There are only around 150-160 white-cheeked gibbons left in the wild, as well as about 200 in captivity, Wroclaw zoo said. In the wild, the animals are found in Vietnam and Laos. They have also been seen in China, although not for 30 years.
White-cheeked gibbons are difficult to breed. Dao was born in late September, but the zoo only announced his birth on Thursday.
According to Radoslaw Ratajszczak, the head of Wroclaw Zoo, it has one of the best enclosures for gibbons in Europe, mimicking their natural habitat with lots of trees and ropes.
"They can behave naturally here and have peace and quiet. They return the favour with beautiful songs and offspring," said Ratajszczak.