Blue-winged Warbler (Vermivora cyanoptera)
Above: A Blue-winged Warbler in Washington Co., Maryland (5/5/2010).
Below: A Blue-winged Warbler in Garrett Co., Maryland, where it is an uncommon bird (6/15/2008). It was singing on territory near Jennings Randolph Lake.
Below: Photographed on territory near Smithsburg, Washington Co., Maryland (6/10/2006).
Below: A "Brewster's"-type Golden-winged x Blue-winged Warbler hybrid in Washington Co., Maryland (5/5/2010). Although not exactly a "Brewster's" per se, note the bold yellow wingbars on this individual, making its Golden-winged Warbler genes quite evident.
Below: A "Brewster's"-type Blue-winged x Golden-winged Warbler with more limited yellow, but still enough to suggest to me that this bird has genes from both species. (Washington Co., Maryland (5/5/2010).