Something very unexpected is happening to Norway’s polar bears

Polar bear researcher Magnus Andersen, one of the study’s coauthors, stands in front of a female bear and her cubs in Svalbard. The adult bear was stunned so researchers could take research measurements and samples. | Jon Aars/Norwegian Polar Institute

Polar bears became the poster child for the peril of climate change for obvious reasons: They hunt seals from the ice, and as fossil fuels warm the planet, the ice where these bears live is melting. 

For more than three decades, scientists...