Gorilla

TAXONOMY

Suborder: Haplorrhini Infraorder: Simiiformes Superfamily: Hominoidea Family: Hominidae Genus: Gorilla Species: G. beringei, G. gorilla Subspecies: G. b. beringei, G. b. graueri, G. g. diehli, G. g. gorilla Other names: gorilla (Finnish); gorille (French); gorilla (German); gorila (Spanish); bergsgorilla, gorilla, or låglandsgorilla (Swedish); G. gorilla: western gorilla; G.g. diehli: Cross River gorilla; G.g. gorilla: western lowland gorilla; G. beringei: eastern gorilla; G.b. beringei: Bwindi, mountain, or Virunga; G.b. graueri: eastern lowland gorilla or Grauer’s gorilla

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SOCIAL ORGANIZATION AND BEHAVIOR

Current knowledge on the social organization and behavior of gorillas is dominated by results from research on mountain gorillas though there are some data for eastern and western lowland gorillas. The minimum group size for all subspecies is two individuals (usually a silverback and a female), except for males ranging alone, while maximum group size varies slightly for each subspecies (Yamagiwa et al. 2003). The maximum group size for mountain gorillas can exceed 20 individuals, while eastern and western lowland gorillas generally are not found in groups larger than 17 to 20 individuals and western lowland gorilla groups are always observed in groups smaller than 20 individuals (Yamagiwa et al. 2003). Mountain gorillas live in age-graded groups of, on average, 9.2 individuals, with one adult male (though there may be more than one), multiple adult females, and their offspring (Watts 1996; Doran & McNeilage 1997; Robbins 2001). Natal dispersal is much more common for females than for males in mountain gorillas (Watts 1996). In general, females emigrate from their natal groups to avoid inbreeding. They do not always stay in their new groups throughout their lives and secondary transfer is common (Watts 1996; Robbins 2001). Males either remain in their natal groups or disperse. If young males remain in their natal groups, they will be subordinates to the silverback, but may have the opportunity to mate with new females or become dominant if the silverback dies. The other strategy for mountain gorilla males is to leave their natal groups and become solitary, attracting emigrating females and starting new social groups. In groups containing only one silverback male, females disperse and find new social groups upon the death of the silverback (Yamagiwa & Kahekwa 2001). This may be related to high rates of infanticide documented among mountain gorillas at Karisoke. Infants deprived of protection by an adult male are almost certain to be killed and as a tactic to protect against this, females join new groups in the absence of a silverback (Watts 1989). Until recently, infanticide had only been recorded among mountain gorillas; direct evidence now exists for eastern lowland gorillas and indirect evidence has been recorded among western lowland gorillas (Stokes et al. 2003; Stoinski pers. comm.). Finally, males can live in all-male groups, although this seems to be a strategy generally employed by young males when their group disintegrates before they reach adulthood (Stoinski pers. comm.). Eastern lowland gorillas generally live in groups of one male, multiple females, and their offspring, though these can shift to multi-male groups for brief periods (Yamagiwa et al. 2003). The average group size is 9.8 individuals (Yamagiwa & Kahekwa 2001). Males spend a few months to a few years alone after emigrating from their natal groups at or before the age of 15, eventually attracting dispersing females and creating a new social group (Yamagiwa et al. 2003). Average age of transfer for female eastern lowland gorillas is nine (Yamagiwa & Kahekwa 2001; Yamagiwa et al. 2003). Female gorillas do not always emigrate independently; sometimes they transfer with another female to join a solitary male. Group succession, as seen in male mountain gorillas that remain in their natal groups, has not been observed in eastern lowland gorillas. If the silverback dies, the multi-female group and their offspring may continue to associate, rather than disperse, until a maturing silverback transfers into the group (Yamagiwa & Kahekwa 2001). One possible explanation for this behavior is protection against predators. Rather than roaming with just their offspring, females remain in groups of unrelated individuals to decrease chance of being attacked by leopards (Yamagiwa & Kahekwa 2001). Difficulties with habituation and ecological constraints on observation have limited the research on social behavior of western lowland gorillas (Magliocca et al. 1999; Parnell 2002; Stokes et al. 2003). Group composition in western lowland gorillas is generally one silverback, multiple females, and their offspring with groups averaging 8.4 individuals (Parnell 2002). Groups with two silverbacks have been observed at several sites (Stoinski pers. comm.). Males generally emigrate from their natal groups and are solitary, as is seen in eastern lowland gorillas. Western lowland gorillas were not thought to live in bachelor groups btu there is now evidence from several sites that males will coexist without breeding females; group composition generally consists of a single adult male plus several younger males and nonreproductive females (Stoinski pers. comm.). Both natal and secondary transfers are observed in female western lowland gorillas and, as is seen in mountain gorillas, when the silverback dies, groups disband and females immigrate into new groups (Stokes et al. 2003). Though it has never been directly observed among western lowland gorillas, infanticide is the probable cause of this behavior. Females protect against infanticide when their resident silverbacks die by seeking the protection of other adult males in new groups (Stokes et al. 2003). Knowledge about social relationships is most extensive for mountain gorillas. The core of social groups is the male-female bond, which is reinforced by grooming and close proximity (Watts 2003). It is important for female mountain gorillas to develop strong relationships with males because males offer such services as protection against predators, protection against infanticide by other males, and mating opportunities (Watts 2001). It is common to see aggressive behavior between males and females, though rarely is it intense or does it lead to serious injury (Watts 1996). Female-female relationships vary, but generally differentiate along lines of relatedness; maternal relatives associate closely and often affably interact. Generally, though, female gorillas have limited friendly relationships and multiple aggressive encounters (Watts 1996). These aggressive encounters often revolve around social access to males, and males intervene in contests between females (Watts 2003). Relationships between male gorillas are generally weak, especially in heterosexual groups where the dominance hierarchy is quite apparent and there is strong competition for mates. Relationships between members of all-male groups, in those subspecies where they occur, are slightly more affiliative, and they socialize through play, grooming, and close proximity (Robbins 2001).

REPRODUCTION

Data from wild mountain gorillas and captive western lowland gorillas provide the majority of information about reproductive parameters of gorillas and the differences between the subspecies are few. Menarche occurs in female gorillas around age six and is followed by a period of adolescent infertility that usually lasts two years (Czekala & Robbins 2001). The estrus cycle lasts between 30 and 33 days and there are very subtle outward signs of ovulation, unlike the very obvious sexual swellings seen in chimpanzees (Pan troglodytes) and bonobos (P. paniscus). Gestation lasts 8.5 months. For wild mountain gorillas, the average age at first parturition is 10 years and the interbirth interval is four years (Czekala & Robbins 2001). It is more difficult to assess male reproductive maturity because they can be fertile before exhibiting secondary sexual characteristics (the silver saddle that characterizes adult males). Males between eight and 12 years are called blackbacks (Robbins 2001). In captivity, though, males can sire offspring by the age of six (Stoinski pers. comm.). Usually by age 12 or 13, males can be considered silverbacks, but most will not reach their full adult size until the age of 15 (Czekala & Robbins 2001). There is no evidence of birth seasonality and mating occurs year-round (Watts 1991; 1998). A female will initiate copulation by pursing their lips and slowly approaching a male, establishing prolonged eye contact. If he does not respond she may reach towards him, touch him, or slap the ground in front of her to attract his attention (Sicotte 2001). In groups with multiple males, solicitation is taken as indication of female preference, though females may be coerced to mate with multiple males during the estrus period (Sicotte 2001). A male initiates copulations by approaching the female and displaying at her or touching her and giving a “train grunt” vocalization (Watts 1991).

