Posted by Walter Wehtje (4.63.207.234) on June 28, 2003 at 07:28:34:
Looks like a Western X Eastern Kingbird hybrid to me. The bill doesn't look big enough for a Thick-billed Kingbird, while the time of year and location are totally wrong for that species; most vagrant TBKIs occur in fall and winter. Both EAKI and WEKI occur in Wyoming, and the only other likely culprit, Cassin's Kingbird, doesn't occur that far north. I'd also expect some gray on the chest if a CAKI was involved. The tips on the tail indicate a juvenile bird, which makes sense, as the feathers look rather fresh.