EBears have no choice in the changing climate: In summer they eat reindeer, bird eggs, bones, berries and other plants. But that doesn't prevent them from starving. In a summer without ice from which they could hunt fatty seals on the water, they lose up to 1.7 kilograms of body weight per day. The animals lose too much energy when they look for food on land instead of on ice floes.
Biologists from Canada and the USA had fitted 20 polar bears with GPS video cameras on collars and observed them for three weeks in August and early September between 2019 and 2022 (see video). As the researchers in the science magazine “Nature Communications“Report, 19 of the polar bears lost between eight and 36 kilograms of body weight. Until then, science assumed that polar bears on land tried to conserve as much energy as possible and therefore moved little.
Too little energy
Instead, they traveled long distances on land. Some of the bears swam more than 50 kilometers in search of prey. They were unable to eat the carcasses they found in the water or transport them to land. Therefore, the authors of the study consider it unlikely that the animals will be able to adapt to longer summers.
In Hudson Bay in the Canadian province of Manitoba, the habitat of the animals observed, the ice-free period increased by 130 days from 1979 to 2015. Therefore, the polar bears now have to search for food on land for around 130 days a year. The polar bear population in the area has already declined by 30 percent since 1987.
#Arctic #icefree #summer #polar #bears #hungry
