Date: 10/8/17 10:38 am From: Larry McQueen <larmcqueen...> Subject: [obol] Re: Off-topic - Yellow-green or Black-whiskered Vireo? (Colombia)
I don’t have a solution, but some comments. I don’t believe this is Black-whiskered. The head plumage is too subdued. B-w is more like Red-eyed in this regard. The same for the bill — too pale. Besides, the bird would be out of habitat and too high. In this photo, the bird does not look yellow enough for Yellow-green, but I have little experience with that species. I would consider a race of Red-eyed, such as the Civi Vireo (considered a separate species by some). I agree that the ‘whisker’ mark is not real. I would also consider that the bird could be sub-adult, which might account for the pale bill. Considering that, maybe an immature Black-whiskered could have a shadow whisker and be out of habitat and too high!
Some people have noted the apparent faint whisker, and with other characteristics, including the strength of the eye-line behind the eye, and the lateral crown-stripe, and conclude that it is a Black-whiskered Vireo.
Others note the large, pale pinkish bill, and faint yellowish wash across the flanks, and conclude that it is a Yellow-green Vireo. The apparent whisker may be an arrangement of feathers that allows grayish feather-bases to show.
I photographed the bird at about 1200 meters elevation on the west slope of the eastern cordillera of the Andes in Cundinamarca, Colombia on August 29, 2017. At that location, Yellow-green Vireo would be more likely than Black-whiskered, the latter being more common further north.
I would appreciate opinion. Currently, I’m leaning toward the Yellow-green Vireo, mainly for the pale bill.