Greater Thornbird

The greater thornbird is 19 to 21 cm (7.5 to 8.3 in) long and weighs about 35 to 51 g (1.2 to 1.8 oz). It is heaviest and reddest thornbird. The sexes have the same plumage. Adults have a mostly rufescent brown to grayish brown face with a paler supercilium and ear coverts and a whitish malar area. Their crown is reddish chestnut with pale streaks, their back rich reddish brown to olive-brown that sometimes becomes chestnut on the lower back, their rump a lighter rufescent brown, and their uppertail coverts chestnut. Their wings are a nearly uniform rufous-chestnut and their tail reddish chestnut. Their throat is whitish, their breast pale with a light brownish tinge, their belly whitish, and their undertail coverts light rufescent brown. Their iris is light yellow to orange, their maxilla blackish to dark grayish horn, their mandible pale gray to grayish green, and their legs and feet gray to olive. Juveniles have a less defined crown patch than adults and brownish mottling on their breast.

The greater thornbird is found in north-central and eastern Bolivia, from Bolivia east in Brazil to western Pernambuco and Bahia and south into Rio Grande do Sul, through central Paraguay into northern Argentina as far as Corrientes Province, and into western Uruguay. The species inhabits a variety of landscapes, almost always near water. These include thickets along watercourses, gallery forest, the borders of marshes, and scrublands. In elevation it mostly occurs between 300 and 1,100 m (1,000 and 3,600 ft) but locally reaches 1,400 m (4,600 ft) in Bolivia.

The greater thornbird feeds on a wide variety of arthropods. It usually forages in pairs. It captures prey by gleaning from the ground or from vegetation as in the forest's understorey.