The Cerulean Warbler (Dendroica cerulea) is a canopy-dwelling wood warbler that breeds in mature hardwood forests in the eastern United States and Canada and winters along the eastern base of the Andes from Venezuela to Bolivia (Hamel 2000). Cerulean Warbler is capable of colonizing second growth, and is expanding its range in parts of the northeastern United States (Hamel 2000), yet the species is sharply declining overall (Sauer et al. 2008). Cerulean Warbler is the fastest declining of the North American warblers and is currently listed as globally Vulnerable (Carpenter 2007; BirdLife International 2006, 2009), meaning it is facing a high risk of extinction in the wild, although it is still glaringly absent from the US endangered species list (USFWS 2007, 2009).