Bears hibernate during the winter months when food is scarce and temperatures are low.
Bears enter a state of hibernation during the winter months when food is scarce and temperatures are low.
They will usually start going into their dens around October/November and come out around March/April.
Bears will usually find a cave, crevice, or hollow tree to build their den in.
They are very particular about where they decide to den up.
The area needs to be well-protected with an ample food supply that they can wake up part-way through winter for.
Bears will consume an immense amount of food before they go into hibernation.
This allows bears to achieve a long sleep without needing to wake up and eat anything.
They will often gain 200 pounds in weight before denning up!
The Process of Hibernation
As bears hibernate, a bear’s heart rate drops from 40-50 beats per minute to 8 beats per minute.
Their body temperature also drops from a normal 97 degrees Fahrenheit to just 35 degrees Fahrenheit.
Their breathing, in turn, slows from 12-25 breaths per minute down to 4-5 breaths per minute.
This way, they burn much less energy than normal and can effectively “sleep” through the winter.
Bears that don’t properly prepare for hibernation before denning up are in serious danger of not lasting through the entire winter.
In fact, they usually only last a few days before they succumb to starvation and wake back up.
Cons of Why Bears Hibernate
There are claims that bears don’t resort to eating their fellow den-mates if they run out of food, but there are some reports that this does happen on occasion!
Rather than cannibalism, this is actually just one bear accidentally suffocating the other bears in the den with their weight.
Cannibalism or not, this is a practice that can’t be repeated too many times as bear populations are already affected.
However, if a bear does manage to make it through hibernation with all its limbs intact, they’ve got a lot to look forward to!
When they wake up, they’re usually so hungry that they’ll eat almost anything!
This leads to some pretty intense feeding frenzies where the bears will gorge themselves on fish, carcasses, berries, and any other food source available.
After fasting for so long in their winter den, it’s no wonder that they go a little crazy after waking up!
Bears will typically den up for a few weeks at a time every couple of months, so they only actually hibernate for about 4 months out of the year.
This way, unlike some other types of bears, it doesn’t really interfere with their other activities such as mating, raising young, and catching salmon in shallow waters!
The only species of bear that doesn’t den up during winter is the Asiatic Black Bear – they will simply migrate to a warmer climate!
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