BERLIN — Berlin’s Tierpark zoo is celebrating the birth of a polar bear, nine months after its mother lost a cub.

Footage posted on social media shows mother Tonja tenderly licking the unnamed cub shortly after its birth Thursday. A second cub was stillborn.

The zoo, in the eastern part of the German capital, said Friday that the new polar bear is about the size of a guinea pig and has already been heard suckling.

Tonja’s first cub, Fritz, died of unknown causes in March at the age of four months.

The mortality rate for young polar bears is about 50 percent and can be even higher during the first 10 days.