White-handed gibbon
There are variety of primates that is breed and kept in Wildlife Fauna Janda Baik. Here is only some of them.
The White-handed gibbon, like the gorilla, chimpanzee and
orangutan, is an ape, not a monkey. They share with the great apes (gorilla,
orangutan and chimpanzees) several features: a large brain, a flat face with
shortened jaws, a more or less upright posture, a broad chest and no tail.
Ischial callosities are present.
Gibbons are very small and lightweight. They have a small, round head, very long
arms (the arms are longer than the legs), and a short, slender body. Gibbons
have lightweight bones. The long forearms which assist it in suspensory
behavior. Gibbons are arboreal; they spend most of their lives in trees.
Gibbons are covered with light-colored to very dark brown ( or black) dense hair
on most of their body (except their face, fingers, palms, armpits, and bottoms
of their feet). Fur is extremely dense, providing protection from rain. One
square centimeter of skin has over 2,000 individual hairs (13,125 per sq. in.)
compared to 900 hairs per sq. cm. for Old World monkeys.
Some species of gibbons have a white face ring, a band of white face completely
surrounding their jet-black face.Snout is not protruding; nostrils are more
widely spaced and more lateral than Old World Monkeys. Small jaws with long
canine teeth.
Gibbons have senses very similar to ours, including hearing, sight (including
color vision), smell, taste, and touch.
Gibbons' hands are very much like ours; they have four long fingers plus a
smaller opposable thumb. Their feet have five toes, including an opposable big
toe. Gibbons can grasp and carry things with both their hands and their feet.
When they swing through the trees (called brachiating), they use four fingers of
their hands like a hook (but they do not use the thumb for this). Thumb is used
for climbing tree trunks and thick branches and for manipulation of food and
grooming. The upper sides of hand and feet are always white ('white-handed'),
contrast is less apparent in the buff specimens.
The average body mass for an adult male white-handed gibbon is around 5.7
kilograms, and for the female it is around 5.3 kilograms. Male gibbons are
slightly larger than the females. Males are about 3 ft (90 cm) long and weigh
about 15 pounds (7 kg).
The white handed gibbon has throat sac located beneath the chin to help enhance
the calls. Male song is simple with quaver-hoots, female song is longer, rising
to climax, about 18 seconds long.
Location:
The white-handed gibbon is found in different parts of southeast Asia, the
countries of Burma, China, Indonesia, Malaysia, North Sumatra, and Thailand.
This species is found in old growth tropical rain forests, semideciduous monsoon
forests and tropical evergreen forests. They prefer the covered closed canopy
but during feeding may climb to highest emergent crowns of trees or descend to
clumps of bamboo and low bushes, or to drink.
Food:
The lar gibbon is one of the pickiest eaters in the primate world. The
white-handed gibbons are mainly frugivores, preferring fruits high in sugar such
as figs. Gibbons are omnivores (eating plants and meat). They forage for food in
the forests during the day, eating fruit, and they may visit 16 or more widely
spaced food trees in a day's foraging. About 75% of their diet is fruit, but
they also eat leaves, flowers, seeds, tree bark, and tender plant shoots.
Sometimes they also eat insects, spiders, snails, bird eggs, and small birds.
Zoo diet is primate chow, fruits, vegetables and browse.
Gibbons drink water, often by dipping a furry hand into the water or rubbing a
hand on wet leaves, and then slurping up the water from their fur. Gibbons
sometimes do this while dangling above the water from a thin tree branch. They
drink by licking their own fur after a storm, or dipping an arm into a tree hole
or rubbing it on wet foliage.
They have several adaptations for feeding. One of them is brachiating
locomotion, which involves swinging from branch to branch by their arms. This
style of motion allows them to reach the edge of the tree canopy, where most of
their food is found. Other adaptations include high cusps on their back teeth to
help grind plant matter, and a gut adapted for a folivorous diet.
Social:
Gibbons are social animals that are active during the day (they are diurnal).
Gibbons mate for life; the young, born singly, remain with the family group
until they are five or six years old. Like other apes, gibbons groom one another
(they clean the hair of a family member).
The males are not socially or physically dominant over females. They are
vigorously territorial, spending up to 1/2 hour or more each morning calling and
displaying. The function of calling seems to be both territorial and to
reinforce the pair bond. The calling bout is usually initiated by the female.
Male and female "duet" with different "songs." The female song is a plaintive
swooping call, rising to a crescendo - her great call; the male calls with a
high-pitched "quaver song."
The male usually takes the lead in attacking other gibbons encountered, although
they rarely actual fight. Playful 'biting' matches, which can be painful to a
human, seem to determine rank order of mature juveniles within the group. Even
serious bites don't seem to hurt them because of their dense fur.
