THE WILLOW PTARMIGAN 



BY JOSEPH GRINNELL 



The name ptarmigan is applied to several species and races of 

 grouse-like birds comprising the genus Lagopus. Lagopus means 

 "rabbit-foot," and refers to the chief character by which ptarmigans 

 are distinguished from other members of the grouse family, namely, 

 the heavy clothing of hair-like feathers which envelop the feet. In all 

 but one of the species remarkable changes of plumage occur twice a 

 year, and by the autumnal one a snow-white dress is acquired for the 

 winter season. This, and the fact that ptarmigans live in the far 

 north or on the tops of high mountains, where the climate is severe, 

 makes appropriate the name snow grouse, used commonly in Alaska. 



North America has three distinct species of ptarmigans. One 

 of them, the white-tailed, lives upon the snowy summits of the Rocky 

 Mountains as far south as northern New Mexico. The rock ptarmi- 

 gan inhabits mountainous country in the far north, and, as repre- 

 sented by various subspecies, is found from Greenland across the con- 

 tinent and on nearly every one of the long chain of Aleutian Islands. 

 The third American species, the willow ptarmigan, with which the 

 present essay is concerned, is most abundant on that level or rolling 

 arctic prairie-land, known as tundra, which lies between the forested 

 interior and the Arctic Coast. In western and northern Alaska, these 

 tundras are covered with a deep layer of moss and lichens. Here or 

 there in 'draws' or shallow valleys, are tracts of dwarf willow and 

 alder. In summer the tundras are boggy, and the many ponds and 

 connecting channels make traveling difficult. In winter they are 

 frozen solidly, and the wind-driven snow packs into the depressions 

 so that the surface is nearly smooth. 



Save for black tail-feathers, almost completely concealed when 

 the bird is at rest, and the black of bill and eyes, the willow ptarmi- 

 gan in the winter is pure white. \A"hen the white feathers first appear 

 in the fall, they possess a perceptible, though faint, tinge of pink; 

 but this soon fades out. 



The purely white winter dress is believed to make the birds so 

 inconspicuous against the white of the landscape that they many 

 times escape discovery by their enemies, the arctic fox and gyrfalcon 

 as they certainly do by the human hunter. On a day when the sky is 

 overcast with dense haze, obscuring the direct rays of the sun and 

 dispersing an intense, even light, the ptarmigans are extremely hard 



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