Snow camouflage as Hugh B. Cott have echoed his observations, adding that other animals of the Arctic such as musk ox, moose, reindeer, wolverine and raven never become white "even in the coldest parts of their range". Cott noted that both animals that hunt, like polar bear and stoat, and prey animals like ptarmigan and mountain hare, require camouflage to hide from prey or from predators respectively. There is little experimental evidence for the adaptiveness of white as camouflage, though the ornithologist W. L. N. Tickell, reviewing proposed explanations of white plumage in birds, writes that in the ptarmigan "it is difficult
USS Ptarmigan (AM-376) USS Ptarmigan (AM-376) USS "Ptarmigan" (AM-376) was an acquired by the United States Navy for the dangerous task of removing mines from minefields laid in the water to prevent ships from passing. She was the only U.S. Navy ship named for the ptarmigan, a grouse with feathered feet, found in northern regions. "Ptarmigan" was laid down 9 March 1944 by Savannah Machine and Foundry Co., Savannah, Georgia; launched 15 July 1944, sponsored by Miss Jeanne Summerlin; and commissioned 15 January 1945, Lt. Alexander B. Barrett in command. "Ptarmigan" departed for the Pacific Ocean 1 May 1945. Following duty off Hawaii