Chestnut-rumped Thornbill
A species of Thornbill Scientific name : Acanthiza uropygialis Genus : Thornbill
Chestnut-rumped Thornbill, A species of Thornbill
Botanical name: Acanthiza uropygialis
Genus: Thornbill
Content
Description General Info
Description
Length: 9.8 cm (9-11); wing span 15.5 cm (14-16.5); weight: 6 g. Mid-sized thornbill similar in size and shape to inland thornbill (A. apicalis) and slaty-backed thornbill (A. robustirostris). Pale and plain with pale iris similar to buff-rumped (Acanthiza reguloides), western (A.inornata), slender-billed (A. iredalei) and yellow-rumped thornbills (A. chrysorrhoa). Pale grey-brown upper, rich chestnut rump and mostly black tail with pale tips, pale mottled ear-coverts and rufous suffusion on forehead and crown. Plain whitish underbody. The sexes are alike, with no seasonal variation. Slight geographic variations, birds of the more arid inland are paler and greyer above, with a slightly paler rump patch and cleaner white below than those in coastal and subcoastal regions. May be confused with other thornbills having a rufous-brown rump patch such as brown thornbill (A. pusilla), inland thornbill (A. apicalis) and slaty-backed thornbills (A. robustirostris). Gregarious usually in small flocks, twos or threes and sometimes with other thornbills and small passerines. Active and restless, the chestnut-rumped thornbill forages in shrubs and trees, searching briskly, flitting and hopping in foliage and low branches, probing into crevices and bark. It also hops on the ground searching among fallen debris. Flight similar to other thornbills, cover to cover in low undulating dashes. Voice is penetrating, with a far-carrying song of similar phrases. It also mimics other birds. Juveniles are similar to adults, but plainer with duller head pattern, and pale buff tail tips, not white. Iris is slightly duller, cream or greyish white. Nearly fledged juveniles have pale yellow gape.
Size
11 cm
Nest Placement
Shrub
Feeding Habits
Chestnut-rumped Thornbill primarily consume insects and occasionally seeds, foraging through foliage, on branches, and on the ground. These birds display gleaning, sallying, and probing behaviors to extract food and are known to feed in small flocks, often with other bird species.
Habitat
The chestnut-rumped Thornbill resides primarily in arid and semi-arid woodlands and shrublands, favoring environments with mulga, mallee eucalypts, and spinifex vegetation. Adapted to both temperate and subtropical zones, these birds are also known to inhabit secondary areas with adequate low cover, such as pastoral lands and roadside verges. Their habitat includes diverse terrain like sand dunes, rocky plateaux, and inland water vicinities.
Dite type
Insectivorous
General Info
Feeding Habits
Bird food type
Distribution Area
Endemic to mainland Australia. Qld: widespread in S, to W of Great Divide, in South Western, South Central and W. South-Eastern Regions. Generally S of 23° S. NSW & ACT: widespread W of Great Divide, including w. slopes of Northern Tablelands and southern Tablelands, Canberra. Vic: Widespread in Mallee, Wimmera and North Districts N of 37°S. SA: Widespread in many regions, but generally absent from SE (though a few records exist). WA: Generally absent from Nullarbor Plain. Farther west largely absent from south coast, widespread in areas W of 123°E from 32°S North to 22°S in Pilbara region. Widespread in Gibson Desert, and scattered sites in Great Victoria Desert.
Species Status
Range: The chestnut-rumped thornbill has an extremely large range, and therefore does not approach the thresholds for Vulnerable under the range size criterion (Extent of Occurrence <20,000 km2 combined with a declining or fluctuating range size, habitat extent/quality, or population size and a small number of locations or severe fragmentation). Population trend: Though the population trend appears to be decreasing, the decline is not believed to be sufficiently rapid to approach the thresholds for Vulnerable under the population trend criterion (>30% decline over ten years or three generations). Population size: This has not been quantified, but it is not believed to approach the thresholds for Vulnerable under the population size criterion (<10,000 mature individuals with a continuing decline estimated to be >10% in ten years or three generations, or with a specified population structure). For these reasons the species is evaluated as least concern. However, the chestnut-rumped thornbill is on a list of declining woodland birds, characterized mostly by being ground or low-shrub feeders and dwellers as well as being predominantly insectivores. The clearing of woodlands on fertile soils and overgrazing of remaining native vegetation, has resulted in fewer ground-dwelling invertebrate prey, causing chestnut-rumped thornbill's range to be possibly contracting towards the inland.
Scientific Classification
Phylum
Chordates Class
Birds Order
Perching birds Family
Australasian warblers Genus
Thornbill Species
Chestnut-rumped Thornbill