Tonja looks around with interest before flopping her almost 200 kg weight down and rolling around contentedly in her bedding. Staff at Tierpark Berlin spent several weeks renovating the polar bear’s birthing den: white walls, a new floor, and new technology all give the space the look and feel of the sort of snow cave the bears inhabit in the wild. Today, after a few weeks of acclimatisation, seven-year-old Tonja withdrew to her “cave” for the winter. Newly installed cameras will give the keepers an even better view of what’s going on inside the birthing den without disturbing the bear.
“Tonja clearly feels at home in her renovated winter home,” says polar bear curator Florian Sicks. “For a few days now she has been noticeably more at ease and has barely wanted to leave the box, so as of today she is no longer on view to Tierpark visitors.” However, Sicks points out, it is not yet known whether the female polar bear is actually pregnant: “Baby polar bears are roughly the size of a guinea pig when they are born, so there are no physical signs of pregnancy.”
Zoo and Tierpark Director Dr Andreas Knieriem also has his fingers crossed that Tonja is expecting: “Of course we are all hoping that our polar bears will produce young again soon. This is a threatened species and every cub born is a blessing.”
Five-year-old male polar bear Wolodja can still be seen in the couple’s outdoor habitat. In the Arctic, too, male polar bears spend the autumn and winter alone. Wild polar bears await the colder seasons eagerly, as climate change is making it increasingly difficult for them to find enough food over the summer months. Because of the better hunting conditions in winter, polar bears – unlike their close relatives the brown bears – do not hibernate.
A video of Tonja’s first experience of her new birthing den can be found at:
Video Tonja
