[obol] This weeks birds in hand: photo quiz

[Mike Patterson]

I have information on these birds which is not in the photos, so I
have to be careful....

Subspecies identification of Orange-crowned Warblers is not very
well understood.  Most guides I've seen are either poorly representative
of the subspecies or poorly illustrated.  The subspecies themselves
are strongly clinal.  Most fall individuals and hatch-year/second-year
birds are probably impossible to assign to one subspecies even in hand
with the possible exception of a few adult male _lutescens_.

However, as is true of most ID challenges, reasonably fresh, spring
alternate plumage is the best time to take a whack at subspecific ID's.

Let's start with a classic, male _lutescens_
http://home.pacifier.com/~neawanna/observatory/thisweekinhand/band20080501comp26.JPG

Eye-ring brigh yellow, same color as the super, yellowish green face, little
or no grey in the crown, bright yellow chin and throat.  

Next we have a probable male _orestera_ (based on wing measurements and 
characteristics of the orange in the crown.
http://home.pacifier.com/~neawanna/observatory/thisweekinhand/band20080501comp04.JPG

The first question folks will ask is: can we get to _orestera_ from 
the head shot alone?  Well, there is the whitish eye-ring, which as
Dave Irons rightly points out is not by itself diagnostic.  But if we
combine that with gray auriculars, gray crown extending to the base
of the bill, cream colored throat and the very gray bit of shoulder
that was in the original photo.  We can certainly push this bird
toward the _orestera_ end of the cline.

And once you see the whole bird, the undertail coverts tell the
story.

So, the answers would be (in my opinion):

A. Orange-crowned Warbler (probably _orestera_)
B. Orange-crowned Warbler _lutescens_


David Irons wrote:
> 
> Greetings All,
> 
> I sent the same list of species to Mike in response to his quiz.  However, I don't think
> you can make a strong case for the first bird being a representative of the Rocky Mountain
> subspecies (orestera)  of Orange-crowned Warbler. This subspecies, which is often referred
> to "gray-headed," is not a simple ID based on my recent discussions with several folks
> keen on getting a handle of subspecific ID of Orange-crowned Warblers and sorting out the
> migratory routes of the three main subspecies.
> 


-- 
Mike Patterson               
Astoria, OR                    
celata at pacifier.com  
 
When bad photos happen to good birds
http://www.surfbirds.com/blogs/mbalame/archives/2008/03/photo20080313.html