A large, carnivorous bear, males weighing 350–700 kg and females half that, with white fur, that occurs throughout the Arctic Basin. Although born on land, it is a marine species and spends much of its time at sea. It feeds mainly on seals, for which it requires broken sea ice between March and June to hunt the young, fat seals on which it gorges, its body storing the fat and allowing it to survive the rest of the year with little food. Males are active all year; pregnant females spend the winter in a maternity den. Polar bear numbers declined drastically due to hunting but have recovered since hunting was regulated in 1973. Of the 19 sub-populations only one (in Western Hudson Bay) has recently been in decline, but it may be recovering, and bears are well distributed throughout their ranges. They are in no danger of extinction.