yellowstone bison in winter framed by trees

animal bison bovine buffalo horn mammal national park roaming snow wildlife winter yellowstone framed trees outdoors winter snow animal wildlife mammal american bison animals wild nature animal yellowstone park people western usa usa wyoming wilderness horned buffalo wyoming cold temperature brown lamar valley national park sagebrush white color wilderness area montana western usa blizzard landscape scenery bull animal herd environment walking animal themes eating beauty nature nature's window snowing snowcapped mountain non-urban scene river riverbank madison river yellowstone river tree mountain