On the Canadian tundra, there is a winter battle looming as caribou bulls seek to assert their dominance. But while the old bull deals with a rival, the young bucks are eyeing up his female… Subscribe: bit.ly/BBCEarthSub #Caribou #Canada #Wildlife Watch more: Best of BBC Earth 🌍 bit.ly/BestOfBBCEarth Best Animal Fights 🥊 bit.ly/BestAnimalFights Videos over 10 minutes ⏰ bit.ly/3SHJCEJ Planet Earth III 🌍 bit.ly/PlanetEarthIIIPlaylist Frozen Planet II ❄️ https:/bit.ly/FrozenPlanetIIPlaylist Blue Planet II in 4k 🌊 bit.ly/BluePlanetII4kPlaylist Taken from 'Earth's Great Seasons' (2016) Every year, spectacular seasons transform our planet. Spring brings new life, but it's also a dash to wake up and get ahead of everyone else. Summer is a time of long days and glorious abundance. But the living isn't always easy when the temperatures rise. Autumn brings the world's most spectacular transformations. It's also the last chance to breed, t...