PARENTAL CARE

Since mortality is as high as 38% in mountain gorillas during the infancy period (from birth to three years), caregivers, primarily females, are acutely important in the survival of their infants (Watts 1989). Because of their long period of development and dependence, gorilla mothers can expect to invest years caring for their vulnerable offspring. Although male gorillas do not take an active role in caring for infants, they play an important role in their socialization, often associating with older infants and juveniles (Stewart 2001). The relationship that develops between the silverback and infants in his group is usually supportive; he serves as an attachment figure during the difficult time of weaning and he shields young gorillas from intragroup aggression by intervening in disputes involving older, more dominant individuals (Stewart 2001). For the first five months of life, infant mountain gorillas remain in constant contact with their mothers and females seek close proximity to their resident silverback for protection (Stewart 2001). During this period, infants are dependent on their mothers for food, suckling at least once per hour, and sleep at night in their mothers’ nests (Stewart 1988). After five months, mother-infant pairs break body contact, but only for a few seconds and by 12 months, infants venture up to, but never more than, five meters (16.4 ft) away from their mothers. By 18 to 21 months, this distance between the pair is regular and increases (Fletcher 2001). Concurrent with this decrease in proximity is a decrease in nursing frequency, with infants only nursing once every two hours (Stewart 1988). By the age of 30 months, infants spend only half of their time with their mothers. The juvenile period is from three to six years and is characterized by a decrease in maternal grooming, no longer sharing a sleeping nest with the mother, and weaning (Stewart 2001). Because of the enormity of the task of rearing infants and the stress of lactation on the mother’s body, female gorillas experience lactational amenorrhea until the infant is weaned at three or four years. After the infant is weaned, the mother begins to ovulate and shortly thereafter becomes pregnant (Stewart 1988; 2001). Weaning conflict is minimized in gorillas, compared to other great apes, because of the cohesive nature of gorilla groups. The constant availability of play partners (including the silverback) may contribute to less intense conflict between mother and infant during this period (Fletcher 2001).

COMMUNICATION

Vocal communication among gorillas is important in within-group interactions as well as extra-group interactions. Within-group calls, include “copulatory grunts” and “whimpers” during copulation, “whines” and “whimpers” by infants, “play chuckles” during play, “intense” and “mild cough grunts” during mild threat displays, and “close” calls that include both “syllabled” and “non-syllabled” calls such as “train-grunts” and “dog whines” (Fossey 1972; Harcourt et al. 1993). “Close” calls are commonly given within the group in situations of either potential separation or potential conflict. Extra-group calls serve to alert group members of potential predation and include “barks” or are given as long-distance threat displays upon detection of another group and include the “hoot series,” which may be accompanied by chest beating (Fossey 1972; Harcourt et al. 1993). Most calling occurs within-groups during feeding times, though gorillas also call during rest periods as well (Harcourt et al. 1993).

LISTEN TO VOCALIZATIONS

• Gorilla gorilla beringei: Belch  (African Primates at Home/Indiana University)
• Gorilla gorilla beringei: Chest-beat  (African Primates at Home/Indiana University)
• Gorilla gorilla beringei: Grunts, chestbeating  (Wild Sanctuary)

The communicative abilities of gorillas have also been studied in captivity, and one gorilla in particular, has been the focus of studies trying to understand language acquisition in humans. For over 30 years Francine Patterson has worked with Koko, a western lowland gorilla, teaching her American Sign Language and English. Today Koko can use over 500 signs and understand spoken English, though the physiological differences between apes and humans make it impossible for her to speak (Patterson & Gordon 2001).

Content last modified: October 4, 2005

Written by Kristina Cawthon Lang. Reviewed by Tara Stoinski.

Cite this page as: Cawthon Lang KA. 2005 October 4. Primate Factsheets: Gorilla (Gorilla) Behavior . <http://pin.primate.wisc.edu/factsheets/entry/gorilla/behav>. Accessed 2020 July 22.

  See also the Gorilla Gazette, a newsletter about gorilla care and conservation created by gorilla keepers at the Columbus Zoo and published from 1987-2013.

INTERNATIONAL STATUS

For individual primate species conservation status, please search the IUCN Red List. Also search the current scientific literature for primate conservation status (overall as well as for individual species), and visit CITES (Convention on International Trade in Endangered Species of Wild Fauna and Flora).

Conservation information last updated in 2005 follows, for comparison: Gorilla All gorillas face a very high risk of extinction in the wild in the near future if current threats do not subside. Hunting, forest clearance for agriculture and timber, and disease are the main threats to gorilla survival and these problems continue to increase in intensity and extent. Gorillas, like many African primates, are also subject to human warfare in parts of their range.

CONSERVATION THREATS & POTENTIAL SOLUTIONS

Threat: Human Induced Habitat Loss and Degradation

Habitat loss and modification due to human activity is a primary threat to gorilla survival. Agriculture, logging, fuelwood and forest product collection, and grazing domestic animals all degrade gorilla habitat and are problems that only increase as the human population in Africa grows (Plumptre et al. 2003). Only about 20% of gorillas live inside protected areas where, in theory, they are safe from habitat modification by encroaching humans. The remaining 80% are severely threatened by human induced habitat modification (Harcourt 2003). Mountain gorillas, while numbering only a few hundred, live in well-protected national parks known as the Virunga Conservation Area comprised of Parc National des Virunga, Parc National des Volcans, and Mgahinga Gorilla National Park (Steklis & Gerald-Steklis 2001). Habitat destruction has subsided in this area in recent years (Tutin & Vedder 2001; Plumptre et al. 2003). The growing human population on all sides of the mountain gorillas’ habitat allows for little buffer between the apes, and human activities like cattle grazing and collection of forest products have been problematic in the past and may become so in the future if political instability results in another civil war (Oates 1995; Steklis & Gerald-Steklis 2001). Eastern lowland gorillas living in war-torn DRC are losing habitat faster than any other gorilla population (Plumptre et al. 2003). Logging, agriculture, and livestock grazing are all important economic activities for humans that lead to habitat modification in the eastern lowland gorilla’s range. Lowland populations are being forced into higher altitudes where steep slopes are not conducive to farming or ranching, isolating the population even further (Ilambu 2001). Following wars in 1996 and 1998-99, a huge influx of refugees from Rwanda compounded the problem as more pressure was put on the forest for fuelwood and food collection. The potential far-reaching effects of this sudden increase in human population will not be known for some time (Ilambu 2001; Tutin & Vedder 2001). Mining prospects in DRC are also having devastating effects on the habitat and gorilla population (Stoinski pers. comm.). Ecotourism can be a positive, revenue-earning undertaking for some communities, but when poorly managed can have negative impact on the animals or ecosystems it has been implemented to save. In the case of eastern lowland gorillas, ecotourism has had a negative impact on the gorillas and their habitat. Implemented as a source of revenue for local communities, the large groups of frequent visitors severely impacted high-altitude vegetation and were disturbing to the gorillas (Tutin & Vedder 2001). The majority of western gorillas live outside protected areas and are therefore most at threat from human induced habitat modification. Fortunately, though, where gorillas exist in the remote forests of the Congo Basin, they are not subject to human disturbance. Interestingly, though, gorillas can coexist with logging because they tend to favor the areas of secondary vegetation that grow after an area has been clear cut (White & Tutin 2001; Plumptre et al. 2003). Unfortunately, with logging comes habit fragmentation by logging roads and easy access by hunters. Forest products are in increasing demand in some parts of their range where human populations are high and continuing to grow, including Nigeria (Cross River gorilla), southern Congo, and parts of Equatorial Guinea (Tutin & Vedder 2001).

