| FACT FILE: |
| Swahili
Name: |
Gorila or N'gagi |
| Scientific
Name: |
Gorilla gorilla beringei |
| Size: |
Up to 6 feet tall |
| Weight: |
300 to 425 pounds |
| Lifespan: |
53 years in captivity |
| Habitat: |
Dense forest, rain forest |
| Diet: |
Vegetarian |
| Gestation: |
Vegetarian |
| Predators: |
Leopards, crocodiles, humans |
|
Few animals have sparked the imagination of man as much
as the gorilla, the largest of the living primates and the
last member of the ape family known to science. Most gorillas
live in inaccessible regions in various dense forests in
tropical Africa, and only in the last 30 years have scientists
learned details of their life in the wild.
A chain of eight volcanoes known as the Virunga Volcanoes runs
through a western section of the Rift Valley, forming part of
the border between Uganda, Democratic Republic of Congo (formerly
Zaire) and Rwanda. These spectacular mountains and the nearby
Bwindi Impenetrable National Park in Uganda are the last
refuges of the most endangered of the gorilla subspecies, the
mountain gorilla. Only about 630 of these individuals remain.
Physical Characteristics
The gorilla is massive, with a short, thick trunk and broad
chest and shoulders. Its eyes and ears are dwarfed by its
large head and hairless, shiny black muzzle. Older males
develop a crown of muscle and hair that makes the head look
even longer. The arms are longer than the stubby legs. The
fully adult male mountain gorilla is twice as large as the
female.
Habitat
The most serious threat to gorillas is habitat loss. The rich
volcanic soil of the Virungas is as highly valued as farming
land. In Rwanda, Uganda and Congo, a regional conservation
program stressing the importance of maintaining the virgin
forest watershed and the need to habituate some groups of
gorillas for tourist visits has helped ease encroachment.
Behavior
The gorilla is shy and retiring rather than ferocious and
treacherous. It usually seeks no trouble unless harassed but
will valiantly defend its family group if threatened. Family
groups are close-knit and may have up to 30 members, but even
if smaller, the group usually consists of at least one older
male, one or more females and a few juveniles.
Gorillas have strong attachments to members of their own
group and even when groups meet and mingle and then
subsequently part, each animal tends to remain with its
respective unit. An adult male called a silverback named for
the silvery gray hairs on its back normally leads each group,
serving as its chief protector and defender. Gorillas
continually wander through their home ranges of 10 to 15
square miles, feeding and resting throughout the day. Because
gorillas are nomadic, they build new nests each day at dusk,
constructing them of bent branches in a tree or of grasses on
the ground.
A group's hierarchy, ritualized behavior and bluff charges
between males prevents conflict among and between groups.
Gorillas scream, grab foliage and stuff it in their mouths,
stand erect on their hind legs, tear up and throw plants, drum
on the chest with hands or fists, stamp their feet, strike the
ground with the palms of their hands and gallop in a mock
attack on all fours.
Diet
Animals of this size need a lot of food, and the vegetarian
gorilla is no exception. Although they eat a variety of plants,
favorites include wild celery, bamboo, thistles, stinging
nettles, bedstraw and certain fruit. These plants seem to
provide sufficient moisture so that gorillas do not need
water.
Caring for the Young
Mountain gorillas have a slow rate of reproduction. Females
give birth for the first time at about age 10 and will have
more offspring every three or four years. A male begins to
breed between 12 and 15 years, when he is in charge of his own
group. Able to conceive for only about three days each month,
the female produces a single young.
Newborn gorillas are weak and tiny, weighing in at about 4
pounds. Their movements are as awkward as those of human
infants, but their development is roughly twice as fast. At 3
or 4 months, the gorilla infant can sit upright and can stand
with support soon after. It suckles regularly for about a year
and is gradually weaned at about 3
1/2 years,
when it becomes more independent.
Predators
The gorilla's only known enemies are leopards and humans.
Crocodiles are potentially dangerous to lowland gorillas. In
western Africa, gorillas are commonly hunted for meat or in
retaliation for crop raiding, but in eastern Africa they have
been the victims of snares and traps set for antelope and
other animals. Poachers have also destroyed entire family
groups in their attempts to capture infant gorillas for zoos,
while others are killed to sell their heads and hands as
trophies.
Did you know?
- Gorillas rarely attack humans. But in an encounter a
person should stay still and refrain from staring or
pointing at the gorilla.
- Gorillas are susceptible to various parasites and
diseases, especially to pneumonia during the long, cold
wet seasons.
