Identification

Typical ibis shape (long legs, relatively long neck, and a long, decurved bill) with black and buffy-orange plumage. Its plumage is described by Collar and Bird (1 Collar, N. J., and J. P. Bird (2011). Phenotypic discrimination of the Andean Ibis (Theristicus branickii). Wilson Journal of Ornithology 123(3):459–463. Close ) as: "rufous-chestnut of the crown continuing smudgily onto the face and back to a broad area of the upper neck; shows short lines of bare black skin on the submoustachial and malar area and a fully feathered chin and throat, and has a white belly-patch between the gray breast-line and the black underbelly." Lacks white on wing. Paler than similar Black-faced Ibis (Theristicus melanopis), less ochraceous foreneck and breast, and usually smaller area of bare skin on throat (1 Collar, N. J., and J. P. Bird (2011). Phenotypic discrimination of the Andean Ibis (Theristicus branickii). Wilson Journal of Ornithology 123(3):459–463. Close ; see Similar Species).

Similar to Black-faced Ibis, which sometimes co-occurs with Andean Ibis in lowlands valleys in Chile and Peru. The differences are well-described by Collar and Bird (1 Collar, N. J., and J. P. Bird (2011). Phenotypic discrimination of the Andean Ibis (Theristicus branickii). Wilson Journal of Ornithology 123(3):459–463. Close ), which are summarized here: compared to Black-faced Ibis, Andean Ibis has the rufous-chestnut coloration on the crown extending onto the upper neck and face in a smudgy pattern, whereas Black-faced Ibis has a sharp demarcation between the rufous-chestnut crown and the pale buffy-yellow face, and the rufous-chestnut reaching only the nape and not extending further down the neck. Further, Andean Ibis has a distinctly whitish upper belly, which is also more extensive than the rusty-buff colored upper belly of Black-faced Ibis. In addition to the plumage differences, Andean Ibis also has a much shorter bill and longer tail than Black-faced Ibis, and also lacks the bare wattles on the chin/throat; the bare patch on the throat of Andean Ibis is much smaller than in Black-faced Ibis, and is restricted to short lines in the malar and submoustachial area, while the throat and chin is entirely feathered.