Hainan Gibbon

The Hainan gibbons reside in three different types of forests on the island. Their main area of occupancy is known as the primary forest (Old-growth forest). Within the primary forest the gibbons typically live in trees that are ten meters or taller. Along with offering sources of shelter and trees for singing rituals, the primary forests are also home to at least six species of plants eaten by the gibbons. When primary forests are destroyed, it takes the trees an extensive amount of time to regenerate to a state that is suitable as a home for the gibbons. In the 1960s, much of Hainan's lowlands were deforested to make way for rubber plantations and commercial logging, causing a dramatic decline in their population. These actions forced gibbon communities to higher elevations. By 1999, only 4% of the gibbons' original habitat remained on the island. Aside from primary forest, the gibbons split their time between two areas known as secondary forests and dwarf forests. The secondary forests are less suitable for the Hainan gibbons than the primary forests. Their trees are shorter in height, and they severely lack resources, such as food and shelter, needed by the gibbons to survive. The dwarf forest is even less favorable for the gibbons and a study by Fan et al. found that gibbons spent only 0.5% of the 13-month study period in dwarf forests. …

The breeding characteristics for the Hainan gibbon do not lend themselves to rapid population growth. The breeding females have a single offspring every two years and the newborn has a dependence period of roughly a year and a half. Furthermore, there are currently no Hainan gibbons in captivity and all previous attempts to breed them in captivity have failed.