Chestnut-backed Thornbird

The chestnut-backed thornbird is 19 to 21 cm (7.5 to 8.3 in) long and weighs about 33 to 39 g (1.2 to 1.4 oz). It is the longest member of its genus and has the longest bill. The sexes have the same plumage. Adults have a light gray-brown supercilium that extends beyond the eye and spreads, a thin dark brownish "mask", and dull tawny brownish ear coverts. Their crown is dark gray-brown with dull rufous streaks, their upper back grayish brown blending to their chestnut lower back, their rump grayish brown, and their uppertail coverts reddish brown-tinged grayish brown. Voice: The chestnut-backed thornbird's song is a "series of ticking 'chit-chit-chit-chit-chit' notes given for long periods and varying in intensity, either alone or accelerating and breaking into a loud, even loudsong 'chup-chup-chupchupchupchuppppp' accelerating at the end".