tags: Pine Siskin, Carduelis pinus, birds, mystery bird, bird ID quiz
[Mystery bird] Pine Siskin, Carduelis pinus, photographed in Arizona. [I will identify this bird for you tomorrow]
Image: Richard Ditch, 16 April 2008 [larger view].
Date Time Original: 2008:04:16 08:46:29
Exposure Time: 1/319
F-Number: 5.60
ISO: 320
Please name at least one field mark that supports your identification.

I'm pretty sure that's a Pine Siskin. The relatively thin, pointy beak and the yellow feathers in the wings and tail are diagnostic.
Yes, Pine siskin - the yellow is a giveaway.