Rare all-black bird found in rainforest east of the Andes, especially near forest-fringed lakes and rivers. Pale blue eye helps separate it from Solitary Black Cacique, which has a dark eye. Might also be confused with Red-rumped Cacique, which often conceals its rump with its wings. It has an amazing vocal repertoire, giving siren-like whistles, metallic squeaks, and catlike squeals, among other calls.