the philadelphia vireo (vireo philadelphicus) is a small north american songbird in the vireo family (vireonidae) .
"vireo" is a latin word referring to a green migratory bird , perhaps the female golden oriole , possibly the european greenfinch .
the specific philadelphicus is for the city of philadelphia .
adults are mainly olive-brown on the upperparts with yellow underparts; they have dark eyes and a grey crown .
they have no wing bars and no eye ring .
there is a dark line through the eyes and a white stripe just over them .
they have thick blue-grey legs and a stout bill .
the philadelphia vireo is similar in appearance to the warbling vireo , but can be reliably distinguished by having much yellower underparts , and dark lores .
their breeding habitat is the edges of deciduous and mixed woods across canada .
they make a basket-shaped cup nest in a fork of a tree branch , usually placed relatively high .
the female lays 3 to 5 lightly spotted white eggs .
incubation , by both parents , lasts up to 14 days .
these birds migrate to mexico and central america .
this vireo is a very rare vagrant to western europe .
they are unlikely to visit philadelphia , except in migration .
they forage for insects in trees , sometimes hovering or flying to catch insects in flight .
they also eat berries , especially before migration .
the songs and calls of philadelphia vireo are three to five notes , weeezh weeezh weeezh , very similar to those of the red-eyed vireo .
