Incredibly Rare: Polar Bear Adopts a Cub

She already had one of her own but, when spotted again, she had another one in tow.

Mother and cubs walk across the tundra | Credit: Dave Sandford / Discover Churchill

When a mama polar bear emerged from her den last spring - in Churchill, Manitoba - researchers noted that she had one young cub by her side. Both were tagged so researchers could keep a track on them. Months later, she was spotted again along with her baby. But this time, she also had another cub beside her.

According to Polar Bears International, polar bears in this region are amongst of the most studied in the world, but they can still surprise experts, and this mama did just that when she adopted a cub that is not her own. To be sure, researchers took genetic samples from the new cub and, sure enough, it was not one of her offspring. Smithsonian Magazine reports that at the end of last year, researchers believed the cubs to be about 10 or 11 months old, and the mother was about 5 years old.

“Polar bear cubs will stay with their moms for between two and two and a half years,” says Alysa McCall, Polar Bears International’s director of conservation outreach and staff scientist. “It's not a lot of time to learn how to be a polar bear. But they do soak up a lot of lessons in that short period of time.”

Polar bear adoptions are considered incredibly rare. In this region of Manitoba, the population has been meticulously studied for over four decades, and in that time, researchers have tracked more than 4,600 individual bears. This new observation marks only the 13th known case of adoption.

The fate of the adopted cub’s birth mother is not known, but there’s a real possibility that the cub is not an orphan. Evan Richardson, a scientist with Canada’s environment and climate change department, says that “because they’re so maternally charged and such good mothers, and they can’t leave a cub crying on the tundra, so they pick them up and take them along with them.” So, it may simply be a lovely act of motherly kindness.

Want to keep an eye on this polar bear and her two cubs? You can track them online.