Bears retreat to winter dens at Korkeasaari Zoo in Helsinki

At the end of October, two bears, aged 18 and 23, were still active, enjoying snacks and stretching their legs. However, by the first week of November, their interest in food and outdoor activity waned, and the sleepy bears retreated into their winter dens, according to Korkeasaari Zoo.

Due to their size, bears find it challenging to forage for food in snowy environments, which is why they can survive northern habitats by hibernating through the winter. For this season, a camera has been installed in one of the bears’ dens to monitor their condition without disturbing them. Both bears are currently in deep sleep; they haven’t moved for a couple of days, reports animal caretaker Susan Nuurtila.

The dens are lined with wood shavings, branches, and moss. During their hibernation, bears may change positions or locations within the den. They often assume various sleeping postures, but the older bear particularly enjoys lying on its stomach with limbs stretched in different directions.

In the autumn, the bears accumulated a layer of fat, which the caretakers monitored through regular weigh-ins. Upon settling into their dens, each bear weighed approximately 225 kilograms. While hibernating allows bears to conserve energy and slow their metabolism, they typically lose dozens of kilograms throughout the winter. Therefore, having a substantial layer of fat is crucial, as the bears usually do not emerge from their dens until February.