Mountain Gorillas Safaris in Africa: Go Gorilla Trekking Rwanda, Uganda & DR congo
The mountain gorilla (Gorilla beringei beringei) is one of the two subspecies of the eastern gorilla as it listed as endangered by the IUCN as of 2018.
The two populations are Virunga volcanic mountains of centarl africa for the three national parks which are Mgahinga in siuth west, volcanoes in north west rwanda and virunga in the , eastern (DRC).
The other population is found in Uganda in bwindi impentetrable national park. Some primatologists speculate the Bwindi population is a separate subspecies and it’s description has not been finalized. But in june 2018 more than 1000 indivudials were there ..
Evolution, taxonomy and classification
Gorilla taxonomy
Mountain gorillas are found in Africa and Arabia in the start of the Oligoceneepoch(34-24million years ago) and are descendants of ancestral monkeys and apes .The evidence of the hominoid primastes (apes)found in the east Africa about 22-32 million years ago is got from the fossil record. And however poor the fossil record of the area the mountain gorillas lie there and so its evolutionary history is also not clear … about 9 milions years ago the group of primates that were to form into gorillas split from their common ancestors with the humans and chimps and it is when the genus gorilla emerged though not clear what the early relative of the gorilla was and is traced back to the early ape proconsul africanus. Mountain gorillas have been isolated from eastern lowland gorillas for about 400,000 years and these two taxa separated from their western counterparts approximately 2 million years ago.there has been a continuous and unfinished debate over the classification of the mountain gorillas.. In 1847, genus was reffered to as troglodytes and 1852 it was now renamed gorill. And in 1967 it was proposed that all gorillas be known as one species with three sub-species Gorilla gorilla gorilla (western lowland gorilla), Gorilla gorilla graueri (lowland gorillas found west of the Virungas) and Gorilla gorilla beringei (mountain gorillas, including Gorilla beringei, found in the Virungas and Bwindi). In 2003, after a review, they were divided into two species (Gorilla gorilla and Gorilla beringei) by The World Conservation Union (IUCN)
Habitat and ecology
The mountain gorilla inhabits the Albertine Rift montane cloud forests and theVirungaVolcanoes ranging in altitude from 2,200–4,300 metres (7,200–14,100 ft).Karisimbi , mikeno and viseko are the three domant slopes were the mountain gorillas are found .The vegetation is very dense at the bottom of the mountains, becoming more sparse at higher elevations, and the forests where the mountain gorilla lives are often cloudy, misty, and cold
The mountain gorilla is primarily a herbivore; the majority of its diet is composed of the leaves, shoots, and stems (85.8%) of 142 plant species. It also feeds on bark (6.9%), roots (3.3%), flowers (2.3%), and fruit (1.7%), as well as small invertebrates. (0.1%).Adult males can eat up to 34 kilograms (75 lb) of vegetation a day, while a female can eat as much as 18 kilograms (40 lb
The home range size (the area used by one group of gorillas during one year) is influenced by availability of food sources and usually includes several vegetation zones. George Schaller identified ten distinct zones, including: the bamboo forests at 2,200–2,800 metres (7,200–9,200 ft); the Hagenia forests at 2,800–3,400 metres (9,200–11,200 ft); and the giant senecio zone at 3,400–4,300 metres (11,200–14,100 ft). The mountain gorilla spends most of its time in the Hagenia forests, where gallium vines are found year-round. All parts of this vine are consumed: leaves, stems, flowers, and berries. It travels to the bamboo forests during the few months of the year when fresh shoots are available, and it climbs into subalpine regions to eat the soft centers of giant senecio trees..
Behaviour
Social structure
The mountain gorilla is very social, and it lives in relatively stable, cohesive groups held together by long term bonds between adult males and females. Relationships among females are relatively weak. These groups are nonterritorial; the silverback generally defends his group rather than his territory. In the Virunga mountain gorillas, 4.7 years is the average length tenure for a dominat silver back .One adult male is composed of 61% and anumber of females and 36% contain more than one adult male .the other mountain gorillas are either lonely males or only male group and made up of one mature male and not very many younger males.
Each group size varies from five to thirty and it has about ten inviduals Group sizes vary from five to thirty ,the composition of a typical group include: one dominant silverback, who is the group’s undisputed leader; another subordinate silverback that is an adult son of dominant silverback, ayounger brother .one or two blackbacks and they behave as sentries; three to four sexually mature females, who are ordinarily join to the dominant silverback for life; and from three to six juveniles and infants.
