What happens if the inhabitants of the North stop breeding, for example, reindeer?

If the inhabitants of the North stop breeding reindeer, then some northern peoples will simply cease to exist. Deer is a way of life, the basis of survival in the harsh conditions of the Far North for the Nenets, Chukchi, Evenks and others. The Chukchi call themselves “the reindeer people”, translated from the Nenets language, the reindeer is an animal “giving life”. Deer give them food, shelter, clothing. Also, if there is no reindeer husbandry, the number of reindeer will decrease, and the ecosystems of the tundra, forest-tundra and taiga may change.