White-tailed ptarmigan and development of the chicks. This suggests that the hens' food calls assist in enhancing survival rates of juvenile ptarmigans. The young birds remain with their mother throughout the summer and autumn season. The white-tailed ptarmigan is well-camouflaged when on the ground. In his pioneering 1909 book on the subject, "Concealing-Coloration in the Animal Kingdom", the American artist Abbott Thayer wrote: The white-tailed ptarmigan has feathers located on its feet to serve as protection from the extreme cold often experienced in the alpine tundra environment. In addition, these birds have feathers around their nostrils to warm the air prior to
Arctic ground squirrel Arctic ground squirrel The Arctic ground squirrel ("Urocitellus parryii") is a species of ground squirrel native to the Arctic. People in Alaska, particularly around the Aleutians, refer to them as "parka" (pronounced "par'kee") squirrels, most likely because their pelt is good for the ruff on parkas and for clothing. Subspecies listed alphabetically. The Arctic ground squirrel has a beige and tan coat with a white-spotted back. This squirrel has a short face, small ears, a dark tail and white markings around its eyes. Arctic ground squirrels undergo a coat change from summer to winter. Summer coats include red/yellow colorations along