Research: Polar bears can’t conserve energy during fasting 研究：北極熊無法在禁食期間保存能量
A study of an Alaska polar bear population in summer concludes the bear’s biology will not help stave off starvation in the face of global warming.
The study of southern Beaufort Sea polar bears by university, federal and private researchers over three years concludes they have no special ability to minimize energy loss during increasing periods of fasting brought on by climate warming, less sea ice and fewer hunting days.
The research rejects the idea that polar bears can avoid harmful declines in body condition in a sort of "walking hibernation," as suggested by 1970s research.
The paper published in the journal Science instead concludes that polar bears have no such ability to conserve energy and react like all other mammals when faced with limited food.
Fasting is a way of life for many animals. For polar bears, fasting can last eight months.
Their main prey is ringed seals. Hunting is most successful from April to July when seals use sea ice for rearing pups and molting. In months following, ringed seals spend most of their time in water.
Some polar bears retreat to land, where feeding opportunities are limited, or stay on sea ice that in recent years has retreated far north of the outer continental shelf.（AP）