

Saw this bird, I think for the first time, this morning. Location north shore of Gross Reservoir, Boulder County, 7600 feet.
Note that it was very early morning, so the rising sun has affected the color somewhat. It paid several visits to my cottonwood tree, searching the buds for breakfast.
Sorry for slightly out of focus image, this bird seems familiar with the autofocus limitations of my camera.
Vocalization was a carefully repeated "kut-ka-chuck, ka-choo, ka-choo, ka-choo" -- not as Sibley describes it for the Bullock's Oriole.
Am I close in my id? At first, I thought it was a Western Tanager just coming into adult plumage, but the throat marking is black, not red.
My guess is first year male Bullock's Oriole.
Any clues?
--Pieter