Willow ptarmigan complicated changes in plumage several times a year and the differing colour and pattern of the summer plumage: The willow ptarmigan often hybridises with the black grouse ("Tetrao tetrix") and the hazel grouse ("Tetrastes bonasia") and occasionally with the western capercaillie ("Tetrao urogallus"), the spruce grouse ("Falcipennis canadensis") and the rock ptarmigan ("Lagopus muta"). During the Pleistocene, the willow ptarmigan widely occurred in continental Europe. Authors who recognize paleosubspecies have named the Pleistocene willow ptarmigan "L. l. noaillensis" (though the older name "medius" might be the correct one). These marginally different birds are said to have gradually changed from the
Ptarmigan Tunnel doors were hung across the tunnel adits during the summer of 1975. They remain open from mid-July until October 1, weather permitting. The long tunnel is a unique man-made feature in Glacier. This trail tunnel embodies exceptional qualities of landscape architecture and engineering in a pedestrian-scaled tunnel, cut through a sheer mountain wall. Ptarmigan Tunnel The Ptarmigan Tunnel was built in 1930 through the Ptarmigan Wall at an elevation of in Glacier National Park, near Many Glacier. The tunnel allows hikers to avoid a strenuous climb over very steep terrain between Many Glacier and the Belly River valley. Two opposing