Bell's or Sagebrush Sparrow - AZ, USA (1 Viewer)

These were seen during a local field trip to the "Thrasher Spot" just west of Phoenix. The trip leader called this one a Bell's Sparrow, but after returning home and studying the ID features of Bell's and Sagebrush sparrows, I'm now skeptical (but far from certain either way). To me the lateral throat stripe just doesn't seem thick or dark enough for Bell's, and appears to be the same shade as the head. It doesn't show well on the photos, but there was some back streaking, although without more experience with these species I can't say whether the extent of the streaking favored one species over the other.

FYI, here the expected Bell's subspecies is canescens - much more similar to Sagebrush Sparrow than belli.

Opinions? Apologies for the poor photo quality.

This

http://www.sibleyguides.com/wp-content/uploads/On-separating-Sagebrush-and-Bells-Sparrows.pdf

is probably the best reference for ID'ing these two right now, and I think you're right that Sagebrush seems to fit better, but it's tough to be sure.