LEARN MORE ABOUT GORILLAS

AN ENDANGERED SPECIES
The western lowland gorilla is the most widespread of the gorillas although nobody knows how many currently survive in the wild. The common figure quoted is between 90,000 and 110,000 but it is thought that this could be an exaggeration due partly to previous surveys taking population estimates from protected areas with relatively high gorilla densities, and extrapolating these figures over the rest of the region. No surveys have been carried out recently, but evidence suggests that increased hunting has reduced populations. In contrast, the other subspecies of Western gorilla, the Cross River Gorilla, found on the Nigeria-Cameroon border, has a remaining population which may be as little as 150 to 200.

The mountain gorilla only became known to science just over 100 years ago and since then it has been affected by wars, poaching, disease, and destruction of habitat which meant that by 1989 there were only about 620 remaining. Massive conservation efforts brought about an increase to an estimated 674 individuals by October 2002. The latest Virunga gorilla census conducted between September and October 2003, combined with the 2002 Bwindi census results which established this population at approximately 320, indicates that the world population of mountain gorillas is now at least 700. Since the completion of the Virunga Census at least two additional mountain gorilla births have been documented.

The main threats to the gorilla population are the destruction of their forest habitat, through clearance for agricultural and logging purposes and the trade in bushmeat. The demand for gorilla meat has increased from both road labourers and a growing urban market where it is viewed as a symbol of wealth and prestige. Since male gorillas will actively defend their females and offspring when threatened, their chance of being killed by a hunter is increased and following the death of the silverback, a gorilla group is disrupted and will often split up.

Until recently it was considered that there was only one species of gorilla (Gorilla gorilla), divided into three subspecies that live in different parts of Africa, the Western Lowland Gorilla (Gorilla gorilla gorilla), the Eastern Lowland Gorilla (Gorilla gorilla graueri) and the Mountain Gorilla (Gorilla gorilla beringei). However, recent DNA evidence has led to the recognition of the eastern and western populations as separate full species classified as Gorilla beringei and Gorilla gorilla respectively. The two mountain populations, one in the Virunga Volcanoes area on the border between the Democratic Republic of Congo and Rwanda and the other in the Bwindi National Park in Uganda, belong to the Eastern group which changes their classification to Gorilla beringei beringei.

After chimpanzees, gorillas are our closest relatives and share about 97.7% of our DNA. Mountain gorillas are the largest living primates, an adult male weighing up to 180 kilograms (400 pounds), with an arm span of about two metres (seven feet).They have longer, thicker fur than Lowland gorillas and a slightly different nose shape among other skeletal differences.

A GORILLA´S HABITAT AND DIET
All gorillas are vegetarian except that occasionally they eat ants or termites when they come across a nest or mound in the forest. The very different habitats of the Mountain gorilla and Western gorilla result in differences in their physical appearance, feeding behaviour and diet.

The Mountain gorillas living among the peaks of the Virunga Volcanoes where the vegetation is poor quality, predominantly herbs such as nettles, thistles and celery and vines, with few big trees and almost no fruit, eat the leaves, stems, roots and pith of these plants. They are known as folivores. Also, between June and November, bamboo shoots can make up 90% of the Mountain gorilla's diet. This diet influences the movement of Mountain gorillas which usually only travel about half a kilometre each day, as they are surrounded by their food on the forest floor.

Gorillas living in lowland tropical forests where a large diversity of trees and dozens of types of fruit exist have a much richer diet. Western lowland gorillas eat large quantities of fruit and are known as frugivores. These gorillas are agile climbers to allow them to reach the fruit, and so Western gorillas are lighter-bodied with longer, slender limbs than Mountain gorillas. They travel between one and four kilometres each day moving from one fruit tree to another searching for food which partly explains why Western gorillas are more difficult to track and study.

The gorilla rarely drinks, getting most of the water it needs from its diet, together with morning dew on the leaves. When it does drink, a gorilla soaks the fur on the back of its hand and sucks the water from it.

THE LIFESTYLE OF A GORILLA
Gorillas live in family groups of 2 to 20 for Western gorillas but larger groups, up to 35 for Eastern gorillas (including Mountain gorillas), consisting of a single mature male and several females with their young. Other males usually wander alone, sometimes joining a group for a while. They have no defended territory and groups of gorillas which live within the same area co-exist peacefully, sometimes mingling for a while or simply ignoring one another. Aggression in gorillas is extremely rare and serious fights occur only when a group leader meets another group leader.

