Willow ptarmigan seeds and berries during the summer and largely subsisting on the buds and twigs of willow and other dwarf shrubs and trees during the winter. The willow ptarmigan is a medium to large ground-dwelling bird and is the most numerous of the three species of ptarmigan. Males and females are about the same size, the adult length varying between with a wingspan ranging from . The weight is . It is deep-chested and has a fairly long neck, a broad bill, short feathered legs and a moderately short rounded tail. In the summer, the male's plumage is marbled brown, with
Ocean acidification in the Arctic Ocean has also allowed more Pacific water to flow into in the Arctic ocean during the winter, this is called Pacific winter water. The Pacific water flows into the Arctic ocean carrying additional amounts of carbon dioxide by being exposed to the atmosphere and absorbing carbon dioxide from decaying organic matter and from sediments. The Arctic ocean pH levels are rapidly decreasing because not only is the ocean water absorbing more carbon dioxide due to increased surface area exposure as a result of a decrease in sea ice. It also has large amounts of carbon dioxide being transferred to the Arctic