Preparing for Winter: The Effect of Hibernation on Bear Behavior

With winter approaching, concerns about encountering bears in the wild become less of a priority. After all, you are not likely to run across a bear in the winter if the bear is in hibernation. Prior to winter, however, these same bears actually become more active as they hunt for food and drink in preparation for the long winter ahead. This lesser-known process, called hyperphagia, also has an impact on bear behavior and the amount of risk you face when encountering a bear in the wild.

What is Hyperphagia?

Hyperphagia is the bear process of putting on weight in order to prepare for winter and hibernation. During the fall months before winter, bears eat and drink at a nearly nonstop pace in an effort to put on these extra pounds. As such, bears tend to be very active in the fall, giving national park visitors greater opportunities to see the bears in action. At the same time, this extra activity increases the likelihood of encountering a bear. As such, it is even more important than ever to ensure food is locked away in a bear-resistant food storage locker and waste is safely deposited in a bear-resistant receptacle. Not only does this keep people safe, but it also helps to protect the bears by ensuring they do not lose their preference for natural food or their fear of humans.

What is Hibernation?

Hibernation is a period of time during which the bear is in a deep sleep during the winter. This deep sleep is meant to help the bear save energy and to survive the winter without needing to eat much. During hibernation, the bear’s body temperature drops, its breathing slows and the speed of its heartbeat is reduced.

The length of the hibernation period depends upon where the bear lives. In some cases, hibernation can last only a few days, while hibernation in other areas can last a few weeks or even a few months. Contrary to popular belief, bears may get up and move about at times during hibernation. In fact, pregnant bears will give birth to their cubs while in hibernation. Typically, this occurs within the first two months of hibernation.

In addition to feeding on a regular basis, bears will make and prepare their dens in preparation for hibernation. Bears may make their dens under the root mass of a tree, in a hollow tree or log, in a rock crevice or even in a tree. During this time, their bodies use the fat that they stored in the summer and fall for energy.

When a pregnant bear gives birth to her cubs in her den, the family typically remains in the same den for the duration of the winter. During this time, the mother sleeps as the cubs nurse and grow. When the snow melts in the spring, the bears wake up and resume their search for food. Once again, it is important to ensure all food and waste is properly secured in order to ensure the safety of people as well as the animals.