Moss-backed sparrow Arremon dorbignii

Boldly-patterned sparrow found in montane forests from Bolivia to northwestern Argentina. Usually in pairs on or near the ground, foraging at the edge of forest. Note the bicolored bill with an orange-yellow lower mandible. Also look for the bold black-and-white head pattern, black chest band, and bright mossy-green back. The song is a series of high-pitched notes.