eli5 Why do bears hibernate?

Question

I was watching a documentary on Netflix where I learnt that in harsh winters the Alaskan brown bears go into hibernation. isn’t it that just the cold blooded animals like lizards, snakes and other reptiles go into hibernation because they are unable to maintain their body temperatures during winter? plus they have hair on their body (fur) which protects their body (?).

In: 6

Answer 1

There’s not a lot of food available in winter, and maintaining a warm body temperature, and staying active in deep snow, requires an enormous amount of calories.

They do it to conserve calories.