Potential Solutions

Great strides have been made in reversing the population decline of mountain gorillas. With the support of notable gorilla researcher Dian Fossey, the Mountain Gorilla Project was launched in Rwanda in 1979 and included multiple approaches to conservation including education, ecotourism, and patrols to keep people and cattle out of the protected habitat (Steklis & Gerald-Steklis 2001; Tutin & Vedder 2001). While the Mountain Gorilla Project became the International Gorilla Conservation Program and continues its work today, many other organizations have been involved in similar programs aimed at educating local people, mountain gorialls have become a source of regional and national pride in Rwanda (Tutin & Vedder 2001). More security is needed surrounding the Kahuzi-Biega National Park, where eastern lowland gorillas are studied (Tutin & Vedder 2001). Though ecotourism was successful at this site at one time, poor management led to the disturbance of the gorilla population and the destruction of habitat. Because the interest still exists and it is quite a lucrative undertaking, well-managed ecotourism operations focusing on small groups of visitors at infrequent intervals may revive the local economy of this area of DRC. Unfortunately, political instability in the region may prevent this option currently, and some effort should be made to secure the region from encroachment of human populations that extract forest resources, by using guards and continued presence of researchers. Columbotantalite (also called Coltan) reserves scattered throughout DRC have also drawn thousands of people into gorilla habitat, affecting the gorilla populations. An ore used to make semiconductors for electronics, including cell phones and computers, in the late 1990s coltan was sold for US$80 per kilogram and was an attractive prospect for people who made less than US$30 per month (Plumptre et al. 2003). Unfortunately, huge reserves of this ore are found in Kahuzi-Biega National Park and thousands of settlers in mining camps severely affected the local population of eastern lowland gorillas. Western lowland gorillas that occupy swamp habitats that are unsuitable for commercial logging and are difficult to access by local people trying to extract forest products during the rainy season should be the focus of conservation activities. These areas have high population densities of gorillas and should be protected from future human incursion (Tutin & Vedder 2001). Though it is a difficult task to convince people to protect a population that is not currently severely at risk, it must be emphasized that these populations are healthy and will remain that way only if they are unharmed by habitat destruction in pristine forests (Tutin & Vedder 2001). Where western lowland gorillas are threatened by agriculture and selective logging (southern Republic of Congo and Equatorial Guinea), efforts should be made to establish protected areas in congruence with active field research sites. The major parks that have been established in western lowland gorilla range include Dzanga-Sangha National Park in CAR and Nouablale-Ndoki National Park in Congo (Tutin & Vedder 2001). Another key area that has not attained protected status is Lopé Faunal Reserve in Gabon where researchers have worked hard to habituate the gorillas.

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Threat: Invasive Alien Species

Gorillas are highly susceptible to human diseases, and where they are immunologically naïve, the influx of poachers, soldiers, local communities, and domestic animals facilitates the spread of pathogens in small communities (Mudakikwa et al. 2001; Plumptre et al. 2003). Gorillas in Republic of Congo and Gabon are currently threatened by an epidemic of Ebola hemorrhagic fever. Even in the most remote areas of their region, western gorilla populations have declined in congruence with human outbreaks of the disease and carcasses found have tested positive for Ebola (Walsh et al. 2003). Some other examples of zoonotic transfer include an epidemic of scabies, or sarcoptic mange, documented among a group of mountain gorillas in Bwindi Impenetrable National Park, the entire group was infected and it resulted in the death of an infant while respiratory illness claimed the lives of six mountain gorillas in the Virunga Volcanoes in 1988 (Wallis & Lee 1999). In the Virunga Conservation Area, emergency medicine and preventative health monitoring has been conducted by the Mountain Gorilla Veterinary Project since 1985 (Mudakikwa et al. 2001). The major groups that pose unique disease risk for mountain gorillas include local people, conservation personnel, and ecotourists (Mudakikwa et al. 2001). Though contact between gorillas and local people is limited to when they enter the park illegally or when gorillas leave the park boundaries and raid crops, this is significant enough to spread disease to the vulnerable gorillas including scabies, respiratory tract infections, intestinal parasites, skin disorders, and measles (Mudakikwa et al. 2001). Diseases are also transferred between park staff and tourists and gorillas as well, and while precautions are taken, this still poses a threat to the health of mountain gorillas.

Potential solutions

Educating local communities about zoonotic diseases may decrease disease transfer, and ideally, providing more widespread access to health care would also be useful. Where gorillas come in contact with researchers, park visitors, and staff, implementing even stronger protocol that includes face masks, gloves, required immunization, and further required distances from the animals may also decrease chances of disease transfer (Butynski 2001). Currently, field personnel working with the research populations of mountain gorillas take part in an employee health program designed to limit disease transfer to gorillas (Stoinski pers. comm.). In populations as small as the mountain and Cross River gorilla’s, it is imperative to minimize the possibility of infectious disease transfer as this could eliminate both populations entirely. Research on vectors of and vaccines for the Ebola virus are necessary to alleviate both human and ape suffering in regions where outbreaks occur (Walsh et al. 2003). Coupled with epidemiological research, law enforcement is necessary to prohibit contact between humans and apes, especially in targeted regions. This includes forecasting disease movement (among both humans and gorillas), anticipating where the next outbreak is likely to occur, and implementing strict policies and effective law enforcement measures to isolate potential outbreaks.

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Threat: Harvesting (hunting/gathering)

More threatening than habitat loss in some areas, hunting of gorillas for meat as well as capture of animals for collections are other hazards greatly affecting gorilla populations across Africa. Where human populations encroach on gorilla habitat and forest products such as fuelwood and timber are sought, poaching is generally also a problem, either for food or for sale (Plumptre et al. 2003). Mountain gorillas in the Virunga Conservation Area are heavily protected and although poaching had been reduced to zero), the past few years has seen a resurgence in poaching for infants for the pet trade (Stoinski pers. comm.). People living in the range of eastern lowland gorillas have traditionally had taboos against eating gorillas, though these customs are being quickly replaced. Civil war in DRC has led to mass hunger in the area as well and more often eastern lowland gorillas are being eaten for subsistence (Plumptre et al. 2003). Mining coltan in Kahuzi-Biega National Park has also led to drastic declines in gorilla populations, not simply because of habitat disturbance, but because of subsistence hunting by the thousands living in mining camps (Plumptre et al. 2003). Insecurity in the region prevents guards from stopping this influx of people and hunting will likely continue if the price of coltan increases in the future. Western gorillas that live in areas where logging activity is ever-increasing are also subject to hunting. Logging and the bushmeat market are inextricably linked and unfortunately, the social structure of western lowland gorillas makes them particularly susceptible to devastation by only a few hunters (Tutin & Vedder 2001). Entire groups of western lowland gorillas can be wiped out by a single or a few poachers. The silverback in a group will approach and display against any perceived threat, including poachers, and in doing so, he is an easy target and is quickly killed. Poachers will capture the infants for sale as pets, often killing the mother that is defending her infant (Tutin & Vedder 2001). Moreover, poachers are able to reach the dense, most remote areas of forests as logging companies establish roads and transportation from small towns and cities is available deep into the forests (Butynski 2001; Plumptre et al. 2003). Company employees living in small logging towns are able to afford meat, and it is often less expensive to purchase bushmeat than other sources of protein. Almost all facets of the bushmeat trade are controlled or facilitated by logging companies: they sell guns and ammunition, provide cable for snares, transport poachers into the forests on trucks, carry the meat out on trucks, employees purchase it in town, and boats and trucks transport the meat to larger markets in cities (Butynski 2001; Wilkie & Carpenter 2001).

