Had a wild hair to get some ptarmigan yesterday. You really have to hunt for them in this area of the State, and the flocks are usually in the single digits to teens, rather than hundreds elsewhere. But we do have the whitetail ptarmigan, my favorite of the 3 species (willow, rock, and whitetail).
The whitetails are the smallest by far, and their feathers are pretty much completely white in winter. And they occur at the highest elevations also, I have only found them well above treeline.