Vireo gilvus
adult
The Warbling Vireo recalls a plain warbler but has a relatively large head and stout bill. Given the species’ geographical variation (see below), the sexes are similar. Adults have dull greenish-yellow upperparts, subtly darkest on the forecrown. The underparts are pale overall with a faint yellow suffusion to the flanks and undertail. The head has a whitish supercilium and lores, and the wings lack obvious wingbars. Eastern birds (subsp. gilvus) are overall paler and have longer bills than western birds (subsp. swainsoni). Juveniles are similar to their respective subspecies adults but with a more obvious yellow flush to the flanks and undertail.
The Warbling Vireo is present as a breeding species across much of temperate North America, mainly from April to September. It spends the rest of the year in Central America. It is an unobtrusive songbird and usually searches for insect prey high in the tree canopy. Its presence is often initially detected by hearing its distinctive song.
FACT FILE
LENGTH 5.5 in (14 cm)
FOOD Insects and other invertebrates
HABITAT Deciduous riverside woodland
STATUS Widespread and common summer visitor
VOICE Song comprises a series of warbling phrases, with distinct pauses in between. Call is a nasal nrrr
