Polar bears will not be able to adapt to ice-free environments and are likely to starve to death, new research has found. As safe habitats for polar bears continue to shrink rapidly due to the climate crisis’ impact on polar regions, scientists carried out a study to understand whether these majestic creatures can adapt to new environments.
Over three weeks in summer, Canadian researchers closely monitored 20 polar bears, employing collars equipped with video cameras and GPS to gain insights into their behaviour and energy expenditure when stranded on land. The results, published in the journal Nature Communications on Tuesday, reveal a grim reality for these creatures as they grapple with the challenges of a changing environment.
Despite the bears attempting various strategies to maintain energy reserves, such as resting, scavenging, and foraging, nearly all of them experienced rapid weight loss, averaging around 1 kilogram, or 2.2 pounds, per day. This weight loss occurred regardless of whether the bears were actively foraging or conserving energy through extended periods of rest, researchers from western Hudson Bay region of Manitoba, Canada, said.
Charles Robbins, the director of the Washington State University Bear Center and co-author of the study, says adapting to land like their grizzly bear relatives seems unlikely for polar bears.
“Neither strategy will allow polar bears to exist on land beyond a certain amount of time,” Mr Robbins says. “Polar bears are not grizzly bears wearing white coats. They’re very, very different.”
Some adult male polar bears opted to conserve energy by resting, and burning calories at rates similar to hibernation. Others actively searched for food, consuming bird and caribou carcasses, as well as berries, kelp, and grasses.