Mystery Bird: Lapland Longspur, Calcarius lapponicus

I believe that's a non-breeding-plumage Lapland Longspur. It's a bird I'm not familiar with, but the field marks match up well with Sibley: "rufous-edged greater coverts", "broad rufous tertial edges", and "dark frame on auriculars" (what you can see of it). I think this bird looks a little more like a female than a male, at least based on the illustrations I'm looking at, but I'd be interested in hearing from someone who knows the bird better about that.

I agree with John - I also believe this is a Lapland Longspur. I saw many of these in a big flock late last year at Pt. Reyes, and got many close-up pictures. The birds in my pics look like this bird.

Lapland Longspur. Rufous terts and grcovs; supercilium and auricular buffy. Brownish-pink bill in fall=AHY female or HY of either sex.

Yes, as others have posted, this appears to be a non-breeding Lapland Longspur; broad supercilium, rufous coverets; white belly; broad streaks of black; can't see breastband. It's not breeding as it doesn't have a black face and the bill is not yellow.