Re: Philly Vireos
GAIL@UMDD.UMD.EDU
Thu, 17 Sep 98 13:49:27 EDT
Hi Marcia --
Actually, the confusion species is Warbling Vireo -- it is about the same size
bird, also has some yellow or yellow wash underneath in fall, and has a
supercilium with a line through the eye. Phillies in fall are usually
completely yellow below, ranging from pale yellow to rather bright, whereas
the yellow on a Warbling is confined to a wash along the sides and under
the tail coverts. The facial pattern of the Warbling is rather "blank" --
the eyeline is faint and the eye conspicious in a plain face, whereas
Phillies have a distinct dark eyeline which gives them a rather "peeved"
expression. Barry and I have seen five Philadelphia Vireos this fall, thanks
to being out in the field a lot, and all were in the company of Red-eyed
Vireos, so it pays to check every one of those Red-eyes. (And if you
are looking from below, recall R-Es in fall generally have a white or
whitish underside but with a pale yellowish wash on undertail coverts).
The three Warbling Vireos we've seen have all been on their own. The latter
species is a local breeder here in Montgomery Co., so these might be
locally dispersing birds and not on long-distance passage, thus not in a
flock.
Now the one we've not seen yet is Yellow-throated Vireo, for some reason!
Gail Mackiernan
gail@umdd.umd.edu