Western Thornbill (Acanthiza inornate) Gould, 1841
195
Family:The western thornbill (Acanthiza inornata) is a species of bird in the family Acanthizidae in the order Passeriformes.
Identifications: Both adult sexes are similar. The upper parts are plain olive-grey, including the wings and tail, which are duskier grey. The tail feathers are tipped narrowly buff except for the center pair. The forehead is scalloped, and the face is flecked with buff white. Underparts are buff-cream flecked faintly grey at the sides of the breast. The eyes are greyish-white. The bill is dusky and paler below. The feet are dusky grey. The immature bird is duller with obscure forehead markings.
Habitats: Probably the least colorful of all thornbills, the Western resembles the Buff-rumped in habits and behavior. It occurs in the same habitats—heathy woodland and close-shrubbed open forest in southwestern Australia, where it replaces the buff-rumped. Both species are thought to have descended from a single ancestor stock that was previously widespread across southern Australia. Dryer conditions separated it and its habitat into two areas in the continent’s southeast and southwest, from which buff-rumped and Western Thornbills emerged.
This little bird with a thin, pointed bill is an active feeder. Western Thornbills forage by hop-gleaning at all levels of the tree canopy, from the lower tree canopy to the ground. The bird spends a lot of time in and among vegetation and ground detritus looking for insects, mostly beetles and bugs. After breeding, the birds form small feeding parties of up to a dozen or so and roam locally, often out into the borders of farmed land and frequently in association with other insectivores.
Nesting and Breeding: Western thornbill nesting and breeding occur in August–December. Nest a dome of grasses and bark strips, with some dried leaves and binding cobwebs. The nest is lined with feathers, fur, hair, or plant down; it is hidden close to the ground behind the loose bark of a tree, in stumps, knotholes, post holes, and even under a tussock of grass.
Eggs: This thornbill usually lays four eggs, pale flesh-white with pale red to rich brown freckles and spots. The eggs are often forming a zone at the larger end; they are oblong-oval, about 6 x 12 mm. The incubation period is about 18–20 days.
Vocalizations: The western thornbill call is rapid ringing staccato twittering in erratic bursts on the same pitch, similar to that of the buff-rumped thornbill.
Distribution:The western thornbill is found in open eucalypt forests, heath, scrubby woodland, and their edges in the southwest of the mainland.
Other Names: It is also known as bark-tit, plain-color red tit, and master’s tit.
Size: The western thornbill measures about 90–100 mm in length.