My first impression on this bird was juv Sage or Bell's Sparrow, then thought juv. Rufous-crowned Sparrow had possibilities. In looking at some pictures, I was bothered a little by the prominence of the malar for Sage Sparrow. But it does match up for RCSP.
A few other items. The bill looks fairly sturdy. RCSPs tend to have more prominent bills than Sage. The legs are also pretty sturdy and flesh-colored. Sage/Bell's are thinner tarsied and smaller footed, and blacker, although juvs can still be somewhat fleshy. This bird's legs still look more like RCSP. Both subjectively interpretable, but structural and suggestive of RCSP.
Also, the eye-ring is actualy broken in the back, and pretty slight in the front. Sage Sparrows tend to be more prominent in the eyering than this bird, but it looks just like those of Rufous-crowned.
There is a weak but wide gray superciliary going past and behind eye. This pattern holds for RCSP but not for Sage/Bell's. This superciliary will also give the bird a separately colored crown area.
One more item--the tail looks long, and looks more like that of Aimophila--like it will be rounded, rather than squaring out. Also brown rather than having any blackish or gray tones coming in. May not be definitive, but more consistent with Rufous-crowned Sparrow.
Could be wrong, but seems more like RCSP than anything else.
CHEERS, JOE G
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jcwings said:
I would put my money on Rufous-crowned Sparrow. Note the prominent eye ring and dark sub-mustachial marks. Possibly a worn adult or juvenile bird, but I'm not seeing enough streaking on the breast to make me think juvie. It also looks like a Cassin's Sparrow (same genus) but range makes this improbable, although Cassin's has occurred in CA before. Cassin's would have horizontal steaks on the upper side of the tail feathers.
http://www.greglasley.net/Images/Rufous-crowned-Sparrow-F3.jpg