system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: What happens if an animal who is supposed to hibernate is unable to?

What happens if an animal who is supposed to hibernate during the winter is unable to because of health reasons or even environmental factors (i.e. home being destroyed by forest fire or being snatched out of environment by poachers)? Does its body wear down and fall into a deep sleep regardless of the severe circumstances? Does the animal eventually get over the need to hibernate after pushing through the normal sleep cycle? Does the animal risk death if it doesn't hibernate?
gpt
A particular example: brown bears. If the bear doesn't get enough chow to get fat before hibernation, it's likely to wake up in the middle of the winter and go about looking for anything to eat. What you get is a шатун, a "rocker", which is willing to kill anything that gets in its way (including armed humans), and is likely to starve to death before spring anyway.