orangutan is Asia's great red ape, and is an endangered species.
In the wild, it can only be found on the islands of Northern
Sumatra and Borneo, in lowland tropical rainforest areas with
complex canopy structures. There are two subspecies of orangutan,
the Bornean (Pongo pygmaeus pygmaeus) and Sumatran (P.p. abelii),
which are slightly different from one another. The Bornean subspecies
is usually darker and the cheek pads are larger than the Sumatran
word orangutan is Malay meaning "Man of the Woods";
appropriate, as it is the only truly arboreal (tree dwelling)
ape. Its very long arms and hook-shaped hands and feet are adaptations
to its arboreal lifestyle. Nests are built in forest canopies
at night, for sleeping, made from interwoven branches and leaves.
Adult males grow to about five feet and weigh an average of
120kg, while adult females only grow to about four feet and
bulk of an orangutan's diet is fruit, but they also eat bark,
leaves, shoots, buds and stems. They have also been known to
eat insects such as termites, mineral rich soil, honey and even
to steal eggs from nests in the trees.
are not sociable like their relatives, the chimpanzee and gorilla.
The males wander alone and females are accompanied by their
infants or sometimes an older juvenile. This is largely because
favoured fruits are usually widely dispersed and can't support
large groups. Orangutans, however, are sociable during the high
fruiting seasons in the rain forests and thus their movements
are very dependant on the presence of ripe fruit. A distinct
pecking order exists in times of high fruit production, both
in males and females. There may be a high degree of territorial
overlap and as many as six males may range independently over
a given area at the same time.
males have cheek flanges which enlarge their face during aggressive
displays with other males. These encounters are used to establish
male hierarchies and if contact is made, can sometimes be deadly.
But this occurs infrequently, and orangutans prefer to avoid
confrontation, and call to advertise their presence. Only the
male vocalises using his throat pouch which inflates during
calling. This adds resonance to the territorial 'long call',
which is a series of loud roars which rises to a crescendo before
dying back to low groans, and is usually accompanied by branch-breaking.
The exact reason for this call is unknown, but it is thought
that it serves the function of attracting receptive females
as well as letting other males know of each other's whereabouts.
Adult males reach sexual maturity between 8 and 15 years and
will develop cheekpads and throat pouch as late as 20 years.
female reaches sexual maturity at 9 to 12 years old, and can
be expected to give birth to three to four offspring in her
lifetime (once every eight years on average). Each pregnancy
lasts 260-270 days, and a mother rears her infant on her own.
Very rarely are twins born. The infant is not fully weaned until
it is three years old, and will remain with its mother until
she gives birth to another. This means that mother and young
may stay together for up to 6 years. Young orangutan are more
sociable than adults and often gather together to play. Although
a sexually mature male may roam to find receptive females, orangutans
usually only travel a few hundred metres through the trees each
day. Orangutans can be expected to live between 35 to 50 years
in the wild.
thousand years ago, orangutans ranged as far as north China
and far south into the Indonesian island of Java. Best known
estimates today suggest that only about 22,000 and 5,000 remain
on Borneo and Sumatran islands respectively. It is estimated
that in the last 10 years the orangutan population has halved.
greatest threat to the orangutan population is the destruction
of its lowland rainforest habitat for conversion to plantations
and agriculture, and logging for timber. Fire and logging
leaves isolated patches of forest which prevents interbreeding
between populations. Rainforest clearing exposes the orangutans
to hunting for meat and enables the kidnapping of juveniles.
infants are dependent on their mothers for about seven to
eight years old, the mother is often clubbed or shot to death
to capture the infants. The largest market for kidnapped orangutans
is private pet owners. Trade to zoos, laboratories and the
entertainment business, however, also play a part.
orangutan has been given protected status for over half a century;
it is illegal in Indonesia and Malaysia to kill, own or sell
an orangutan. Orangutan infants, however, are still confiscated
from private citizens by Indonesia's wildlife and law enforcement
authorities. It is estimated that for every orangutan sold by
a dealer outside Indonesia, three to four orangutans have died
as part of the cruel and inhumane process involving poaching,
transportation and maintenance of infant orangutans in the 'black'
only way to secure the future of the Orangutan is to protect
as much of its rainforest habitat as possible, in the form of
establishing reserves, while strictly enforcing the laws against
capturing and owning an orangutan. Obtaining local and international
support through public awareness, education and tourism will
also help the orangutan to survive.
- A new Orangutan project is under consideration. Please
stop back for more details.