Blue Grouse divided by two equals Dusky and Sooty Grouse

The state of Washington has a new species of grouse, at least according to the American Ornithologists Union (Auk, 2006, Pages 926-936). Dendragapus obscurus (formerly known as the Blue Grouse) has now been split into 2 species based on genetic, morphological, and behavioral evidence; the Dusky Grouse (Dendragapus obscurus) and the Sooty Grouse (Dendragapus fuliginosus). This split is actually a reversion to the previous situation during the early 1900s when the Dusky and Sooty Grouse were considered distinct.