(CN) — Touting the cub’s “bearish female power,” the Tierpark zoo in Berlin, Germany, said Friday it was finally able to perform a medical checkup that determined the sex of a baby born in December to Tonja the polar bear.
Still unnamed, Tonja’s 11-week-old cub is "a perky, strong girl,” weighing 18.7 pounds and stretching 24 inches from head to tail.
Tonja and her cub are not out of the woods yet, so to speak: the zoo warns that polar bears have an “extremely high” infant mortality rate.
Roughly 85 percent of polar bears in the wild do not live past their second birthday, and both of Tonja's last two cubs died within months of birth.
Tonja herself is 9 and mated with 7-year-old Wolodja several times in March and April 2018.
Noting that polar bears are solitary animals, and that males in the wild are not involved in raising the young, Wolodja was moved back to the zoo over the summer to ensure a peaceful pregnancy for Tonja.
No one approached the birthing den for months after the cub’s birth on Dec. 1, 2018, to ensure a healthy atmosphere, but zookeepers using a video feed saw the cub first open her eyes at around 5 weeks.
“The camera shows us that the cub is becoming more active every day,” curator Florian Sicks said at the time. “It is already trying to crawl and get up on its feet.”
Tonja will likely return to the zoo in the coming months.
“In zoos just as in the wild, mothers and their cubs do not leave their dens until the spring,” the zoo reports.
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