Buff-necked Ibis

Overview

The buff-necked ibis (Theristicus caudatus), also known as the white-throated ibis, is a fairly large ibis found widely in open habitats of eastern and northern South America. It formerly included the similar black-faced ibis as a subspecies, but that species is almost entirely restricted to colder parts of South America, has a buff (not dark grey) lower chest, and lacks the contrasting large white wing-patches.

Summary from Wikipedia, available under CC BY-SA 4.0.