Horned Screamer Anhima cornuta Scientific name definitions

Ponderous, hulking, and sporting a battery of spiky appendages, the prehistoric-looking Horned Screamer more closely recalls a dinosaur than other waterfowl (Anseriformes). It occurs along rivers and in freshwater marshes across much of northern and central South America principally (but not quite exclusively) east of the Andes, extending to southeastern Brazil and northeastern Paraguay.

The characteristic spiny appendage atop the Horned Screamer’s head could rightfully earn it the title of “unicorn of the avian world;" yet, it has several other morphological distinctions, including spurs on its wings that are used for fighting, huge and powerful legs with long toes, and dermal air sacs that can produce crackling non-vocal sounds.

Largely herbivorous, the Horned Screamer forages by grazing and digging at the water’s edge. It tends to aggregate in pairs and in small groups, although it seems to be less social than other screamers (Anhimidae). A consummately vocal bird, pairs can be heard duetting "ha-moo-co" over long periods of time and distances. This clamorous vocalization has inspired many of its regional names, like "Jamuco," "Camungo," or "Aruco."