Large, stocky bird. Green-and-chestnut plumage can look mostly black under some conditions and at a distance. Note size, yellow tail, and deep, rowing wingbeats. Reliably distinguished from other green-plumaged oropendolas by pale green-and-red bill. Found in rainforest canopy and edges as well as along rivers, in villages, and in savanna woodlands. Groups move noisily through the forest canopy in search of fruit and flowers. Large flocks are sometimes seen commuting between roosting and feeding areas. Distinctive song of male can be heard at a great distance.