Polar bear

THE WORLD'S LARGEST LAND PREDATOR

It is a very special experience to see this Arctic giant in the Arctic Ring here at the zoo.

The polar bear is adapted to the harsh living conditions in the Arctic. The creamy white fur allows the large predator to blend in with the snow-white landscape and at the same time serves as effective protection against the intense cold.

The fur consists of two layers. On the outside, the polar bear is covered with water- and oil-repellent guard hairs, which prevent it from getting soaked and chilled, especially when it is in the sea. Under the guard hairs lies the dense undercoat, which consists of short, woolly hairs that keep the air between the hairs warm. Each individual fur hair has a hollow center filled with air, which heats up and acts as an insulator. Together with an up to 10 cm thick layer of fat under the skin, this gives the polar bear an exceptional ability to retain heat. In addition, small ears, a short tail and large amounts of fur between the claws further reduce heat loss to the environment.

All of this enables the polar bear to survive in areas where the temperature can drop below -50 degrees Celsius.

Polar bears are solitary animals and live most of their lives alone. Only when the females are in heat do adult polar bears briefly seek each other out. The males track down the females using scent sports in footprints and urine – a process that is both energy and time-consuming. Females can travel 50-80 km in a single day.

When a male finds a female, he will often try to keep her within a certain area. If other males are present or appear, this can lead to fierce fights for the right to mate. As a rule, it is the largest and strongest male that wins. He and she stay together for a few weeks before mating is completed. After mating, the fertilized egg goes into hibernation and only implants in the uterus and begins its development during the autumn.

Pregnant females dig themselves into so-called birthing dens in the snow. Here they hibernate while the fetus develops. The cubs are born early in the year, usually one or two, but in rare cases up to four. The female stays in the den with the cubs for almost six months, and during this period neither she nor the cubs leave the den – not even to find food. In the birthing den, the cubs gain weight rapidly and can reach around 15 kg, which is more than 20 times their birth weight! The cubs leave the mother after about 2.5 years. A female polar bear can, if conditions are favorable, have cubs about every three years.