During winter brown bears hibernate, and the bears in Scandinavian Wildlife Park do to. The next generation of cubs are born during hibernation.
The bear sleeps
As the temperature drops and and winter is approaching, the brown bears’ will start to prepare for hibernation. Brown bears go down in their dens in November, and they sleep all the way to March-April. So they sleep almost half a year at a time.
While the bears lie and sleep away from the snow and cold, they neither eat nor drink. Therefore, they can lose up to half their body weight during the winter fasting period. For the brown bears, it is therefore important to get as much fat on the body during the summer months as possible, so that they can get through the winter. A brown bear should eat for a full year in only half the time.
However, the brown bears only burn their fat reserves when they sleep in the winter. Thus, they do not lose muscle or bone mass during their fasting period – they only loose fat. In fact, a brown bear loses about half its body weight during the fasting period.
Hibernation in Scandinavian Wildlife Park
The bears in Scandinavian Wildlife Park have a total of 9 underground dens, all of which are located in the bears’ winter facility. Here, each of the bears has the opportunity to lie down in their own den and hibernate. However, they often choose to go in to the same dens, because it’s apparently a little more comfortable to sleep together throughout the winter.
In Denmark, we rarely experience as harsh winters, as in the areas where brown bears live in the wild. The length of a bear’s hibernation period depends a lot on the temperature, so it varies a lot how often our bears are awake in winter. During an ordinary mild Danish winter, they often sleep 2-3 weeks at a time, wake up a few days and go down and sleep a 2-3 weeks again. If it is a hardh winter they sometimes sleep 2-3 months in a row.
Bear cubs are born during the hibernation period
Down in the den something amazing happens – the little bear cubs are born. Therefore, it is extra important for pregnant female bears to eat well and build up plenty of fat on their bodies before going i nto hibernation. In December, the cubs are born, and both the cubs and the mother are dependent on her fat reserves. This is true for both wild bears and captive bears.
When the babies are born, they are very small compared to their mother. They only weigh approx. 1/2 kg, and the female bear weighs about 200 kg. The bear cubs will spend the first 3 months of their lives in the den, just drinking their mother’s milk. The cubs grow quickly and when they leave the den together with the mother, they no longer weigh only 1/2 kg but 4-5 kg. Usually, a brown bear gets 2-3 cubs, but they can get up to 4.