Hibernation is a time when animals â€˜sleepâ€™ through cold weather. This sleep is not like human sleep where loud noises can wake you up. With true hibernation, the animal can be moved around or touched and not know it. [Donâ€™t you do this, though. Some animals only go into a torpor or temporary sleep time and can wake up quickly. Like BEARS.] We use the word â€˜sleepâ€™ sometimes but hibernation is different from sleep. With normal sleep, the animal moves a little, has an active brain, and can wake up very quickly. With true hibernation, the animal appears dead. There is no movement and it takes a long time for it to wake up enough to even walk around.
During the fall, hibernating animals eat more than usual. Their bodies will live off their body fat as they â€˜sleepâ€™ through winter. The animal will use up the body fat it stores and not lose any muscle. This causes the animal to come out of hibernation thinner but still as strong as it was in the fall.
The animals get their winter nests, dens and burrows ready. Different kinds of animals hibernate in different kinds of safe spots. When they go into hibernation and their bodies slow down, enemies can get them easier. They try to pick the safest place to spend the winter away from these enemies.
Hibernation is the way animals adapt to the climate and land around them. Animals must be able to live through extreme coldâ€¦. or die.
We donâ€™t think about body energy too often. Our bodies are like machines that need power to work right. Food gives animals the energy they need to walk, run, hunt for food, and lots of other things. Hibernating animals store food as body fat during the end of summer and during fall. This body fat runs their bodies all winter. This would be hard to do if they stayed awake, moved around a lot, or ran around because those things would use up the body fat before winter was over. A hibernating animalâ€™s body saves energy by doing a couple of cool things.
When an animal begins to hibernate, its body temperature drops very low so that it almost matches the temperature outside. Your temperature is normally about 98.6 degrees Fahrenheit. If you were a hibernator and it was 30 degrees outside, your body temperature would drop from 98.6 down to about 30-40 degrees. THATâ€™S cold!
The animalâ€™s heartbeat and breathing slow down, too. This is when that stored fat that the animal packed on in the fall comes in handy. This stored fat lasts longer because their bodies are slowed down so much that they donâ€™t need much energy. This is how the animal makes it through the whole winter on the fat it has stored in its body. This is why itâ€™s important for animals to get enough food stored in the fall. If there is a shortage of food at that time, the animal might not live until spring when it can find its food again.
Some of these hibernators also store food in their caves and burrows. The ones that do this do not sleep straight through the winter. They wake up once in awhile, walk around a little, and eat before they go back to sleep.