Hi Rick,

How about Hutton's Vireo? It would seem to fit your
description in most ways. Certainly the call you describe is
right. The upright posture isn't really typical of Hutton's
Vireo in my experience but if the bird was agitated and issuing
it's scold note it may have been in more of a "heads-up" posture
looking around it's environment.
The new Pyle "Identification Guide to North American
Birds, Vol. 1" describes the stephensi race of Hutton's Vireo
(resident in AZ and NM) as pale grayish-olive on the crown with
underparts "...(including the flanks) whitish with an olive tinge."
Although it describes the eye ring and wing bars as "distinct
and whitish" it could be that the bird you saw may have been in
a worn alternate plumage.
Of course there are other vireos to consider such as
Bell's, Gray and Plumbeous. I saw the the first two of that trio
when I was in Arizona but am not familiar ehough with their
plumages or calls to say anything about them....

Jim Flynn
Renton, WA
bf519 at scn.org
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