Paul Barrett reported a Yellow-throated Vireo on the Fowler trail just west of the Bastille in Eldorado Canyon yesterday.
I am not an expert and do not have the calls memorized, but thought it was worth noting that I saw a bird with a bright yellow head and breast region on June 2 that was the size and appearance of a vireo just southeast of where the Red Headed Woodpecker has been seen, east of that ridge and near where the trail splits to go contour up the slope or wrap around the ridge. It was singing and I then got a good look but didn't have my camera. The only thing is I thought there was yellow just before the tail on the underside which would better match a Pine Warbler but the song was more in line with the Vireo. Because of the uncertainty I am not reporting it on e-Bird but thought it was worth noting that I saw a yellow rarity not far from Paul's report.