General information from Koko.org
first recorded gorilla sighting (by western civilization) was in the 5th
century B.C. by a Roman explorer.
are three subspecies of gorillas living in different parts of Africa. The
differences between them are very slight.
Lowland Gorilla (gorilla gorilla)
Lowland Gorilla (gorilla graueri)
Gorilla (gorilla berengei)
|Western -||Approximately 10,000-35,000 free-living, 550 in captivity worldwide. Found in Nigeria, Cameroon, Gabon, Congo, Central African Republic and Zaire.|
|Eastern -||Approximately 4,000 free-living. Less than 24 in captivity. Found in eastern Zaire.|
|Mountain -||Approximately 620 free-living. Zero in captivity. Found in 285 square miles in the rain forests of Rwanda, Uganda and Zaire.|
|Height:||Males 5'6" upright, 4'6" normal stance. Females 5' upright, 3'6" - 4' normal stance.|
|Weight:||Males 300-500 lbs. Females 150-250 lbs. Babies fromone to three years weigh between 20-30 lbs.|
|Arm Span:||Up to 9'2'' (one male specimen).|
or brown-gray fur with black skin on chests, palms and faces. Red heads
|Stance:||Gorillas are quadrupedal. They walk on all fours with the soles of their feet flat on the ground and the knuckles of the hands curled and planted on the ground.|
Gorillas recognize each other by their faces and body shapes. Each gorilla has a unique nose print.
differences between mountain gorillas and lowland gorillas are slight and result
mainly from adaptation to high altitudes. Mountain gorillas have longer body
hair, higher foreheads, longer palates, larger nostrils, broader chests, shorter
arms, shorter, wider hands and feet.
is 8-1/2 months. There are typically 3-4 years between births. Infants stay with
their mothers for 3-4 years. Females mature at 10-12 years (earlier in
captivity); males 11-13 years, sometimes sooner if they assume leadership early.
Lifespan is between 30-50 years.
eat some 200 types of leaves, tubers, flowers, fruit, fungus and some insects.
Favorite foods include bamboo, thistles and wild celery. Gorillas do not drink
water. They obtain all the moisture they need from the vast amounts of foliage
they consume. Males consume approximately 50 lbs. a day.
|10am-2pm||Eat, play, relax, sleep|
|2pm-5pm||Travel 300-6,000 feet - foraging on the way|
live in groups of 3-30. A typical group consists of one silverback, one immature
silverback, one immature male, three to four adult females, and three to six
youngsters under eight years old. A female will usually transfer to another
group, particularly if the silverback is her father and there are no other
suitable males to mate with. Adult males usually leave after sexual maturity and
start their own group or join other "bachelors."
learn from their mothers and other adults what to eat, social and sexual
behavior and how to rear young. They care for their babies with great affection,
patience and playfulness. Energetic, mischevious youngsters are disciplined with
stern vocalizations (pig-like grunts), body posturing and strong looks. Gorillas
also chuckle, smile and purr. They are gentle and intelligent. Gorillas feel
deeply and remember for years. Groups are not territorial and generally avoid
each other, but when they do meet, sometimes threats and fighting occur, with
the silverback remaining to challenge the attacker while the rest of the group
flees. To intimidate his opponent, the silverback stands upright to appear
larger, beats on his chest, roars, waves his arms, tears branches and charges.
This is all done to frighten off, not harm, other males. Distress behavior
includes diarrhea and strong, pungent body odor.
is gorilla's only enemy. Because of the actions of male gorillas protecting
their groups with such determination from hunters, humans developed a folklore
about the ferocity of gorillas. Gorillas' defense of standing and chest-beating
make them a perfect target. Like all tightly knit social groups, gorillas will
defend their young. They defend them with their lives.
Gorillas are generally quiet. They are not physically capable of making the same sounds as humans. They generate about 25 distinct noises, however. Hooting can carry a mile through the forest and is usually exchanged between rival silverbacks. Other vocalizations include screams, grunts (indicating contentment) and high-pitched barks (indicating curiosity).
hour visit in Africa with gorillas costs about $120, with a maximum of six
tourists visiting each habituated gorilla group a day. It can take several hours
to reach the gorillas through the dense, mountainous jungle. Safaris start at
$3,000. Tourism generates a great deal of money for Rwanda, Uganda and Zaire and
helps protect other species as well as the gorilla.
countries have passed laws protecting the gorillas, but enforcement is difficult
in remote jungles where the people exist by hunting. Most zoos around the world
have agreed not to purchase gorillas from the wild and participate in a
worldwide captive breeding program designed to expand the existing captive
population while maintaining a viable gene pool.
greatest threat to the long-term survival of gorillas is habitat encroachment.
The human population explosion in Africa continues to create a need for more
land to grow food and house people. Gorillas have no place else to go. They can
adapt to no new way of life. Tourism has contributed greatly to saving gorillas,
but the future is not at all certain.
B. Schaller & Nan Richardson. Gorilla: Struggle for Survival in the Virungas.
Board of Victoria, Education Service. Gorilla Gorilla Gorilla: All about
Other Rainforest Animals. 1990.
Godwin. Gorillas. 1990.
Bailey. Gorilla. Save our Species Series) 1990.
Talk. Pittsburgh Zoo, Fall 1986.
6.Boyd Norton. The Mountain Gorilla. 1990.