They are very social animals and communication between them is important involving a variety of grunts, howls, hoots and barks. There are nearly twenty different vocalisations, each having a different meaning. Gorillas also communicate by beating on their chests, or on the ground. For the silverback male (so called because they develop light grey hair on their back at about 11-13 years of age), chestbeating is a show of power, designed to intimidate. They are also very intelligent and show a full range of emotions including love, hate, grief, fear, joy, pride, shame and jealousy and even laughter.

Gorillas may live for thirty-five to forty years, reaching sexual maturity between the ages of eight and eleven. Females begin breeding at about 10 years of age, but males do not breed until they are at least 15 years old since he usually leaves his parental group when his "silver back" begins developing at twelve or thirteen, to wander alone, or with other males, for a few years before managing to attract females from other groups to join him, thus forming his own family. The gestation period is about 8.5 months, and usually only a single young is born weighing 1.8-3.2 kg, about half the normal weight of a human baby. However, the baby gorilla develops twice as fast as its human counterpart crawling at about nine weeks and walking from 30-40 weeks. Females successfully produce offspring which survive to maturity only once every four to eight years, since 40-60% of gorillas die in their first year of life.

Bwindi NP (331 sq km)

A magnificent verdant swathe across the steep ridges of the Albertine Rift Valley, this ancient rainforest - one of the few in Africa to have flourished throughout the last Ice Age - is home to roughly half of the world's mountain gorillas. Looking deep into the expressive brown eyes of these gentle giants is surely the most exciting and poignant wildlife encounter that Africa has to offer - but we should not let it distract from Bwindi's broader biodiversity, a result of its immense antiquity and an altitude span from 1,160 to 2,607m. The national park has 90 mammal species, including 11 primates, of which the black-and-white colobus, with its lovely flowing white tail, is prominent. The forest birding ranks with the best in Uganda, with 23 highly localised Albertine Rift endemics present.

Getting There
Bwindi can be reached from QENP in the north (2-3 hours), from Kabale to the south (1-2 hours), or from Kampala via Mbarara (6-8 hours). The roads meet at Butogota, 17km from the Buhoma entrance gate. 4x4 recommended during the rains.

What to Do
Gorilla tracking is the main attraction; permits must pre-booked at the UWA office in Kampala. Other guided forest walks are available: one popular trail leads to a pretty waterfall, others focus on birding and monkey-viewing.

When to Visit
Any time, though conditions are more challenging during the rainy season.

Where to Stay
Two up-market tented camps, a lodge, community-run budget rooms and camping are available near the Buhoma entrance gate.

ELGON NP (1,145 sq km)
Elgon is a 4,321m high extinct volcano which in prehistoric times stood taller than Kilimanjaro does today. Although the mountain straddles the Kenya border, its loftiest peak, Wagagai, lies within Uganda and is best ascended from the Uganda side.

Elgon is an important watershed, and its slopes support a rich variety of altitudinal vegetation zones ranging from montane forest to high open moorland studded with the other-worldly giant lobelia and groundsel plants. Spectacular scenery is the main attraction for hikers on this oft-neglected and relatively undemanding mountain, but there is also a variety of forest monkeys and small antelope, along with elephant and buffalo. A checklist topping 300 birds includes many species not recorded elsewhere in Uganda. Other attractions include ancient cave paintings close to the trailhead at Budadiri, and spectacular caves and hot springs within the crater.

Getting There
Mbale lies 3-4 hours from Kampala along a good tar road. The trailhead at Budadiri, 20km from Mbale, is accessible by public transport.

What to Do
Day walks from Budadiri or within the Mount Elgon Forest Exploration Centre; hikes of four days or longer traverse the peaks. Well worth visiting is the lovely Sipi Falls.

When to Visit
The lower slopes are fine throughout the year. The drier months (June to August, December to March) are best for hiking.

Where to Stay
Up-market lodge at Sipi Falls. Midrange hotels in Mbale. Budget lodging at Sipi Falls, Mbale and Budadiri. Within the park, camping only.