The Jungle's Entertainers. Every morning, the jungle is "entertained" by the ear-piercing howls of various gibbon troops. These "duets" are usually between a mated pair. Besides strengthening the couple's bond, these calls also proclaim each group's territory and ward off possible intruders. Family Life. The White-handed Gibbon is monogamous to its mate. They live in small groups comprising the mated pair and their offspring. The offspring stay with the parents until adolescence where upon they are chased out from the group.