Would you sparrow me a moment of your time?

[Quiscalus quiscula]

2 hours ago, The Bird Nuts said:

I could be wrong here as I haven't been able to find much information on this, but I don't think you can tell the morph of a winter White-throated.  The spring is when the white-striped morphs start to show their white crown stripes.  Please correct me if I'm wrong.

Huh, interesting. In my experience all the wintering white-striped morphs I've seen still have white crown stripes year round. Also, in the original photo the bird on the right seems to show white crown stripes. I do agree that the left bird is a Swamp now, though.

[Avery]

2 hours ago, The Bird Nuts said:

I could be wrong here as I haven't been able to find much information on this, but I don't think you can tell the morph of a winter White-throated.  The spring is when the white-striped morphs start to show their white crown stripes.  Please correct me if I'm wrong.

Per Birds of the World: 

“During winter, some WS birds (especially females in basic plumage) become duller, plumage color variation is continuous (Atkinson and Ralph 1980), and morph is difficult but still possible to determine with 80-90% accuracy (Piper and Wiley 1991aa). Recently described PCR methods provide 100% accuracy in determining both sex and morph using any sample from which DNA can be extracted…“

[The Bird Nuts]

23 hours ago, Avery said:

Per Birds of the World: 

“During winter, some WS birds (especially females in basic plumage) become duller, plumage color variation is continuous (Atkinson and Ralph 1980), and morph is difficult but still possible to determine with 80-90% accuracy (Piper and Wiley 1991aa). Recently described PCR methods provide 100% accuracy in determining both sex and morph using any sample from which DNA can be extracted…“

Thanks, that's interesting.  Perhaps I see mostly young birds during the winter.