Whistling Heron Syrigma sibilatrix

The Whistling Heron is endemic to South America, where it occupies two disjunct regions. A northern population, which is smaller and paler, occurs in the llanos grasslands of Venezuela and eastern Colombia, whereas a larger, darker subspecies is widely distributed in the grasslands of southeastern South American, from the pantanal of Bolivia south to southeastern Brazil, Uruguay and northeastern Argentina. The Whistling Heron is one of the least aquatic members of its family and prefers to forage for large arthropods in open wet grasslands.  This bird is named for its distinctive high pitched calls.