APES - Pongidae
Hylobates concolor leucogenys
In Vietnam this gibbon is found in Lai Chau, Son La, Hoa Binh and Nghe An. In the world they are only found in Lao.
They live in mountainous forest and woods on limestone forest.
Gibbons have the longest arms of all the primates and with these arms they can move more than three meters with one armswing. The males are black with white cheekes, but all the baby-gibbons are born yellow like the females of this species. After some time the male newborn wil turn black. Gibbons always live in family groups and only during the breeding season there might be some interaction with other family groups. The gibbon is active during the day and you will seldom see them on the ground.
They reach their sexual maturity at an age of 8 to 9 years. The female always give birth to one young after a gestation period of 200 to 214 days. She will give birth once a year or twice in three years.
In Hanoi Zoo there is one family group. Father, mother and their two children. One of them is a male born in August 1998 and already turned black, the youngest one is a female born in September 2000 and she will stay yellow just like her mother.
Gibbons are endangered. Its numers have declined drastically in the last years due to habitat loss to agriculture and overhunting for the wildlife trade. As a result of this there are hardly no more gibbons living in the wild.