White-tailed ptarmigan entry into the respiratory tract. The most obvious adaptation is this bird's cryptic coloration, which enables it to blend in with its environment and avoid predation by golden eagles or other birds of prey. To conserve energy during the winter months, the ptarmigan avoids flight as much as possible and roosts in snowbanks. The white-tailed ptarmigan is listed as being of "Least Concern" by the International Union for Conservation of Nature. This is because, although populations may be in slight decline, its range is too wide and the total number of birds too large to fit the criteria for being
Ocean acidification in the Arctic Ocean simulation predicts that Arctic surface waters will become undersaturated with aragonite within a decade. The undersaturation of aragonite will cause the shells of organisms which are constructed from aragonite to dissolve. This would have a profound effect on a large variety of marine organisms and has the potential to do devastating damage to keystone species and to the marine food web in the arctic ocean. Laboratory experiments on various marine biota in an elevated CO₂ environment show that changes in aragonite saturation cause substantial changes in overall calcification rates for many species of marine organisms, including coccolithophore, foraminifera, pteropods, mussels,