Potential solutions

Economic value must be given to live gorillas if local communities are to stop pursuing them for meat. Alternately, world aid and development organizations must give fiscal incentives for gorilla-friendly development projects that include alternate protein sources. Education of local communities or stakeholders is also necessary if the bushmeat trade is to subside. Including stakeholders in research at field stations, guard duties, or education programs are all ways of providing economic opportunities and incentives for protecting gorillas as well as creating a bond between people and apes. Foreign logging companies must also be held accountable by the global community for their role in the bushmeat trade. Boycotts of tropical hardwoods in developed countries that purchase lumber from these companies or cancellation of logging concessions in countries where companies are actively involved in transporting bushmeat could help (Butynski 2001). Furthermore, gorilla-friendly certification programs by independent consultants could validate the practices of logging companies and provide an alternative to western consumers that are interested in tropical wood (Butynski 2001). In situ refuges and sanctuaries for orphan gorillas confiscated from markets play an important role in assisting law enforcement and as education centers for local people.

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Threat: Accidental Mortality

The bushmeat market targets more animals than primates, snares and traps are set for duikers, pigs, and rodents as well (Mudakikwa et al. 2001; Wilkie & Carpenter 2001). Unfortunately, snares are frequent causes of human-induced injuries to gorillas and can lead to loss of limbs or severely painful deaths if not treated (Mudakikwa et al. 2001). Gorillas that are caught in snares struggle to free themselves and are often cut on their limbs, hands, and feet; if these cuts become infected, without proper medical attention, the gorilla may likely die (Mudakikwa et al. 2001; Plumptre et al. 2003).

Potential solutions

Even with vigilant patrolling, snare removal is a constant challenge in areas where gorillas are sympatric with desirable animals (Hall et al. 1998; Plumptre et al. 2003). Mountain gorillas that encounter snares and are injured by them are treated by emergency medical staff of the Mountain Gorilla Veterinary Project. This process greatly decreases the chances of amputation and secondary bacterial infection. As the snare is removed, the wounds are cleaned and treated, and the injured animal is monitored to assess if follow up care is needed (Mudakikwa et al. 2003). Though there are great challenges and risks in undertaking this type of treatment for wild gorillas, it is a possibility for similarly habituated populations and has greatly reduced mortality caused by snare wounds among mountain gorillas. Snare patrols by researchers and field assistants coupled with intervention upon injury may decrease accidental mortality in gorillas.

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Threat: Persecution

Large and imposing, gorillas are often perceived as dangerous by most humans who share their range and their image is not helped when they periodically raid plantations in some areas (Hart & Hall 1996; Tutin & Vedder 2001). Furthermore, gorillas that attack and seriously injure farmers on land adjacent to parks are even more despised and targets for retaliation (Butynski 2001).

Potential solutions

Public education programs about gorillas may increase tolerance for them in local communities that come in contact with them on farms and plantations. Teaching members of the community about the uniqueness of gorillas and the ecosystem services they provide coupled with compensation for injuries or crops that are lost or damaged may improve gorilla-human relationships in some areas.

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Threat: Natural Disasters

Cross River gorillas live in a tiny fragment of forest in Nigeria and Cameroon where the dry season is long and the forest is susceptible to destructive fires. Fires started outside their range by local farmers, hunters, and pastoralists can get out of control and sweep through the dry forest, causing significant damage (Oates et al. 2003).

Potential solutions

Discouraging fire as a tool to clear land during this season is one approach to decrease the chance of forest fires. Limiting burning to certain times of year when the forest is not as vulnerable is another option to avoid devastating fires.

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Threat: Changes in Native Species Dynamics

Though gorillas and chimpanzees have overlapping ranges at multiple sites throughout Africa, the two apes do not compete for access to resources, in fact, they actively avoid competition by exploiting different niches during different times of year (Kuroda et al. 1996; Yamagiwa et al. 1996). The effect of leopard predation on gorilla populations is negligible (Fay et al. 1995).

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Threat: Intrinsic Factors

Long interbirth intervals and high infant mortality make reproduction a slow process for all subspecies of gorillas. While these intrinsic factors do not limit population growth by themselves, when disrupted by disease, abnormally high infant mortality, stress from disturbance, and other environmental hazards, recruitment may dwindle (Butynski 2001; Tutin & Vedder 2001). Higher mortality during the rainy season has been documented among mountain gorillas. Low temperatures coupled with heavy rainfall lead to conductive heat loss and respiratory infections (Watts 1998). Severely isolated populations of gorillas are threatened by the effects of limited gene flow, restricted range, and low densities. Small populations are at risk of inbreeding depression, are vulnerable to stochastic events, and genetic fixation of deleterious alleles is possible (Oates et al. 2003).

Potential solutions

The establishment of well-funded, well-run national parks is essential to gorilla conservation. Given the challenges of protecting habitat in countries ravaged by civil war, where human populations often live in substandard conditions, with few if any government services, and law enforcement is limited, the international community will have to support conservation efforts (Plumptre et al. 2003). Integrated conservation and development programs may be useful tools in areas where human suffering leads to loss of biodiversity and international aid organizations must be willing to create projects that provide opportunities for people without sacrificing the integrity of conservation goals. Maintaining corridors of habitat between fragments of forest in which the least numerate subspecies exist as well as strict protection of these areas from poachers and encroachment by human populations will help bolster gene flow (Oates et al. 2003).

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Threat: Human Disturbance

War and civil unrest are indisputable causes of loss of biodiversity in Africa. Well armed insurgents seek refuge in forests, move between borders, set up camps and kill gorillas for subsistence usage or sport. Moreover, masses of displaced people seek food and shelter as they flee from violent conflict. This has resulted in large tracts of land being cleared for fuelwood, hunting of gorillas for food, and transmission of disease between humans and gorillas. While the extent of the damage following conflict is largely unknown, there are undoubtedly negative impacts on all subspecies of gorillas (Vedder et al. 2001; Plumptre et al. 2003).

Potential solutions

By looking at historical patterns of warfare and civil unrest, much can be learned about potential future threats to gorillas. For example, parks and reserves on country borders are extremely susceptible to becoming zones of military operations, park staff and their families are at very high risk if they remain to carry on their duties, and international monetary support is likely to dissipate as conflict heightens (Vedder et al. 2001). There are some positive lessons learned as well, though. Where ecotourist activities are important, less damage is likely to occur, in areas of long-term research and commitment, fewer losses are incurred, and the support and commitment of junior staff should not be underestimated (Vedder et al. 2001). While there are seemingly few solutions to the deep-rooted tensions in the region, conservationists should remain hopeful that the capacity for recovery, of both people and wildlife, is great and cannot be underestimated.

