A giant panda surprised zookeepers at Vienna’s Schoenbrunn zoo after it was revealed she had given birth to an extra cub.
The zoo had originally announced the birth of just one cub on Aug. 7. On Monday zoo officials said the panda mother, Yang-Yang, actually bore twins.
The fact that it took a while to discover the second cub is not surprising. The birth was observed by camera only, and newborn pandas are tiny.
In announcing the first cub’s arrival, the zoo said the latest addition was just four inches long and weighed 3.5 ounces.
The zoo later said that no other European zoo had managed to breed giant pandas by natural means.
Yang-Yang has given birth three previous times. These cubs are her fourth and fifth offspring.