Threatened Species: Polar Bears

The Arctic has started to melt. Where once ice covered the seas and permafrost stabilized the ground, open water and large tracts of barren land will dominate. The consequences for all arctic species will be devastating.

In the southern range of polar bears, for example the Hudson and James Bays of Canada, sea ice is now melting earlier in the spring and forming later in the autumn. The time bears have on the ice is their best season – hunting seals and fish is easy, and they restore their body fat and fitness. But this crucial time for storing up energy for the warm season when there is less ice and little available food is becoming dangerously limited.

As the periods without food lengthen, the overall body condition of these polar bears declines. This is particularly serious for bears that are pregnant or nursing young, and for the cubs themselves. In Hudson Bay, scientists have found the main cause of death in cubs to be either lack of food or lack of fat on nursing mothers.