Physical Characteristics
The silvery gibbon is 18 to 25 inches long, weights 12 pounds and has no tail. Its eyebrows, cheeks and beard are are pale and merge with the rest of its hair that is mostly the silvery color the animal gets its common name from. The head of the animal has a dark gray-blue cap of fur. It has long arms and lean bodies for traveling through the treetops.
Behavioral Characteristics
The silvery gibbon lives in pairs. They are male, female breeding pairs. A pair of silvery gibbons is usually accompanied by their young. Most groups have only a young that is nursing and a juvenile still with them. This makes most groups have only 4 members. The group uses calls in order to defend its territory. The calls can be heard up to one kilometer away from the silvery gibbon making the call.
Life Cycle
There is not a specific breeding season for the the silvery gibbon. However, the female usually gives birth to a single young about every 40 months or a little over 3 years. The gestation or pregnancy of the female of this species lasts about 7 months. The young are most likely nursed until about 2 years old, however this information is pure speculation based on similar gibbons since there is limited information available and little research has been done on this species. Females remain able to reproduce for about 10 to 20 years and normally give birth to 5 or 6 young during its life. The lifespan of this species is estimated to be a maximum of 44 years in captivity. Wild individuals tend to live much shorter lives then captive animals.
Diet
The diet of the silvery gibbon consits mostly of fruits and some leaves. It also will eat nectar and grubs occasionally.
Habitat
The silvery gibbon is found in South East Asia on the Indonesian island called Java. It inhabits tropical and semi-evergreen forests.
Conservation Status
The silvery gibbon is classified as endangered on the IUCN (International Union of Conservation of Nature and Natural Resources) red list of threatened species. Its population is less then 2,500 individuals in the wild. Each sub-population has less then 250 members. The number of mature individuals is continuing to decline. Habitat loss is one threat but is not as serious as it used to be. Wildlife trade is a threat but the seriousness of the threat is undetermined at this time.
References:
Animal: The Definitive Visual Guide to the World’s Wildlife by, David Burnie and Don E. Wilson
http://animaldiversity.ummz.umich.edu/site/accounts/information/Hylobates_moloch.html
http://www.iucnredlist.org/details/10550/0