LINKS TO MORE ABOUT CONSERVATION

CONSERVATION INFORMATION

• African Great Apes  (link broken) (WWF African Great Apes Programme, January 2005)
• Best Practice Guidelines for Great Ape Tourism  (by Elizabeth J. Macfie and Elizabeth A. Williamson with contributions from Marc Ancrenaz, Chloe Cipolletta, Debby Cox, Christina Ellis, David Greer, Chloe Hodgkinson, Anne Russon and Ian Singleton; IUCN Primate Specialist Group; 2010; PDF)
• Best Practice Guidelines for Mitigating Human – Great Ape Conflict  (IUCN; 2009)
• Best Practice Guidelines for Surveys and Monitoring of Great Ape Populations  (IUCN/SSC Primate Specialist Group; 2008)
• Best Practice Guidelines for the Re-introduction of Great Apes  (IUCN/SSC Primate Specialist Group)
• Best Practice Guidelines to Reduce the Impact of Logging  (IUCN/SSC Primate Specialist Group, 2007)
• Best Practices for Great Ape Conservation  (IUCN/SSC Primate Specialist Group; 2009)
• Central African Gorilla Habitat  (Satellite view)
• Congo Gorilla Forest: Gorilla Conservation (link broken)
• Gorilla Help Site
• Gorillas in the Soup
• GRASP: Great Apes Survival Project (link broken)
• Great Apes and FSC: Implementing ‘Ape Friendly’ Practices in Central Africa’s Logging Concessions (link broken) (IUCN; 2013; PDF)
• Mountain Gorilla Protection: A Geomatics Approach (link broken)
• Port Lympne’s gorilla Djala and family join wild primates in Gabon  (BBC; June 24, 2014)
• Slaughter of the Apes  (October 13, 2006)
• Tracking Mountain Gorillas in Uganda  (Wall Street Journal; June 7, 2013)
• Links for all species

