The Oregon Zoo in Portland, Oregon, celebrated the birthdays of two polar bears — and they’re half-sisters.
Nora and Amelia Gray turned 7 and 6, respectively, and the Oregon Zoo posted a sweet video to commemorate the day.
Nora and Amelia Gray are half-sister polar bears; both were born at the Columbus Zoo in Ohio.
At just 10 months old, Nora was transferred to the Oregon Zoo to keep a lone polar bear company.
The half-sister polar bears had not met until last year, when Amelia Gray joined the Oregon Zoo where Nora was living.
Although it was their first meeting, the two bears immediately hit it off, zookeepers said.
Amy Cutting, who oversees the Oregon Zoo’s polar bear habitat, said the animals' first meeting began slowly; but the two then seemed to accept each other very well.
"Polar bear introductions can be very intense, so we took it slowly at first," she said.
"But they made it very clear they wanted to be together, and their care team listened."
"Now, the two are having a great time playing and hanging out," she said.
The two half-siblings are seen in the video as young polar bears growing up together — playing on rocks and having fun, in the most recent clips.
The two polar bears are being studied by Polar Bears International and the U.S. Geological Survey at the zoo.
The research explores how climate change is affecting the polar bears and their diets.
The connection between climate change and the impact on polar bears is not new.
In late 2019, the American Geophysical Union released research suggesting that mother polar bears — by the end of this century — may no longer be able to locate the deep snowbanks they need in order to dig dens.
They need this specific habitat in order to give birth.
Christopher Carbone contributed to this report.