Research has shown that polar bears living in Svalbard have demonstrated an astonishing ability to adapt to the conditions of melting Arctic ice. Despite the changing habitat, scientists are still unable to explain how these mammals are adapting, reports the publication "Around the World".
These powerful predators are a striking example of how climate change affects wildlife. Polar bears depend on sea ice for hunting and breeding, yet each year the area of this ice significantly decreases due to global warming.
However, as scientists from the Norwegian Polar Institute discovered with surprise, some populations of polar bears are more resilient to climate change than previously thought. A study, the results of which were published in the journal Scientific Reports, showed that bears in the Svalbard archipelago in the Barents Sea demonstrated the ability to adapt to the reduction of sea ice.
For 24 years, from 1995 to 2019, researchers periodically observed the bears from a helicopter and temporarily immobilized them to assess their physical condition using a measure known as the body condition index or BCI.
In total, more than a thousand assessments of the condition of 770 polar bears in Svalbard were conducted — in a region that has faced particularly sharp declines in sea ice over the past few decades. By 2019, the ice season in this area had shortened by more than two months compared to 1995.
Analysis of the collected data showed that despite the disappearance of ice, the health of the bears did not deteriorate. The lead author of the study, Jon Aars, noted that contrary to expectations, polar bears are in "quite good" condition and have even managed to recover after a decline in BCI from 1995 to 2000, which was an unexpected result for his team.
Nevertheless, this does not mean that the bears are not experiencing negative consequences from the reduction of ice area; some have been forced to change their habitats or move north in search of retreating ice, Aars emphasizes. It is also difficult to say how much better they might feel in conditions without climate change.
Although the results of observations of polar bears in Svalbard may help in studying similar ecosystems, Aars warns that such conclusions cannot be extrapolated to all polar bear populations in the Arctic.
So why do the bears in Svalbard feel relatively well? Scientists suggest that this may be related to changes in their diet. Perhaps the reduction in ice area has made it easier to hunt seals that gather on the remaining ice, or the bears have started consuming more carcasses of walruses and reindeer.