Female gibbons carefully nurture their young. Eyes are open at birth and body
and limbs are bare; very dependent on their mother for warmth. Many are white at
birth and do not become black or final color until 2 – 4 years old. Babies can
grasp their mother's fur to cling to the mother's belly soon after birth.
Infants are hairless except for a cap of fur on the crown. Babies usually have
light hair at first and darker hair develops as they grow older. They are weaned
at about 1 year old. Young gibbons stay with their mother for about 6 years. The
young then venture out (or are forced out) to start a new family group of their
own.
Movement:
Gibbons are extremely acrobatic and agile. They spend most of their life in the
trees. They move by swinging gracefully from branches and vines; this is called
brachiating. When they brachiate, they use four fingers of their hands like a
hook (but not the thumb). They swing from branch to branch (horizontally or
vertically), with legs flexed under body; using arms alternately and keeping
hand bent in hook shape, and movements appear effortless. They are able to
change direction even during fastest bounding by slightly touching a branch.
While swinging, they are able to catch birds out of the air and eat them after
landing.
They can also walk along small branches high up in the air, like tightrope
walkers; they use outstretched arms to help keep their balance. Gibbons climb
when moving slowly and feeding. Gibbons can also leap acrobatically across large
gaps in the tree canopy from tree branch to tree branch; gibbons have been known
to leap over 30 feet (9 m) in a single jump. The gibbon is the only anthropoid
ape to walk on its hind limbs only, usually raising its arms for balance.
Gibbons cannot swim and avoid the water. When on the ground (which is rare),
gibbons walk bipedally (on two legs).
These are the most active of all gibbons. They move faster, more quietly, and
farther each day than any other forest apes or monkeys. Brachiation comprises
90% of locomotor activity. Adaptations include precision of movement, incredible
eye-hand coordination and dexterity. This remarkable agility makes a healthy
adult gibbon virtually invulnerable to predation. They sleep sitting on their
ischial callosities, hands resting upon flexed knees and head buried between
knees and chest.
Territories:
Each family defends its territory by song and threat display. Gibbons are very
territorial. A pair maintains and defends a territory through a series of calls
and vocalizations. They also use an elaborate system of calls to keep track of
family members within the territory.
Communication:
The white-handed gibbon is distinguished by its musical howl. They are quiet
during the day but commonly howl at sunrise and sunset. They are very vocal,
making loud "whoop" sounds. Their loud resonant songs can be heard up to 1/2
mile away. Songs by far excel those of all other species because of a
sound-amplifying throat sac.
Duetting is the singing between the male and female, and is dominated by the
female. This helps to maintain the pair bond between the pair and to maintain
the territory. Each morning upon awakening a family group of gibbons loudly
announces its presence in the forest, using a territorial hooting call and
menacing gestures. This call warns other gibbons to stay out of their territory
(and especially away from the local fruit trees). This noisy display takes 1/2
hour or more every morning and is usually started by the adult female. The male
and female have different calls.
In friendly greetings, corners of mouth are drawn back, revealing teeth, and
tongue is sometimes protruding. In anger, mouth is opened and closed repeatedly,
smacking lips and snapping teeth together. Snarling is interpreted as an
intention of biting.
There are 9 species with 9 different territorial songs. The gibbons seem to be
born knowing the songs because they are always the same, and not learned.
Habits:
Gibbons do social grooming, when one individual grooms another, to reinforce the
bonds between individuals.
They do not construct sleeping nests but show preference for specific 'sleeping
trees' where no other
family group is tolerated. They sleep sitting erect in trees, huddled together
in twos and threes, with knees bent up to chin, hands folded on knees and face
buried between the knees and chest. They sleep sitting upright, resting on tough
pads located on their rear ends (these pads are called ischial callosities).
Status: endangered
This species is threatened for a several reasons. These gibbons are hunted for
meat in some areas. Live capture for the pet trade also poses a serious problem.
In many Asian countries, it is "fashionable" to own your own primate, and this
has led to the death of many gibbons either at the time of capture or during
transport. The final, and greatest, threat to the gibbon is deforestation.
Rainforests are disappearing at an alarming rate due to logging and
agricultural, leaving forest species with an ever smaller region in which to
live. Some efforts are being made to save these primates, such as national parks
and reserves, but they are not very effective. Laws protect them from live
capture, but they are rarely enforced.
Gibbon populations are decreasing; they are threatened with extinction. There
are estimated to be about 79,000 lar gibbons (the white-handed or common
gibbon). Lar gibbons retain only 10% of their original habitat in protected
reserves. In 1987, the IUCN estimated that there were 79,000 lar gibbons but to
protect the more endangered species, all are listed as endangered by the USDI
(1980) and are on appendix 1 of the CITES, prohibiting commercial trade in
gibbons. They are endangered and participate in the Species Survival Plan.
Life span is 30 to 40 years.