CONSERVATION NEWS

• How Will Climate Change Affect Mountain Gorillas?  (Scientific American; October 1, 2013)
• Congo’s rare mountain gorillas could become victims of oil exploration  (The Guardian; August 1, 2013)
• Saving the Gorillas and Launching a Nation’s Tourism Economy  (The Atlantic; August 1, 2013)
• New conservation complex will protect critically endangered gorillas  (Environment News Network; July 9, 2013)
• Port Lympne’s gorilla Djala returned to Gabon with family  (BBC News; June 24, 2013)
• World Heritage Body Wants Drilling Ban in Gorilla Sanctuary  (Environment News Service; June 17, 2013)
• Eating this exotic meat may seriously damage your health  (The Independent; June 16, 2013)
• A return to childhood: seeking African gorillas at Volcanoes Natl Park (link broken) (Washington Times; March 15, 2013)
• Gorillas in our midst  (Yorkshire Post; May 20, 2013)
• Great Apes in Crisis: Thousands Poached and Stolen from the Wild Annually  (Scientific American; March 7, 2013)
• Gorillas Caught in the Crossfire in the Democratic Republic of Congo  (ScienceDaily; March 13, 2013)
• Great Apes in Crisis: Thousands Poached and Stolen from the Wild Annually  (Scientific American; March 7, 2013)
• Lowland Gorillas, Protected in a Green Abyss (link broken)  (New York Times; January 31, 2013)
• New Park Protects 15,000 Gorillas  (ScienceDaily; January 31, 2013)
• The Congo: Gorillas in the wild  (Telegraph; January 16, 2013)
• The Perils and Rewards of Protecting Congo’s Gorillas  (Yale Environment 360; January 8, 2013)
• Primatologist warns of possible great ape extinction  (CBC News; December 14, 2012)
• Endangered primates caught in Congolese conflict  (NewScientist; November 28, 2012)
• Young Gorillas Outwit Poachers  (Audubon Magazine; November 28, 2012)
• Protected Mountain Gorilla Population Rises by Ten Percent in Two Years  (Smithsonian; November 15, 2012)
• The betrayal of John Kahekwa: how Britain let down an inspirational conservationist from Congo  (The Independent; October 31, 2012)
• Family of gorillas to be released in Gabon by Aspinall Foundation (link broken) (Kent Online; October 24, 2012)
• Can Ecotourism Save the Great Apes?  (Harvard University Press Blog ; October 22, 2012)
• Congolese rebels cash in on gorilla tourism to fund insurgency  (Guardian; October 19, 2012)
• Gamble in the jungle (need subscription?) (Financial Times; October 19, 2012)
• Great ape habitat in Africa has dramatically declined (link broken) (BBC; September 28, 2021)
• Dwindling space for Africa’s great apes  (Physorg; September 26, 2012)
• In the midst of gorillas (link broken) (Sydney Morning Herald; September 18, 2012)
• An ape-y ending: Gorilla families missing for three months found alive after warring factions let rangers into Congo forest  (Daily Mail; August 3, 2012)
• Fighters agree to gorilla survey in Virunga  (BBC News; July 24, 2012)
• Due piccoli gorilla distruggono le trappole dei bracconieri (link broken) (National Geographic Italia; July 23, 2012; in Italian)
• Young Mountain Gorillas Observed Destroying Poachers’ Snares for the First Time  (WebWire; July 17, 2012)
• How to Greet a Mountain Gorilla  (Time; June 6, 2012)
• Cross River Gorillas: Footage of Rare Apes Captured in Cameroon  (ABC News; May 9, 2012)
• Saving the Cross River Gorilla (link broken) (Voice of America; March 20, 2012)
• Ted Turner donates $1M to save gorillas (link broken) (Miami Herald; March 19, 2012)
• Researchers examine consequences of non-intervention for infectious disease in African great apes  (EurekAlert; February 6, 2012)
• Satellite study reveals critical habitat and corridors for world’s rarest gorilla  (EurekAlert; January 31, 2012)
• Gorilla trek  (Los Angeles Times; November 17, 2011)
• Trek of a Lifetime: Encountering Rwanda’s Gorillas Up Close (link broken) (Time; October 11, 2011)
• Baby gorilla on black market for $40,000 is rescued  (MSNBC; October 11, 2011)
• Gorilla poachers brutally murder forest ranger  (Mongabay; October 9, 2011)
• Corning Donates $25,000 to the Dian Fossey Gorilla Fund International (link broken) (MarketWatch; October 3, 2011)
• Mountain Gorilla Census On in Country  (The Monitor; October 3, 2011)
• Uganda: mountain gorillas and Batwa pygmies in Bwindi Impenetrable National Park  (Telegraph; September 29, 2011)
• Mountain Gorillas: The Rules of Engagement  (Mother Jones; September 9, 2011)
• Six Gorillas Repatriated  (allAfrica.com; August 18, 2011)
• Rwanda’s Post-Civil War Hope? Gorilla Tourism (link broken) (Time; July 21, 2011)
• Sick Leave  (Conservation Magazine; June 1, 2011)
• There’s no magic number for saving endangered species  (EurekAlert; May 16, 2011)
• Gorilla Haven Found in Cameroon (link broken) (Discovery News; March 28, 2011)
• Chimpanzee and gorilla heads seized in Gabon  (BBC News; January 20, 2011)
• Primatologists: the best hope for apes is the best hope for us  (Mongabay; December 15, 2010)
• Mountain gorilla population grows: census (link broken) (AFP; December 7, 2010)
• Going Ape in Central Africa: Meeting Our Closest Cousins in the Near-Wild Within Easy Reach of Major Cities  (Huffington Post; October 12, 2010)
• Interaction with rare mountain gorillas of Rwanda  (Economic Times; September 9, 2010)
• Gorillas Fight for Survival  (East African Business Week ; August 9, 2010)
• Meeting, and Counting, Mountain Gorillas  (New York Times; July 29, 2010)
• British researchers call for strict changes on gorilla tourism (link broken) (Rwanda News Agency; June 17, 2010)
• RDB Intensifies Gorilla Monitoring  (Rwanda New Times; May 25, 2010)
• Damian Aspinall Gorilla Reunion (link broken) (Post Chronicle; May 17, 2010)
• Gorillas suffer as eco-tourists get too close, warn researchers  (Guardian; May 16, 2010)
• iPhone app to help DR Congo mountain gorillas  (BBC News; May 17, 2010)
• Eugene Ratagarama: Rwanda’s conservation king  (CNN; May 12, 2010)
• Mountain Gorilla Census, 2010  (Rwanda New Times; May 10, 2010)
• UN peacekeepers stage great ape escape in Congo  (New Scientist; May 4, 2010)
• Snails Are Saving Endangered Gorillas (link broken) (Discovery News; April 28, 2010)
• Gorillas could vanish from Congo by 2025  (UPI; March 25, 2010)
• New hope for mountain gorillas in Congo  (Guardian; March 8, 2010)
• In search of world’s rarest and most endangered gorilla  (CNN; February 25, 2010)
• Census of Mountain Gorillas Begins Next Month  (New Times; February 10, 2010)
• Another Gorilla Group Prepared for Tourism  (New Vision; January 26, 2010)
• World Wildlife Fund lists the 10 most threatened species in 2010  (Washington Post; January 20, 2010)
• Gorillas: still wild at heart  (The Independent; December 21, 2009)
• Charcoal trade threatens gorillas  (UPI; December 12, 2009)
• A year after discovery, Congo’s ‘mother lode’ of gorillas remains vulnerable  (EurekAlert; November 23, 2009)
• Wildlife expert claims gorilla dung is critical to containing climate change  (Guardian; October 13, 2009)
• Scientists: Aggressive Poaching Could Wipe Out Gorilla Population in Areas of Congo (link broken) (Fox News; September 17, 2009)
• Uganda offers Facebook scheme to ‘befriend’ gorillas (link broken) (AFP; August 31, 2009)
• Gorillas orphaned by bushmeat trade set free on island  (Mongabay; August 10, 2009)
• Devastating death of a silverback at Mount Tshiaberimu (link broken) (The Gorilla Organization; July 15, 2009)
• The Impact of Congo Violence on Lowland Gorillas  (Scientific American; July 23, 2009)
• Wildfires threaten endangered gorilla habitat in central Africa  (Telegraph; July 20, 2009)
• Gorilla medicine (link broken) (Baltimore Sun; July 5, 2009)
• Conservationists Lobby for Gorilla Protection  (New Times, Rwanda; June 18, 2009)
• Governments at UN-backed forum issue appeal to save gorillas  (UN News Centre; June 11, 2009)
• Range extended for world’s most mysterious gorilla  (Mongabay; June 11, 2009)
• Gorilla warfare in the Congo jungle  (Telegraph; May 27, 2009)
• In the Jungle With the Gorilla Whisperer  (ABC News; May 4, 2009)
• The last mountain gorillas, and their protectors  (Christian Science Monitor; May 4, 2009)
• More than 300 gorillas butchered each year in the Republic of Congo  (Mongabay; March 27, 2009)
• Best Practice Guidelines to Reduce the Impact of Logging  (IUCN/SSC Primate Specialist Group; 2007)
• Congo park reports 10 gorillas born in 16 months (link broken) (Associated Press; January 26, 2009)
• DNA tests suggest mountain gorilla population ‘shrunk’  (Telegraph, UK; January 21, 2009)
• Gorillas In Their Midst (link broken) (The American; December 31, 2008)
• Gorilla states in poaching pledge  (BBC News; December 5, 2008)
• Rare gorilla twins born in Uganda (link broken) (AFP; December 3, 2008)
• Congo’s war – baby gorillas bring hope for endangered species (link broken) (AFP; November 30, 2008)
• UN officials launch “Year of the Gorilla”(link broken)  (Associated Press; December 1, 2008)
• Park rangers returning to gorilla refuge  (CNN; November 21, 2008)
• Congo Violence Reaches Endangered Mountain Gorillas  (New York Times; November 17, 2008)
• Guerillas threaten gorillas in Africa’s oldest national park (link broken) (AFP; November 16, 2008)
• Thousands flee fighting as Congo rebels seize gorilla park  (CNN; October 26, 2008)
• Uganda wildlife park gets new gorilla family (link broken) (AFP; October 3, 2008)
• Uganda to prepare more mountain gorillas for contact with humans (link broken) (Vancouver Sun; September 18, 2008)
• Diary: Protecting mountain gorillas  (BBC News; August 26, 2008)
• Man Suffers from 1,415 Diseases; Blames His Gorilla Meat Diet (link broken) (EcoWorldly)
• Belgian Named New Warden of Troubled Gorilla Park (link broken) (National Geographic News; August 7, 2008)
• United States to Support Mountain Gorilla Conservation  (Kigali New Times; July 15, 2008)
• More than 100,000 rare gorillas found in Congo  (CNN; August 5, 2008)
• Gorillas hand-reared in Kent returned to wild in Africa  (Telegraph; July 28, 2008)
