What do reindeer eat in the winter?

Written and fact-checked by The Editors of Encyclopaedia Britannica

In winter reindeer rely on high-carbohydrate lichens called reindeer moss, which they reach by digging craters in the snow. The calf follows its mother and shares this food. The reindeer survive on this low-protein diet by recycling urea (normally a waste product) within the digestive system and making use of its nitrogen.