Dare I report a MOURNING WARBLER from the Western Shore this last day of
July?  

In my limited experience, this sighting was typical of Mourning Warbler
in that it gave only fleeting views as it hid in and on top of a dense
thicket.  The plumage of the bird in question was superficially similar
to the much-more-likely female Yellowthroat -- unmarked olive above (no
wing bars or eye-ring); light, washed with yellow below.  The
underparts, however, showed a sharp demarcation between a completely
gray throat and a yellow breast.  I saw no black on the bird's throat.
The yellow was not bright and was confined to the breast with very
little, if any color on its short under-tail coverts.  I expect a drab
Yellowthroat to be yellow at both ends and gray in the middle, the
inverse of what this bird showed.  I do not see enough Mourning Warblers
to put much confidence on my impressions of shape and size, especially
since the bird's plumage looked ratty.  The location was a rarely-walked
trail at Spice Creek, along the Patuxent River in southern Prince
George's County.

A nesting Mourning Warbler is out of the question for this part of the
state; nor should I expect a migrant as the observation was within atlas
safe dates by a whopping ten hours.

So, does the plumage exclude Yellowthroat as a possible ID?  I think so
but there are all kinds of unusual plumages with which I am not
familiar.  And molt can do weird things to a bird's appearance.  Is this
description sufficient to support Mourning Warbler?  Based on the safe
dates, I'm assuming this would be a record early, or near record early
arrival date for this part of the state so I should take some care with
the ID.

Dave
-- 
David Mozurkewich
Seabrook, PG, MD