• Fatal Attack on Conservationists’ Truck in Gorilla Park (link broken) (National Geographic News; July 11, 2008)
• Gorillas: In their midst at Volcanoes National Park (link broken) (Associated Press; July 8, 2008)
• Cameroon: Towards a new park in West (link broken) (Africa News; July 7, 2008)
• Travelers Meet Apes In the Rwandan Jungle (link broken) (ABC News; July 4, 2008)
• Gorillas: 20, Humans: $25,000  (Huffington Post; June 26, 2008)
• “Gorilla Guy” raises $30,000 for primates (link broken) (Seattle Times; June 24, 2008)
• Brent Stirton, Chronicling the Virunga Gorilla Murders  (NPR; June 24, 2008)
• Inside the Gorilla Wars: Rangers on Risking It All (link broken) (National Geographic News; June 16, 2008)
• National Geographic Channel Presents Exclusive Coverage of the Gorilla Massacre in Virunga National Park That Horrified the World (link broken) (Digital Producer Magazine; July 1, 2008)
• Gorillas in our midst (link broken) (News.com.au, Australia; May 12, 2008)
• World’s rarest gorilla gets its own forest reserve (link broken) (Mongabay; April 18, 2008)
• World’s Rarest Gorillas Gain New Refuge (link broken) (National Geographic News; April 22, 2008)
• Saving Country’s Endangered Apes From Extinction  (Kampala Monitor; April 23, 2008)
• Ebola Virus Threatens Gorilla With Extinction (link broken) (Fox News; April 17, 2008)
• Congo gorilla murder charges (link broken) (Melbourne Herald Sun; March 21, 2008)
• Rwanda’s silverback gorilla lodge (link broken) (Times Online; March 16, 2008)
• Gorilla rangers execution threat  (BBC News; March 7, 2008)
• Sigourney Weaver returns to scene of Gorillas in the Mist  (Melbourne Herald Sun; March 5, 2008)
• Three countries in pact to save mountain gorillas  (Guardian Unlimited; February 21, 2008)
• The world of mountain gorillas  (BBC News; January 25, 2008)
• Congo gorillas in the midst of a war zone  (San Francisco Chronicle; January 20, 2008)
• Rangers and gorillas of Congo sanctuary are thrust onto front lines of war  (Associated Press; January 13, 2008)
• Rwanda introduces ‘gorilla tax’  (AFP; December 24, 2007)
• Anderson Cooper: Gorillas in midst of murder  (CNN; December 14, 2007)
• Gorillas Prepare to Fly to Cameroon  (Associated Press; November 29, 2007)
• Diary: Protecting mountain gorillas  (BBC News; November 26, 2007)
• By saving gorillas, can Congolese save themselves?  (Reuters; November 5, 2007)
• Rare Gorillas at Risk as Rebels Seize Congo Park  (National Geographic News; October 11, 2007)
• More mountain gorillas for tourists  (Reuters; October 9, 2007)
• Rebels overrun gorilla hideouts  (Independent Online; October 8, 2007)
• Congo rangers break suspected gorilla traffic ring  (Reuters; September 25, 2007)
• Dian Fossey Fund Expands to Help Save Congo Mountain Gorillas  (E-Wire; September 21, 2007)
• Best Practice Guidelines for the Re-introduction of Great Apes  (IUCN/SSC Primate Specialist Group)
• Congo rebels seize gorilla park  (BBC News; September 4, 2007)
• Gorillas abandoned as renegade Congolese fight government in nature reserve  (Daily Mail; September 4, 2007)
• Emergency Gorilla-Protection Force Deployed in Congo (link broken) (National Geographic News; August 21, 2007)
• Mountain gorilla born in DRC (link broken) (Independent Online; August 22, 2007)
• Remains of Fifth Rare Gorilla Discovered Following Congo Attack (link broken) (Voice of America; August 20, 2007)
• Gorillas’ Safety Vital to Africa’s Tourism Market  (ABC News; August 8, 2007)
• Rare gorillas slaughtered in mass killing (link broken) (Mongabay; July 24, 2007)
• Gorillas in the fog for conservation (link broken) (San Francisco Chronicle; June 11, 2007)
• DR Congo rebel threat to gorillas  (BBC News; May 21, 2007)
• Gorillas she missed  (The Age, Australia; April 26, 2007)
• Mountain gorillas on the rise – WWF (link broken) (Independent Online; April 20, 2007)
• Rare gorillas habituated to boost tourism (link broken) (Independent Online; March 12, 2007)
• Web charity helps save Congo’s gorillas  (USA Today; March 12, 2007)
• Helping a species survive (link broken) (Cleveland News-Herald; March 8, 2007)
• Ceasefire, donations helping Congo apes (link broken) (ScienceDaily; March 5, 2007)
• Saving Gabon’s orphan gorillas  (BBC News; March 1, 2007)
• Gorillas (and chimps) in their midst (link broken) (Roanoke Times; February 2, 2007)
• Rebels agree to stop gorilla killings (link broken) (Independent Online; January 28, 2007)
• Congo rebels kill rare ape, raising survival fears (link broken) (Reuters; January 10, 2007)
• Trust’s donations save apes worldwide (link broken) (Des Moines Register; December 15, 2006)
• Gorilla conservation project takes ‘one-health’ approach (link broken) (JAVMA News; November 15, 2006)
• Road kill in Cameroon – killing of gorillas and other animals (link broken) (Natural History; February 1997)
• 2050 could mean the end for gorillas (link broken) (Independent Online; July 30, 2006)
• Greatest ape extinct within decades – UN (link broken) (Independent Online; July 17, 2006)
• Village has a gorilla economy  (San Francisco Chronicle; July 16, 2006)
• How gorillas survived a war (link broken) (Seattle Times; June 22, 2006)
• Gorilla numbers have increased (link broken) (New Vision, Uganda; June 13, 2006)
• Bwindi gorillas get babies (link broken) (New Vision, Uganda; May 31, 2006)
• Florida College Students Helping to Save Dian Fossey’s Gorillas (link broken) (eMediaWire; May 12, 2006)
• UN hails Uganda on gorillas (link broken) (New Vision, Uganda; March 21, 2006)
• Gorillas in Rwanda  (Washington Post; March 5, 2006)
• Mountain Gorilla Survival Appeal (link broken) (Australasian Primate Society)
• Congolese man protects endangered gorillas  (USA Today; November 18, 2005)
• How Cell Phones Are Killing Off Gorillas (link broken) (KFMB-TV, San Diego; November 9, 2005)
• Bush-meat traders threaten Nigeria’s chimps (link broken) (Georgia Straight, Canada; November 3, 2005)
• Founder of Eastern Congo Gorilla Reserve wins award (link broken) (Happy News.com; October 20, 2005)
• Woods Hole Research Center scientist part of international initiatives to save the great apes  (EurekAlert; October 11, 2005)
• Dian Fossey Gorilla Fund International Reports Gorillas in Eastern Congo More Numerous Than Expected (link broken) (PR Newswire; September 27, 2005)
• Guerrillas threaten gorillas in volatile DRC (link broken) (Independent Online, South Africa; September 8, 2005)
• Apes ‘extinct in a generation’  (BBC News; September 1, 2005)
• Gorillas being poached for ‘bushmeat’ trade (link broken) (Independent Online, South Africa; August 31, 2005)
• Poaching, Logging Ebola Threaten Gorillas and Chimps  (Newswise; August 30, 2005)
• Conservationists seek to protect apes (link broken) (Associated Press; July 27, 2005)
• Gorilla adoption a unique marketing tool (link broken) (Independent Online, South Africa; June 28, 2005)
• DRC soldiers ‘killing gorillas’ (link broken) (News 24, South Africa; June 22, 2005)
• Satellite maps will ease plight of endangered mountain gorillas  (European Space Agency; April 8, 2005)
• Desperate plight of the great apes (link broken) (Australian Broadcasting Company; March 11, 2005)
• Expert highlights mobile phone threat to great apes  (Australian Broadcasting Company; March 10, 2005)
• Study links Ebola outbreaks to animal carcasses  (EurekAlert; February 14, 2005)
• Gorillas in Peril (link broken) (LiveScience.com; January 27, 2005)
• Rare gorillas beat the odds in DRC forests (link broken) (Independent Online, South Africa; January 28, 2005)
• Bushmeat trade threatens wildlife and humans (link broken) (Concord Monitor; January 21, 2005)
• Gorillas are missed in the DRC (link broken) (Independent Online, South Africa; December 29, 2004)
• Gorillas in the Midst of Extinction  (NASA; January 6, 2005)
• Uganda’s poor hope for more gorilla dollars  (BBC News; May 21, 2004)
• The illegal trade in gorillas  (The Economist; November 4, 2004)
• Eastern Lowland Gorilla Numbers Plunge to 5,000, Study Says (link broken) (National Geographic News; March 31, 2004)
• Aids warning over bushmeat trade  (BBC News; October 26, 2004)
• Primate Viruses Transmitted To People Through Bushmeat  (ScienceDaily; March 19, 2004)
• Learning to Track Like a Bushman  (Wired; January 22, 2004)
• The Garden Of Eden  (CBS News; February 23, 2004)
• Catastrophic loss of wild bamboo threatens pandas, mountain gorillas — UN  (UN News Centre; May 11, 2004)
• Fences ‘can help apes’ survival’  (BBC News; May 5, 2004)
• The fight to save the eastern lowland gorilla  (CNN; May 17, 2004)
• African apes being eaten into extinction (link broken) (Sunday Herald, UK; October 11, 2003)
• African `bushmeat’ trade raises health, conservation fears  (Taipei Times; August 25, 2003)
• Countries find common ground to protect world’s rarest gorilla  (EurekAlert; September 17, 2003)
• Dire Outlook for Many Primates  (BBC; May 12, 2000)
• Eating apes imperils species, spreads AIDS  (ABC Science Online, Australia; September 15, 2003)
• Extinction looms over mountain gorilla (link broken) (Independent; October 17, 2002)
• Gorilla Wild: Face-to-Face in Africa for a New TV Film (link broken) (National Geographic News; August 15, 2003)
• Gorillas in our midst (link broken) (St. Petersburg Times; November 17, 2002)
• Gorillas make home in ‘impenetrable’ forest (link broken) (National Geographic News; March 8, 2001)
• Gorillas’ friend wins global award  (BBC News; April 23, 2001)
• Great apes in peril  (BBC News; May 20, 2001)
• Growing demand for ‘bushmeat’ threatens great apes  (CNN; August 11, 1999)
• Hopes rise for mountain gorillas  (BBC News; October 17, 2002)
• Last chance to save great apes from extinction  (Guardian Unlimited; May 21, 2001)
• Massive Die-Off of Great Apes Reported in Africa (link broken) (National Geographic News; February 6, 2003)
• Orphans of the Slaughter (link broken) (Toledo Blade; December 10, 2000)
• Poaching for baby gorillas turns deadly  (CNN; November 30, 2002)
• Space Age Plan to Save Gorillas (BBC, October 3, 2001)  (BBC; October 3, 2001)
• Links for all species