60% of the females and almost all the male mountain gorillas leave their place or time of birth. When the males make 11 years old they leave and the separation process is often very slow, they spend more and more time on the edge of the group until they leave altogether.while travelling they might be alone or with a male group for 2–5 years before attracting females to join them and form a new group. And the females leave when they are about 8 years to either begin a new group with a lone male or transfer directly to an established group. Females often transfer The mountain gorilla females move to a new group many times before settling down with a certain silverback male
The dominant silverback always determines the movements of the group, taking it to better feeding sites throughout the year. The dominant silverback brings about peace incase of conflicts within the group and protects it from external threats.incase of any attack by the humans, leopards or any harmful creature, the silverback can even give in his own life to protect the group .Him being the center of attention during rest sessions, the young gorillas always stay next to him and consider him being in their games. .Incase of any deaths or mother leaving the group the silverback is the who takes care of the abandoned offspring, and gives them space in his nest to sleep Experienced silverbacks are capable of removing poachers’ snares from the hands or feet of their group members
Ending the life of the silverback, the group may be disrupted. Unless there is an accepted male descendant capable of taking over his position, the group will either split up or adopt an unrelated male. And when a new silverback joins the family he may kill all the infant of the old(dead) silverback. Intentional killing of infants has not been observed in stable groups.
Analysis of mountain gorilla genomes by whole genome sequencing indicates that a recent decline in their population size has led to extensive inbreeding. As an apparent result, individuals are typically homozygous for 34% of their genome sequence. Furthermore, homozygosity and the expression of deleterious recessive mutations as consequences of inbreeding have likely resulted in the purging of severely deleterious mutations from the population.
Aggression
However much strong and powerful the mountain gorillas are very shy and gentle .in stable groups of the mountain gorillas severe aggression is rare, but when two mountain gorilla groups meet, the two silverbacks can sometimes engage in a fight to the death, using their canines to cause deep, gaping injuries. And in so doing the conflicts are most often resolved by displays and other threat behaviors that are intended to intimidate without becoming physical. The ritualized charge display is unique to gorillas. And these are the nine steps of the whole order :-1.progressively quickening hooting. 2. symbolic feeding. 3. rising bipedally. 4. throwing vegetation . 5. chest-beating with cupped hands. 6. one leg kick . 7. sideways running four-legged. 8. slapping and tearing vegetation . 9. thumping the ground with palms .
Affiliation; the state of being closely associated
Mutual grooming reinforces social bonds, and helps keep hair free from dirt and parasites. It is not as common among gorillas as in other primates, females groom their offspring regularly. Young gorillas play often and are more and live a lot in the tress than the large adults. Playing also contributes to the way they communicate and behave within the group. Activities include wrestling, chasing, and somersaults. If encouraged , the silverback and his females can even participate in the games
Vocalization
Twenty-five distinct vocalizations are recognized, within the dense vegetation many are used primarily for group communication. While travelling, sounds classified as grunts and barks are heard and the whereabouts of individual group members is indicated . ] They may also be used during social interactions when discipline is required. Silverbacks most often produce the screams and roars signal alarm or warning. During feeding and resting period the rumbling belches suggest contentment and are heard frequently .They are the most common form of intragroup communication.
Fears
The mountain gorillas appear to be naturally afraid of certain reptiles and insects for unknown reasons. The infants, have a natural behavior that is to chase anything that moves, they will go out of their way to avoid chameleons and caterpillars. They are also afraid of water and will cross streams only if they can do so without getting wet, such as by crossing over fallen logs, and dislike rain.
Conservation
Population size and growth rates
The increase in overall population of the mountain gorillas has been brought about by the Conservation efforts (Gorilla beringei beringei) in the Virungas and Bwindi. The overall population is now believed to be at over 1,000 individuals. The increase of the number of mountain gorillas living in the tri national forested was announced by the official website of Virunga National Park in December 2010, an average growth rate of 3.7% per year. During the 2010 census , it was estimated that 480 mountain gorillas inhabited the region as the 2003 census estimated that the Virunga gorilla population had 380 individuals, and it represented a 17% increase in the total population since 1989, where we had 320 individuals. Since then the population has doubled its lowest point in 1981, when a census estimated that only 254 gorillas remained.
