Whistling Heron is present in the lowlands of South America east of the Andes. It has two widely disjunct populations. The northern population occurs in eastern Colombia and in Venezuela. The southern subspecies is distributed from northern Bolivia south through Paraguay and southern Brazil to Uruguay and northeastern Argentina.
The elevational distribution of Whistling Heron extends up to 500 m in Colombia (Hilty and Brown 1986); up to 500 m in Venezuela (Hilty 2003), with a single record at 2300 m (Sharpe et al. 2011); and up to 1700 m (rarely to 2500 m) in Bolivia (Hennessey et al. 2003).
Whistling Heron primarily is resident, although there may be some disperal or local movements (Sharpe et al. 2001).
Distribution outside the Americas
Endemic to the Americas.
Very terrestrial for a heron, Whistling Heron is found in tall dry grass, in pastures, damp grass, wet savannas, flooded fields, and very shallowly flooded situations (generally a few centimeters deep) (Kushlan et al. 1982, Hilty 2003). At night these herons roost in trees (Kushlan et al. 1982, Kushlan and Hancock 2005).
Both populations of birds are thought to have been expanding due to their exploitation of man-made areas such as managed pastures, fields, road edges, and ditches.
Dean, S. (2012). Whistling Heron (Syrigma sibilatrix), version 1.0. In Neotropical Birds Online (T. S. Schulenberg, Editor). Cornell Lab of Ornithology, Ithaca, NY, USA. https://doi.org/10.2173/nb.whiher1.01