Scientists in Canada have spotted a rare case of a female polar bear adopting a new cub. Polar Bears International, a conservation group, said the female had one cub when tagged in spring. But last month, she was seen with two cubs of similar age. This shows a rare adoption in wild polar bears. "Female polar bears are really good moms and so they’re just primed for looking after and caring for their offspring," explained Evan Richardson, a research scientist. He added, "We think if there’s a little cub that’s bawling on the coast and has lost its mother, these females just can’t help themselves but to take them on and look after them." The bear, known as X33991, and the cubs belong to the Western Hudson Bay group, a well-studied polar bear population. Out of 4,600 bears tracked for nearly 50 years, this is only the 13th adoption seen. Alysa McCall from Polar Bears International said, "Polar bear adoptions are very rare and unusual and we don’t know why they happen." The two cubs appear healthy and are about 10 or 11 months old. They will stay with their foster mother for around 1.5 years, learning how to hunt seals and survive the harsh Arctic environment. The bears are already on the sea ice, according to GPS data. Normally, half of all cubs do not survive to adulthood. Having a mother now greatly improves the adopted cub's survival chances. However, only three of the 13 adopted cubs observed over 45 years survived. Researchers will study genetic samples to see if the biological mother is still alive. In some past cases, cubs were swapped rather than orphaned. McCall commented, "When we confirmed this was an adoption, I had a lot of mixed feelings. But it’s just another reason why this species is so incredible and why they’re so fascinating and interesting. It gives you a lot of hope when you realize that maybe, polar bears are looking out for each other."