Common in s. swamps, particularly near water. Early migrant spring and fall. Belts out its song ‘tsweet tsweet tsweet tsweet’ from mosquito-ridden areas. Uusually found higher in smaller trees but often comes lower, occasionally dropping to the ground. A cavity nester that will also use nest boxes. Moves slower than many warblers, almost vireo-like at times. ID: Ann oddly shaped warbler. Big and very fat with a pot belly and short tail. The bill is large and pointed — this stands out, just like its beady eye, against a background of uniform yellow. One color pattern: yellow with a green back, gray wings, and white undertail tipped black. Ad ♂ brightest, 1st-year ♀ dullest, ad ♀/1st-yr ♂ in between.