BERLIN (AP) — Berlin's Tierpark zoo says its latest baby polar bear is "a perky, strong girl."

Keepers and vets were able to separate the 11-week old bear from mother Tonja for the first time to conduct a medical checkup, during which they also determined the cub's sex.

The zoo said Friday that the as yet unnamed bear weighs 8.5 kilograms (18.7 pounds) and is 61 centimeters (24 inches) from head to tail.

Tonja's last two cubs died within months of birth and keepers caution that the mortality rate for young polar bears can be quite high.