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
Ptarmigan (sternwheeler) piper, and lifted him unharmed over to the foredeck of "Ptarmigan" while the piper reportedly never missed a note. "Ptarmigan" passed "Gian" and thereafter Cantlie steered clear of the big steamer. "Ptarmigan" was dismantled in 1909. "Ptarmigan"'s engines, which had been under water at least twice when the vessels they powered sank (once with "Ptarmigan", once with the first "Duchess") were installed in another vessel, the "Nowitka". Ptarmigan (sternwheeler) Ptarmigan was a sternwheel steamboat that operated in British Columbia on the Columbia River from 1903 to 1909. "Ptarmigan" was built at Golden, BC and was the last vessel built for