I recently commented on this ID problem on MassBird, pointing out differences in details around the eyes.
Chipping sparrow has very distinct, narrow whitish arcs below and ABOVE the eye, contrasting with darker gray-brown feathers, and broken at front and BACK by the dark eyeline. Simply looking for these distinct white arcs is a good quick ID clue, not shared by any other sparrow. (But don’t go running to your Sibley Guide to look it up, I didn’t appreciate how useful it was until recently, so it’s not illustrated very well in the current edition)
On Clay-colored there are pale feathers all the way around the eye, and these blend into just slightly darker feathers, not contrasting at all above the eye (just a broad pale eyebrow stripe). And there is only a very weak dark eyeline breaking the eyering behind the eye.
This leads to the ‘open-faced’ impression on Clay-colored, since the eye is set in a broad pale area.
After reading my comments, Phil Brown put together a nice comparison of two photos, which you can see on his blog here: http://birdsofessex.blogspot.com/2011/10/sparrow-identification-chipping-clay.html
3 thoughts on “On identifying Chipping and Clay-colored Sparrows”
David, I can not say how much I appreciate this post. I found an out-of-range Clay-colored Sparrow this week, but the best photo I could get of it pretty much only showed the eye, eyebrow and cap. Because of this post I feel much more confident in my ID. But I’m wondering something else about the contrast between the eyebrow and cap. To me it seems that when there’s strong contrast between the two, the cap will be rusty on Chipping and dark brown or blackish on Clay-colored. Meaning if you have a bird with a very bold white eyebrow and dark cap it couldn’t be a Chipping Sparrow. Would you agree that that is another useful way to separate the two?
Would these characteristics be the same in February?
Any hints for distinguishing Brewer’s from Clay-colored? As adults and as hatch years?