The reindeer live in herds in the arctic regions, and they are perfectly adapted to this: They can survive in areas with temperatures down to -40 degrees celsius, and they keep the herd together in a snowstorm by listening to each other - the reindeer has a tendon in their legs that "click" when they walk.
The reindeer is different from the other nordic species of deer, in the way that both males and females have antlers. The males antlers are the biggest, and they shed them in December-January, while the females shed theirs in may. This way only the females have antlers during the winter and that ensures that they can get acces to more food, in the period where their featus grows.
It's allowed to feed the reindeer - but remember: you are only allowed to use the custom made feed which can be bought in the entrance.