A lone Arctic wolf runs at the large caribou herd, to try and flush out the young or weak. #ArcticWolf #Caribou #DavidAttenborough #NatureDocumentary Subscribe: bit.ly/BBCEarthSub Watch more: Planet Earth bit.ly/PlanetEarthPlaylist Blue Planet bit.ly/BluePlanetPlaylist Planet Earth II bit.ly/PlanetEarthIIPlaylist Planet Dinosaur bit.ly/PlanetDinosaurPlaylist Taken from Planet Earth II. Welcome to BBC EARTH! The world is an amazing place full of stories, beauty and natural wonder. Here you'll find 50 years worth of entertaining and thought-provoking natural history content. Dramatic, rare, and exclusive, nature doesn't get more exciting than this. This is a commercial page from BBC Studios. Service information and feedback: bbcworldwide.com/vod-feedback--contact-details.aspx