The largest of the thornbirds (3), the chestnut-backed thornbird (Phacellodomus dorsalis) has mainly reddish-brown plumage with, as its common name suggests, a chestnut-coloured back. The reddish-brown crown has pale streaking, while the neck and underparts are more greyish-brown, with reddish-brown speckling on the breast and a reddish-brown tinge to the flanks (4).
The males and female chestnut-backed thornbird are similar in appearance (3), while juveniles can be distinguished by the lack of reddish-brown on the crown (4).
The chestnut-backed thornbird has a distinctive iris of either bluish-white or bluish-grey. The long, straight bill of this species is the longest of all species in the genus Phacellodomus (3).
The chestnut-backed thornbird tends to remain hidden, although it often produces rather loud songs (2). The vocalisations of the chestnut-backed thornbird are described as a series of ticking ‘chit-chit-chit-chit-chit’ notes given for long periods with varying intensity. These notes may be given alone, or may accelerate into loud ‘chup-chup-chupchupchuppppp’ notes, which often become quicker at the end (3).
- Length: c. 19.5 cm (2)
- 33 - 39 g (3)