dispersion in the wet season. The habitat is well vegetated lowland lagoons and other permanent fresh waters.

Breeding

The green pygmy goose nests in tree hollows. Eight to twelve eggs are laid and the incubation period is 26 days.