Silvery Gibbon
Encyclopedia
The silvery gibbon is a primate
in the Hylobatidae or gibbon
family. Its coat is bluish-grey in colour, with a dark grey or black cap. Like all gibbons, Silvery Gibbons lack external tails, have dorsally-placed scapula and reduced flexibility in the lumbar region. They have long, curved fingers and very long forelimbs relative to their hind limbs. On average, they reach 8 kg in weight.
The silvery gibbon lives exclusively on the island of Java (Indonesia
), where it inhabits deeply hidden portions of the rain forests. It is diurnal
and arboreal, climbing trees skilfully and brachiating
through the forests. Brachiation is aided by the possession of mobile wrist joints, full rotation of the upper arm and the ability to lock elbows in suspension. Its diet consists of fruits, leaves, and flowers.
Every three years, on average, the female births a single young, after a seven month gestation. The offspring is nursed for about 18 months and lives with the family group until it is fully mature at about 8 years.
Several zoos operate silvery gibbon breeding programs. Despite these efforts, the future survival of this species is in question.
Like all gibbon species, the silvery gibbon lives in pairs and stakes out territory that the pair strongly defends; it has relatively small territories of about 42 acres. Females sing to declare their territory several times a day, and if strangers are spotted the male screams loudly in an attempt to scare them away.The males are usually very aggressive to others.:)
These subspecies are not recognized by the IUCN Red List.
Primate
A primate is a mammal of the order Primates , which contains prosimians and simians. Primates arose from ancestors that lived in the trees of tropical forests; many primate characteristics represent adaptations to life in this challenging three-dimensional environment...
in the Hylobatidae or gibbon
Gibbon
Gibbons are apes in the family Hylobatidae . The family is divided into four genera based on their diploid chromosome number: Hylobates , Hoolock , Nomascus , and Symphalangus . The extinct Bunopithecus sericus is a gibbon or gibbon-like ape which, until recently, was thought to be closely related...
family. Its coat is bluish-grey in colour, with a dark grey or black cap. Like all gibbons, Silvery Gibbons lack external tails, have dorsally-placed scapula and reduced flexibility in the lumbar region. They have long, curved fingers and very long forelimbs relative to their hind limbs. On average, they reach 8 kg in weight.
The silvery gibbon lives exclusively on the island of Java (Indonesia
Indonesia
Indonesia , officially the Republic of Indonesia , is a country in Southeast Asia and Oceania. Indonesia is an archipelago comprising approximately 13,000 islands. It has 33 provinces with over 238 million people, and is the world's fourth most populous country. Indonesia is a republic, with an...
), where it inhabits deeply hidden portions of the rain forests. It is diurnal
Diurnal animal
Diurnality is a plant or animal behavior characterized by activity during the day and sleeping at night.-In animals:Animals that are not diurnal might be nocturnal or crepuscular . Many animal species are diurnal, including many mammals, insects, reptiles and birds...
and arboreal, climbing trees skilfully and brachiating
Brachiation
Brachiation is a form of arboreal locomotion in which primates swing from tree limb to tree limb using only their arms.- Brachiators :...
through the forests. Brachiation is aided by the possession of mobile wrist joints, full rotation of the upper arm and the ability to lock elbows in suspension. Its diet consists of fruits, leaves, and flowers.
Every three years, on average, the female births a single young, after a seven month gestation. The offspring is nursed for about 18 months and lives with the family group until it is fully mature at about 8 years.
Threats and conservation
The silvery gibbon ranks among the most threatened primates. It is listed as Endangered on the 2009 IUCN Red List of Threatened Species,, with the population appearing more stable than in a 2004 assessment of the species being Critically Endangered, which suggested there was a 50% chance of the silvery gibbon becoming extinct within the next decade. Habitat destruction on densely populated Java continues to reduce the natural range of the species. Many gibbons are also lost to the illegal pet trade, when adult gibbons are slaughtered so that their babies can be sold in the markets as pets. There are less than 2,000 silvery gibbons in the wild considered to be genetically viable for the continuation of the species. There are also a dozen small non-viable populations. Aside from these wild populations many silvery gibbons are held as pets throughout Indonesia. Gunung Halimun National Park, is able to sustain a population of 1000 gibbons.Several zoos operate silvery gibbon breeding programs. Despite these efforts, the future survival of this species is in question.
Like all gibbon species, the silvery gibbon lives in pairs and stakes out territory that the pair strongly defends; it has relatively small territories of about 42 acres. Females sing to declare their territory several times a day, and if strangers are spotted the male screams loudly in an attempt to scare them away.The males are usually very aggressive to others.:)
Classification
Some experts recognize two subspecies of the silvery gibbon:- Western silvery gibbon or Western Javan gibbon, Hylobates moloch moloch
- Eastern silvery gibbon or Central Javan gibbon, Hylobates moloch pongoalsoni
These subspecies are not recognized by the IUCN Red List.
External links
- ARKive - images and movies of the Javan gibbon (Hylobates moloch)
- http://www.gibbons.de