In 2006 , the census at Bwindi showed a population of 340 gorillas, and it happened so to represent a 6% increase in total population size since 2002 and a 12% increase from 320 individuals in 1997.And all the estimates were a means of the traditional census methods were dung samples were used and collected at night nests. The genetic analyses of the entire population during the 2006 census indicated there were only approximately 300 individuals in Bwindi..
The groups of gorillas that were habituated (habitution means that through repeated, neutral contct with humans) for research and ecotourism have higher growth rates than unhabituated gorillas in both bwindi and virungas and this was according to computer modeling of their population dynamics, the normal behavior of the gorilla is got when people are in proximity. On seeing the goriilas that are more closely guarded by field staff one should tell that they are habituated and they are given veterinary treatment for snares, respiratory disease, and other life-threatening conditions. Researchers recommend that some gorillas remain unhabituated as a bet-hedging strategy against the risk of human pathogens being transmitted throughout the population.
Despite the population growth, the mountain gorillas remain threatened.
Poaching:
Mountain gorillas are not usually a taste for bush meat, but they are mostly killed by traps and snares intended for other animals. They have been killed for their heads, hands, and feet, which are sold to collectors. Their infants are sold to zoos, researchers who want them, and pet lovers. The illegal removal of the infants from their parents generally involves the loss of at least one adult, as members of a group will fight to the death to protect their young. The Virunga gorillas are particularly susceptible to animal trafficking for the illegal pet trade. With young gorillas worth from $1,000 to $5,000 on the black market, poachers seeking infant and juvenile specimens will kill and wound other members of the group in the process. The group that survives often disband. Taping 4 in well known as the one documented case . And in the same situation, a Malaysian Zoo received four wild-born infant gorillas from Nigeria at a cost of US$1.6 million using falsified export documents. Poaching for meat is also particularly threatening in some regions. Most of the African great apes survive in areas of chronic insecurity, where there is a breakdown of law and order. In January 2007 there was a killing of mountain gorillas at Bikenge in Virungas national park and it was a well-documented case. During the 1994 Rwanda genocide some poaching activites were also linked to the genral break down of law and order..
Habitat loss:
It has been the most severe threat to the gorillas. The forests where mountain gorillas live are surrounded by rapidly increasing human settlement.And the main cause of fragmentation and degradation is through shifting agriculture known as slash-and-burn, pastoral expansion, and logging, villages in forest zones. Virunga Conservation Area of Rwanda’s national park reduced by more than half of its original size to support the cultivation of Pyrethrum. And the mountain gorilla population reduced in numbers by the mid of the 1970s. The resulting deforestation confines the gorillas to isolated deserts. The impact of habitat loss extends beyond the reduction of suitable living space for gorillas. Human settlement has lead to gorilla groups increasinging geographically and isolated from one another and the genetic reeduction of each group. Inbreeding is one of the signs appearing in younger gorillas and also webbed hands and feet.
Disease: Although the mountain gorillas are proctected, there is also a risk from people of a more well-meaning nature. Groups subjected to regular visits from tourists and locals are at a continued risk of disease cross-transmission and there is a rule that humans and gorillas be separated by a distance of 7 metres at all times to prevent the uncessary diseases. And, by some researchers, infectious diseases have 20% of sudden deaths in mountain gorilla populations. With the implementation of a successful ecotourism program in which human-gorilla interaction was reduced during the period of 1989–2000 four sub-populations in Rwanda experienced an increase of 76%. By contrast, seven of the commonly visited sub-populations in the Democratic Republic of Congo (DRC) saw a reduction of almost 20% over only four years (1996–2000). The negative impacts of ecotourism on gorilla health can be reduced only if proper management is undertaken.
The human origin also is at risk of disease transmission; pathogens from domestic animals and livestock through contaminated water ..Studies have found that waterborne, gastrointestinal parasites such as Cryptosporidium sp.,Microsporidia sp.,and Giardia sp. are genetically identical when found in livestock, humans, and gorillas, only along the border of the Bwindi Impenetrable Forest. Tuberculosis is another disease that can attack the humans. 11% of cattle in Rwanda suffered from this affliction.
