Right about this time every winter when the cold still lingers and the snowflakes keep falling, I begin to wish that I could hibernate the rest of the winter away like the bears do. Wouldn’t it be marvelous to take a nap for 100 days straight . . . to never need to get up to eat, to go to the bathroom, or to exercise? We would become quite the couch potatoes by the time spring rolled around if we lived that way too!
Last month a movie called Paddington came out. It chronicles the adventures of a bear that travels from his home in darkest Peru to find a new place to live in London. Paddington is a type of bear called the spectacled bear and is the only bear native to South America. To learn more about bears and hibernation, we can look a little closer to home. North America is home to several species of bear: the black bear, the brown (or grizzly) bear, and the polar bear.
Last month a movie called Paddington came out. It chronicles the adventures of a bear that travels from his home in darkest Peru to find a new place to live in London. Paddington is a type of bear called the spectacled bear and is the only bear native to South America. To learn more about bears and hibernation, we can look a little closer to home. North America is home to several species of bear: the black bear, the brown (or grizzly) bear, and the polar bear.

The American black bear (Ursus americanus) is probably the most common, with a population of around 600,000 individuals. The way black bears hibernate each winter depends largely upon where they live. When cold weather rolls around, the black bears in Northern Minnesota typically have very few food sources left. They have adapted to an earlier hibernation beginning in September or October. However, black bears in more eastern ranges have adapted to later hibernation beginning in November or December because in early winter, some food is still available to them.
In early autumn, after the bear has fattened itself up as much as possible, it is time to begin building its den. The bear rakes leaves, twigs and other bedding material into a den that it often digs out of the earth with its claws. It makes its enclosure very tight, with just enough room to squeeze in. This helps it retain more heat during the cold winter. During this autumn period, the bear’s body begins to transition to get ready for hibernation. Its metabolic rate and heart rate slow down considerably. |
A black bear begins preparing for hibernation in late summer in a period called hyperphagia. This is a period of excessive eating and drinking. In other words, it’s an all a bear can eat buffet! It eats as many carbohydrate-rich berries and nuts as it can get its claws on. It is not uncommon for a bear to gain 30 pounds each week during this period of time!
By the time snow is flying and no food sources are left, the bear is fattened up and cozy in its den ready to hibernate. It rolls into a tight ball with its forepaws over its face to retain as much body heat as possible. The bear’s body is able to do some pretty amazing things during this period of time!
It reduces its breathing to once every 45 seconds, lowers its body temperature to about 88 degrees Fahrenheit (about 12 degrees lower than normal), and lowers its heart rate to 8 to 21 beats per minute.
It doesn’t eat, drink, or go to the bathroom, yet it does not get dehydrated or build up toxic waste in its body. Instead, a bear’s body recycles waste from the bladder into usable proteins?
The bear can remain like this for several months, until spring thaw occurs and food sources are available again.
It reduces its breathing to once every 45 seconds, lowers its body temperature to about 88 degrees Fahrenheit (about 12 degrees lower than normal), and lowers its heart rate to 8 to 21 beats per minute.
It doesn’t eat, drink, or go to the bathroom, yet it does not get dehydrated or build up toxic waste in its body. Instead, a bear’s body recycles waste from the bladder into usable proteins?
The bear can remain like this for several months, until spring thaw occurs and food sources are available again.
One other amazing feature of a black bear’s hibernation is the fact that a mother bear will give birth to her cubs right in the middle of hibernating! Is it possible for a bear to wake up during hibernation? Absolutely! It may just take a little longer than it would to wake up from normal slumber. The mother wakes up to give birth and intermittently wakes up to care for the cubs during the rest of hibernation. Meanwhile, the new cubs, about the size of chipmunk when born, are left to nurse at her side and grow in a safe environment. By the time spring rolls around, they will be strong enough to face the world outside their den.
In mid-April or early May, black bears wake up from hibernation. If I were a black bear, I would want to run straight to the nearest berry bush and have a feast, wouldn’t you? Actually, it takes about another two weeks for a bear’s metabolism to adjust. When it does begin to eat again, it chooses green shoots, leaves, roots, and grubs that are easier on its empty stomach.
When I look at the big picture of a bear’s hibernation, it’s tempting to think of sleeping the winter away! But just think of how many months you would miss! If you were a bear in Northern Minnesota, you’d miss about 8 months every year! In the end, I think I prefer our human adaptations – bundling up as much as possible! What about you?
When I look at the big picture of a bear’s hibernation, it’s tempting to think of sleeping the winter away! But just think of how many months you would miss! If you were a bear in Northern Minnesota, you’d miss about 8 months every year! In the end, I think I prefer our human adaptations – bundling up as much as possible! What about you?
How to hibernate like a bear - activity
We may not be able to sleep the winter away, but you can try this fun indoor activity to see what a bear’s hibernation might be like!
What You’ll Need:
What to Do:
Pretend that you are a black bear, starting in the summer months and going all through winter hibernation into spring. What will you do in each stage of the year?
1. Summer – You are eating and drinking as much as you possibly can to prepare for upcoming winter!
2. Fall – You are building your den with the pillows and blankets. Make sure to make it big enough to fit into it but small enough that you’ll stay nice and warm!
3. Winter – You are hibernating! Make sure you roll up into a tight ball and put your paws over your nose. If you’re a mother bear, make sure that you wake up every once and a while to take care of your new cubs!
4. Spring – It’s time to wake up from hibernation. Remember, you will be very groggy at first! Take your time waking up. Then, go explore with your new cubs!
- Blankets and pillows
- Bear food (draw it onto cereal boxes and cut it out – be sure to include lots of berries and nuts!)
- Your imagination!
What to Do:
Pretend that you are a black bear, starting in the summer months and going all through winter hibernation into spring. What will you do in each stage of the year?
1. Summer – You are eating and drinking as much as you possibly can to prepare for upcoming winter!
2. Fall – You are building your den with the pillows and blankets. Make sure to make it big enough to fit into it but small enough that you’ll stay nice and warm!
3. Winter – You are hibernating! Make sure you roll up into a tight ball and put your paws over your nose. If you’re a mother bear, make sure that you wake up every once and a while to take care of your new cubs!
4. Spring – It’s time to wake up from hibernation. Remember, you will be very groggy at first! Take your time waking up. Then, go explore with your new cubs!