They’re known as pizzlies or grolars, and they’re a fusion of the Arctic white bear and their brown cousins. It’s a blend that’s been turning up more and more in parts of Alaska and Western Canada.
Intraspecies mixing between the two happened thousands of years ago, thanks to the advance and retreat of glaciers, and of late, it has been boosted by climate change. Scientists say it’s also probably been assisted by policies that protect both bears from culling and hunting, affording further opportunities for mingling.
Polar bears are getting the short end of the stick in this relationship, not “gaining any genetic diversity,” said Geoff York, who led research on polar bears at the World Wildlife Fund for almost a decade before joining Amstrup at PBI.
“I hate to say it, but from a genetic perspective, it’s quite likely grizzly bears will eat polar bears up, genetically,” he told me. And he says the changes are already at play.
Right now, polar bears are also threatened by polychlorinated biphenyls, or PCBs, and other toxic pollution — primarily from eating seals and other animals affected by these carcinogens — that has been linked to brain damage, even causing some bears’ baculums, or penis bones, to break off.
