Wednesday, February 15, 2012
Photo Quiz Solution
Warblers with yellow extending far back on the face include Townsend's, Hermit, Black-throated Green, Golden-cheeked, and Cape May Warblers. The streaking on the back in many Setophaga warblers (including all five birds above) is often quite dark in adult male birds. This streaking is relatively light, so I'd lean towards a first winter male bird or a adult female bird. All of these species other than Hermit have evident streaking on the flanks in most plumages. These four also all have backs ranging from olive to bright green to solid black (Golden-cheeked). The light gray-olive back and olive crown really suggests Hermit Warbler. And that's what it is.
Here is the same bird, from a more identifiable angle. This bird has no black at all on the throat which concerns me about calling it an adult female. It's clearly not a typical adult male. The upper wing-bar (caused by white-tipped/mostly white median coverts) lacks distinct black centers as far as I can tell (may be washed out or covered by the other median coverts), which suggests this is not a first-winter bird. The brightness of the face is also evidence of an adult bird. Still, the face seems to be more typical of an adult male than female. The crown is olive with only a little black mottling, so adult male seems unlikely, but the very large black centers to the uppertail coverts suggest male! I would lean adult female on this, but I can honestly say I really don't know. I have only seen one other Hermit Warbler than this, and it had black on the throat, so I can't say for sure if this is really that atypical, but it is certainly an interesting comparison to any field guide. Any other ideas on age/sex? Townsend's x Hermit Warbler is a rather common hybrid, but I see nothing intermediate here that suggests that.
Ryan DiGaudio (Top Bird Biologist)