A dusky grouse struts his stuff in a courtship display at Yellowstone's Lake Butte Overlook.

This photo is from a series of our first encounter with him - an encounter in which his eye combs started out bright dark red and moderated from red to orange to yellow over the course of 30 seconds or so.

If your bird field guide is a few years old, or older, you'll find this bird listed as blue grouse. "One of North America’s largest grouse, the Dusky Grouse used to be considered the paler, interior subspecies of the Blue Grouse. Recent DNA evidence supports the spilt of the Blue Grouse into two separate species, the Dusky Grouse and the Sooty Grouse. The male’s deep booming call is hard to locate." http://www.allaboutbirds.org/guide/Dusky_Grouse/id