Two polar bear cubs were born Friday night, Nov. 6, at the Columbus Zoo and Aquarium in Powell.

Zoo animal care staff said they observed Aurora, mother of the cubs, caring for the newborns though, despite her efforts, only one cub has survived.

Polar bears have one of the lowest reproductive rates of any mammal. The survival rate for a polar bear cub during the first few weeks of life is only about 50 percent.

At this time the surviving cub is doing well and Aurora is being an attentive mother, zoo officials said. The two are in a private denning area off public view where they will remain until spring.

The Columbus Zoo animal team, in conjunction with recommendations from other polar bear breeding facilities, made the decision not to intervene. Polar bear cubs are difficult to hand rear and disrupting Aurora’s maternal care was not advised.

“We are excited about this birth but we remain cautiously optimistic,” said Carrie Pratt, curator of the zoo’s North America region. “Aurora and her cub appear to be doing well but since polar bear cub survival rate is very low we will continue to monitor the two around-the-clock.”

Female polar bear twins Aurora and Anana arrived at the Columbus Zoo in 2010 when the Polar Frontier region opened. The twins are now 8 years old and both have mated with the 28-year-old male polar bear, Nanuq, who arrived in 2012. All three polar bears came from other zoos on breeding loans as part of the “Species Survival Plan” for the threatened species.

It is unknown if Anana is pregnant; however, her desire to den may indicate it is a good possibility, officials said.

Polar bears are native to the circumpolar north including the United States (Alaska), Canada, Russia, Norway and Denmark (Greenland). They are at the top of the Arctic food chain and primarily eat seals. Polar bear populations are declining due to the disappearance of sea ice, and experts estimate that only 20,000-25,000 polar bears are left in the wild. Some scientists believe if the warming trend continues two-thirds of the polar bear population could disappear by the year 2050, zoo officials said.

“Polar bears need our help,” said Columbus Zoo and Aquarium President and CEO Tom Stalf. “We are committed to doing everything we can at the zoo, as well as supporting conservation initiatives for wild populations, to save these animals for generations to come.”

The Columbus Zoo has been designated an “Arctic Ambassador Center” by Polar Bears International.