Well, you're right - with just these two photos a definitive answer may 
not be possible.  For example, I am uncomfortable pronouncing the back 
streaked (and therefore a Blackpoll or a Bay-breasted) or unstreaked 
(and therefore a Pine).  Also, is the mantle a dark green as the top 
photo suggests or almost yellow-greenish as the lower photo suggests?  
The latter color might push us towards Blackpoll (though leg color isn't 
as pale or as orange as one would like for Blackpoll).  Finally, the 
lower photo suggests a touch of buff or bay on the flank (barely 
visible) which of course could close the deal for Bay-breasted.

Another interesting thing to note is the eye which seems to have 
crescents rather than an eyebrow.  To me this is suggestive of a Pine 

If I saw this bird in the field, I am sure it would be readily 
identifiable. However, if I were still on the Bird Records Committee, I 
would be seeking to know how other members would respond to the 
questions I have raised regarding the two photos.

I guess I think the back is streaked - and therefore not a Pine - so if 
a gun were at my head, I would probably go with a bay-breast.

But who knows - maybe the poor thing is a Blackpoll!  Or maybe that back 
isn't streaked after all.


Ernie Buford wrote:
> Here's a Fall quiz bird for you all.  I have my own guess plus an 
> opinion from a member of the bird records committee, but be forewarned 
> that there may not be a definitive answer.  All I have at the moment 
> are these two photos:
> This bird hit a window in Bristol last week and was photographed by a 
> friend of mine.  Which warbler is it, and why?  Give it a shot.
> Enjoy,
> Ernie Buford