Spinifex pigeon

The Spinifex pigeon (Geophaps plumifera), also known as the plumed-pigeon or gannaway pigeon, is one of three endemic Australian bird species within the genus Geophaps. It occurs within a broader group known as bronzewing pigeons. This species is listed under the International Union for Conservation of Nature (IUCN) Red List category of "least concern".

Taxonomy

John Gould described the Spinifex pigeon in 1842 and there have been several revisions at both the species and subspecies level. The current taxonomy was determined through a comprehensive examination of twelve variables in 712 specimens from 54 localities. Three subspecies are recognised:

The plumage is distinctively rufous-brown with thin black bars on the wings and back. The forehead, sides of crown and ear coverts are grey and the bill is black. The facial markings are bold and distinctive, a bright red facial mask is bordered by a black supercilium and moustachial stripe. A white band extends from the chin to behind the eye and the throat is black. A white stripe is present on the breast, and the legs and feet are grey. It occupies environments which often experience extreme heat during the day, extreme cold during the night, high seasonal fluctuations in rainfall, and extended periods of severe drought. This species is most often encountered in habitats containing hummock forming grasses of the Triodia and Plectrachne genera, which are colloquially referred to as 'spinifex grasses'.

Behaviour

This species is considered gregarious and sedentary, restricted to habitats within a few kilometres of permanent supply of surface water. They are most often found in pairs or small groups of between four and twenty birds, however, on a rare occasion, have been recorded in a large flock conservatively estimated to number four hundred birds.

They are more frequently observed congregating around water sources in small groups for drinking prior to and during the hottest parts of the day around mid-morning and noon.

Congregations of larger groups occur during favourable seasonal conditions, with dispersal during less favourable conditions or when numbers build up in good seasons.

This species also has a head-shaking display that appears as a greeting between pairs and in threat to other individuals. The bird assumes a crouched over position with head lowered and crest flattened and thrusts forward shaking the bill and head.

Copulation is performed on the ground. The nest is scratched out in a grass-lined depression on stony ground and may be located within sight of other nesting pairs.

Adaptations to desert environments

Spinifex pigeon inhabit harsh desert environments and must be able to cope with substantial water and heat stress. Their geographic range includes one of the hottest places on earth, Marble Bar, Western Australia, where air temperatures exceed 37.8 °C up to 160 days of the year.

Currently the species is listed on the IUCN Red List as a species of least concern and its habitats are protected in several national parks throughout its range including the Tjoritja/West MacDonnell National Park, Watarrka National Park, Purnululu National Park, Kakadu National Park and Diamantina Lakes National Park.