Polar Bear Mother Takes In Youngster in Infrequently Documented Instance

Researchers monitoring free-roaming polar bears in Canada's northern regions observed something remarkably uncommon this fall: a mother bear taking in a cub that was not genetically her own.

The half-decade-old mother and her nearly year-old cubs were observed and filmed during the yearly polar bear journey along the Hudson Bay's western shore near the Manitoba town of Churchill, an locale renowned for its concentration of Arctic bears.

"It's unusual," remarked a researcher with an international bear organization. "The reasons are unclear why it occurs...but we know it is a rare event at all."

This represents only the 13th known case of adoption out of 4,600 bears studied for almost fifty years in that region.

The female bear was first captured as she came out from her maternity den this spring. At the time, she had a single offspring, which scientists marked for study.

In the autumn, she was spotted once more, but this time with two cubs - the original cub and another without a tag. Researchers aren't sure what happened to the new cub's birth mother, but they are trying to locate her using DNA analysis.

"The bears need every advantage they can get in the current era with a warming climate," noted a polar bear scientist. "When mother bears have the chance to take in another cub and care for it and see it to independence, it's a positive development for the bears."

Polar bears in the wild only have a 50% chance of surviving into maturity, but having a mother caring for them improves their odds.

The young bears appear to be healthy, researchers said, and they will likely stay with their adoptive mother until they are about 30 months of age.

Next, the bear family is expected to head out to the frozen ocean, where the cubs will learn from their mother how to hunt seals and live on their own.

"It's just nice to know that the animals are caring for each other," concluded the researcher.