War and civil unrest:
These three countries rwanda, Uganda, and the Democratic Republic of Congo have been surrounded by military forces by war and civil unrest and their unstability politically over the last years. Using simulation modeling, Byers set al. (2003) have suggested that times of war and unrest have negative impacts on the habitat and populations of mountain gorillas. And examples include the 1994 Rwanda genocide that has taken place approximately every 30 years, with each event lasting for approximately 10 years. When human encounters increase both aggressive and passive result in a rise in mortality rates and a decrease in reproductive success. More direct impacts from conflict are also seen. According to Kanyamibwa the mines were placed along trails in the volcanoes national park and as a result many gorillas were killed . The habitants were destructed as refugees fled the cities and cut down trees for wood leaving the gorillas homeless.
Conservation efforts
The International gorilla Conservation Programmeis a non-governmental organization best known in conservation of mountain gorillas and it was established in 1991 as a joint effort of the African Wildlife Foundation, fauna and flora International together with the World Wide fund for nature. Conservation needs work at many levels, from local to international, protection and law enforcement as well as research and education is also involved. The break down conservation efforts were by the Dian Fossey and were done in the following categories .. and these categories are three in number ;
Active during conservation frequent patrols in wildlife areas are used to destroy poacher equipment and weapons, firm and prompt law enforcement, census counts in regions of breeding and ranging concentration, and strong safeguards for the limited habitat the animals occupy.
Theoretical on improving existing roads that circle the mountains, conservation encourages growth in tourism and also by renovating the park headquarters and tourist lodging, and by the habituation of gorillas near the park boundaries for tourists to visit and take photos
Community-based biodiversity protection is encouraged bny the conservation management by and with the local community; and it is applied in varying degrees. The process seeks equity between meeting the needs of the local population and preserving the protected areas, and local people are there to make decision.
Bwindi Impenetrable National Park has a successful collaborative management process. In 191 the forest was designated a national park it happened with little community consultation and the new status left the local people out from accessing resources within the park as well as reducing economic opportunities. Number of forest fires were lit and threats were made to the gorillas.. Surveys of community attitudes conducted by CARE show a steadily increasing proportion of people in favoring the park. Surprisingly, the cases of deliberate burning has not been mentioned any where and the problem of snares in these areas has been reduced. Kwita Izina (in 2005) was a ceremony introduced but has also had some impact in getting the gorillas s attention about preservation and its importance to local communities.
While community-based conservation bears out individual analysis, There are significant overlaps between active and theoretical conservation while community based conservation bears out individual analysis and a discussion of the two as halves of a whole seems more constructive. For example, Rwanda’s national parks went through a restructuring process were Eugene Rutagarama stated that “They got more rangers on better salaries, more radios, more patrol cars and better training in wildlife conservation. They also built more shelters in the park, from which rangers could protect the gorillas. Tourism funds most of the improvements . Around 20,000 tourists visited gorilla populations in Rwanda, getting around $8 million in revenue for the parks.
Tourism is seen as a “high value activity that gets enough revenue to cover park management costs and contribute to the national budget of the Uganda Wildlife Authority that is for the country Uganda.
Mountain gorillas (eastern gorillas) are found in two isolated groups. One group is the Virunga region which is mark a border of three countries of Uganda, Rwanda and Democratic Republic of Congo. The second group is found in Bwindi Impenetrable National Park which is located in the south western part of Uganda.
The world population of mountain gorillas has increased to 880 individuals according to the census data released by the Uganda wildlife authority in 2010. A mountain gorilla has thick and longer fur and shorter arms than other gorilla species which enables them to live in high altitude areas. Mountain gorillas have long silky black coats with hairless face, palms, soles and chest.
They are remarkably strong with a broad chest and shoulders. They are also bigger than other species. Males weigh around 195kg and females weigh around 100kg. Females have a gestation period of 8.5months. They live in highland tropical forests of Africa and stay in altitudes ranging between 8000 and 1000 feet. Mountain gorillas live in groups of up to 30 individuals.
The group, or troop, is led by a single alpha male, an older silverback. These males are called silverbacks because of the silver stripe they develop on their backs when they mature. The oldest males of the group are at least 12 years old.
These troops also include several younger males, adult and juvenile females, and infants. In addition to providing protection to group members, silverbacks maintain order and decide all activities within their troop. They schedule feeding trips, resting time, and travel.
They also father the majority of the young in the group. Threats The biggest threats to these great apes come from deforestation and the growing human population around the area, diseases, and wars and civil unrest. Gorillas are not commonly poached but they always fall in traps meant for other animals.