The Gorillas of Virunga

The diet of mountain gorillas largely consists of foliage. Over 50 different plants, whose leaves, shoots and stems are eaten, constitute gorilla food, Francis began. For shoots, the gorillas enjoy mainly the rainy season mountain bamboos, when green and still tender, eaten with trocatea plants. “Because the bamboo shoots are 84% water, the supplement of trocatea, young bamboo leaves, tsile’s leaves, stems, flowers and roots, celery’s stem without the tree bark, urela cameronesis’ leaves and stem bark, and dry season black berries grown on high altitude, provides a nutritious delicacy. Plus the bark of eucalyptus trees  are also eaten especially by Susa, the largest gorilla group, for medicinal purposes,” revealed Francis. The male gorilla or silverback is particularly skilled in his knowledge of herbal plants and it is known that when one of his group members becomes ill, the silverback will often lead the group to another sector of the park to find a particular herb and encourage the sick member of the group to eat it.

Eating also depends on the prevailing situation in a group and the weather. Normally gorillas have a three intervals of rest between each feeding, which amounts to 40% of their total time per day. However, if they have moved in an area that has plenty of food, they will feed and then rest for longer periods compared to times and movement into a sector of limited food availability. In addition, if it’s raining heavily they become dormant; active again when it stops.

Since we had opted to trek the Susa group, which was referred to as the furthest and most difficult to find, we felt the rain was doing us a favour by making them dormant. At least we will find them easily, we thought to ourselves.  We walked through the thick vegetation, which the rain made practically impassable. Several times the wet, slippery grass saw many of the trackers slipping and sliding, with some holding on to trees for support.  After persevering for 6 hours, climbing 3700metres, we were told by the rangers to sit only to find that we were completely surrounded by the group. The rangers made grunting noises to ensure the silverback that we were friendly and the silverbacks grunted in return.  In effect, the rangers were communicating with the gorillas.  With gorillas sitting all around and the babies swinging playfully in the low trees and one playful baby holding on to a tourist’s shoes, the one-hour view of the wider nasal cavity, broad chest, black shaggy hair with silverback males striking a contrast, we were amazed.  It was a truly exhilarating experience and something I will remember for the rest of my life.

Resting, as a major component of the gorillas’ social setting, involves playing - which varies with age groups. One activity, grooming, entails looking for and killing parasites from each others’ furry bodies. After a siesta, mating occurred between a silverback and a mature female and we were able to see the actual forming of nests in the evening, in an area identified by the dominant silverback.

Forming of nests is mainly the bending of soft trees, breaking mature bamboo sticks and other tree species that have broad leaves to provide a blanket and shield against the cold. Mothers find a comfortable spot where their backs will be supported as they breastfeed and cuddle their babies for the night. “A mother gorilla will breastfeed her baby for three and half years and will have a maximum of six babies with a spacing of four years,” Francis commented as he further added that seeing nests is one of the indicators that guides use to tell how far trackers will go before reaching the climax of the adventure.

Rwanda has eight groups of gorillas. Each group has a strict hierarchy based on age, indicated by how a young one will vacate an eating point, playing space or sleeping area in a particular area for the elder. Five groups are the ones typically seen during trekking. These are identified differently according to the numbers that constitute a group. Sabinyo group has 11, Susa has 39 after the death of a baby gorilla on January 12th, Amahoro has 14, Umubano has 8 and group number 13 includes 17gorillas. Though most times tourists desire to track Susa because of its large gorilla composition, Francis says numbers do not mean a thing. Each group has something unique that makes it stand apart.  For instance, one group may have the biggest silverback, another the most playful children or an easy to interact with silverback, among other traits, that make tracking each group a unique experience.  Nevertheless, seeing a particular group very much depends on where it is that day as gorillas are always on the move in search of food and safety.

By virtue of their habitat, Francis added, gorillas do not have many predators. Apart from the buffaloes, golden monkeys and elephants that share and live in harmony with the gorillas in lower altitudes, gorillas live in cold conditions which other animals cannot stand, giving them a monopoly of the mountain areas. Francis explained that they are able to live in such cold conditions because of their black colour pigment. “The black colour helps to attract and trap heat in the high altitudes of the mountains and at the same time makes gorillas less susceptible to heat stroke as they love sun bathing. Gorillas in this region can live up to 45 years with the silverbacks weighing about 200kg and females between 80 to 120kg.”

After enjoying the antics of the young gorillas and the sheer size of the male, with the one hour view seeming like only 15 minutes, we headed back down the mountain to a hot coffee and a well-earned rest.