Just a quick morning question in response. This bird is not a tan-striped
phase of the white-throated sparrow? That's what you're comparing it to,
not to a black and white phase WTSP?

--Jerry <tangren at wsu.edu>

>Hi folks,
>
>Got home a bit early this afternoon, so I set up my mist net in my west
>Olympia back yard for an hour. Snagged a couple juncos, a juvenile
>golden-crowned sparrow, and a juvenile Zonotrichia in first-winter plumage
>that stumped me.
>
>I initially thought that it was a juvie white-crowned sparrow, because of
>the solid chestnut-brown lateral crown stripes and trace of buff in the
>grayish median crown stripe. No problem, I thought, just an expected
>juvenile Puget Sound White-crowned Sparrow (Zonotrichia leucophrys
>pugetensis).
>
>But, this bird's had a well-defined white throat, rather than grayish, and
>there were black malar "mustache" stripes, bordering the white throat.
>Aha!, sez I, this is a White-throated Sparrow!! Never having lived in
>white-throated country, I'm not used to the juvenile plumages of the WTSP,
>but my reading of the Zonos in Byers et al. "Sparrows and Buntings" and
>their plate diagram of the White-throated leads me to expect some amount
>of yellow in the loral area - which 'my' bird did not have.
>
>It had a 'straw-colored' (dark orangish-yellow) bill, no streaking on the
>underparts, yellow at the bend of the wing. There was a bit of 'light'
>buff in the loral area, but nothing that approached the supra-loral,
>supercilium stripe of the White-throated Sparrow. In fact, nothing hinted
>at WTSP except the white throat and black 'mustache' stripes.
>
>Is it likely or possible that this is a hybrid White-Throated X
>White-Crowned Sparrow?? After releasing the bird (banded, of course; I
>sketched it and presumed that I'd determine its parentage afterward..), it
>dawned on me that I should have photographed it for a more certain ID, but
>darkness was coming on, and I didn't want to stress the bird more than
>necessary (Science thwarted once again in the interests of compassion to
>the individual....).
>
>If anyone could shed some light on this bird, I'd appreciate it. Without
>more to go on, my inclination is to report this to the Bird Banding Lab as
>a hybrid, but I'm always open to reason
>:-)
>
>Thanks for any help and advice.
>
>Jon. Anderson
>Olympia, Washington
>festuca at olywa.net