ORGANIZATIONS INVOLVED IN Gorilla CONSERVATION

• African Conservation Foundation
• African Wildlife Foundation
• Dian Fossey Gorilla Fund International
• International Gorilla Conservation Programme
• Jane Goodall Institute France
• Limbe Wildlife Centre
• Projet Protection des Gorilles

Content last modified: October 4, 2005

Written by Kristina Cawthon Lang. Reviewed by Tara Stoinski.

Cite this page as: Cawthon Lang KA. 2005 October 4. Primate Factsheets: Gorilla (Gorilla) Conservation . <http://pin.primate.wisc.edu/factsheets/entry/gorilla/cons>. Accessed 2020 July 22.

The following references were used in the writing of this factsheet. To find current references for Gorilla, search PrimateLit.

REFERENCES

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Western lowland gorilla diet and resource availability: new evidence, cross-site comparisons, and reflections on indirect sampling methods. Am J Primatol 58: 91-116. Fay JM, Carroll R, Kerbis Peterhans JC, Harris D. 1995. Leopard attack on and consumption of gorillas in the Central African Republic. J Hum Evol 29(1): 93-9. Fletcher A. 2001. Development of infant independence from the mother in wild mountain gorillas. In: Robbins MM, Sicotte P, Stewart KJ, editors. Mountain gorillas: three decades of research at Karisoke. Cambridge (England): Cambridge University Press. p 153-82. Fossey D. 1972. Vocalizations of the mountain gorilla (Gorilla gorilla beringei). Anim Beh 20: 36-53. Goodall J, Fouts R, Patterson F, Katz E, Bekoff M, Galdikas B, editors. 2003. The great ape project census: recognition for the uncounted. Portland (OR): Great Ape Project. 268 p. Groves C. 2001. Primate taxonomy. Washington DC: Smithsonian Inst Pr. 350 p. Hall JS, Saltonstall K, Inogwabini BI, Omari I. 1998. Distribution, abundance and conservation status of Grauer’s gorilla. Oryx 32(2): 122-30. Harcourt AH. 2003. An introductory perspective: gorilla conservation. In: Taylor AB, Goldsmith ML, editors. Gorilla biology: a multidisciplinary perspective. Cambridge (England): Cambridge Univ Pr. p 407-13. Hart JA, Hall JS. 1996. Status of eastern Zaire’s forest parks and reserves. Cons Bio 10(2): 316-27. Harcourt AH, Stewart KJ, Hauser M. 1993. Functions of wild gorilla “close” calls. I. Repertoire, context, and interspecific comparison. Behaviour 124(1/2): 89-122. Ilambu O. 2001. Ecology of eastern lowland gorilla: is there enough scientific knowledge to mitigate conservation threats associated with extreme disturbances in its distribution range? In: The apes: challenges for the 21^st century. Conference proceedings; 2000 May 10-13; Brookfield, IL. Chicago: Chicago Zoo Soc. p 307-12. Kuroda S, Nishihara T, Susuki S, Oko RA. 1996. Sympatric chimpanzees and gorillas in the Ndoki Forest, Congo. In: McGrew WC, Marchant LF, Nishida T, editors. Great ape societies. Cambridge (England): Cambridge Univ Pr. p 71-81. Leigh SR, Relethford JH, Park PB, Konigsberg LW. 2003. Morphological differentiation of Gorilla subspecies. In: Taylor AB, Goldsmith ML, editors. Gorilla biology: a multidisciplinary perspective. Cambridge (England): Cambridge Univ Pr. p 104-31. Magliocca F, Querouil S, Galutier-Hion A. 1999. Population structure and group composition of western lowland gorillas in the north-western Republic of Congo. Am J Primatol 48: 1-14. McNeilage A. 2001. Diet and habitat use of two mountain gorilla groups in contrasting habitats in the Virungas. In: Robbins MM, Sicotte P, Stewart KJ, editors. Mountain gorillas: three decades of research at Karisoke. Cambridge (England): Cambridge University Press. p 265-92. Mittermeier RA, Konstant WR, Rylands AB, Ganzhorn J, Oates JF, Butynski TM, Nadler T, Supriatna J, Padu CV, Rambaldi D, contributors. Primates in Peril: the world’s 25 most endangered primates. Washington DC: Conservation Intl. 19 p. Mudakikwa AB, Cranfield MR, Sleeman JM, Eilenberger U. 2001. Clinical medicine, preventive health care and research on mountain gorillas in the Virunga Volcanoes region. In: Robbins MM, Sicotte P, Stewart KJ, editors. Mountain gorillas: three decades of research at Karisoke. Cambridge (England): Cambridge University Press. p 341-60. Nowak RM. 1999. Walker’s primates of the world. Baltimore: Johns Hopkins Univ Pr. 224 p. Oates JF, compiler. 1995. Status survey and conservation action plan: African primates (Revised edition). Gland (Switzerland): IUCN/SSC Primate Specialist Group. 80 p. Oates JF, McFarland KL, Groves JL, Bergl RA, Linder JM, Disotell TR. 2003. The Cross River gorilla: natural history and status of a neglected and critically endangered subspecies. In: Taylor AB, Goldsmith ML, editors. Gorilla biology: a multidisciplinary perspective. Cambridge (England): Cambridge Univ Pr. p 472- 97. Parnell RJ. 2002. Groups size and structure in western lowland gorillas (Gorilla gorilla gorilla) at Mbeli Bai, Republic of Congo. Am J Primatol 56: 193-206. Patterson FGP, Gordon W. 2001. Twenty-seven years of project Koko and Michael. In: Galdikas BMF, Erickson Briggs N, Sheeran LK, Shapiro GL, Goodall J, editors. All apes great and small. Volume 1, African apes. New York: Kluwer Acadmemic/Plenum. p 165-76. Plumptre AJ, McNeilage A, Hall JS, Williamson EA. 2003. The current status of gorillas and threats to their existence at the beginning of a new millennium. In: Taylor AB, Goldsmith ML, editors. Gorilla biology: a multidisciplinary perspective. Cambridge (England): Cambridge Univ Pr. p 414- 31. Poulsen JR, Clark CJ. 2004. Densities, distributions, and seasonal movements of gorillas and chimpanzees in swamp forest in northern Congo. Int J Primatol 25(2): 285-306. Robbins MM. 2001. Variation in the social system of mountain gorillas: the male perspective. In: Robbins MM, Sicotte P, Stewart KJ, editors. Mountain gorillas: three decades of research at Karisoke. Cambridge (England): Cambridge Univ Pr. p 29-58. Robbins MM, McNeilage A. 2003. Home range and frugivory patterns of mountain gorillas in Bwindi Impenetrable National Park, Uganda. Int J Primatol 24(3): 467-91. Rowe N. 1996. Pictorial guide to the living primates. East Hampton (NY): Pogonias Pr. 263 p. Sarmiento EE. 2003. Distribution, taxonomy, genetics, ecology, and causal links of gorilla survival: the need to develop practical knowledge for gorilla conservation. In: Taylor AB, Goldsmith ML, editors. Gorilla biology: a multidisciplinary perspective. Cambridge (England): Cambridge Univ Pr. p 432-71. Sicotte P. 2001. Female mate choice in mountain gorillas. In: Robbins MM, Sicotte P, Stewart KJ, editors. Mountain gorillas: three decades of research at Karisoke. 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Gorilla social relationships: a comparative review. In: Taylor AB, Goldsmith ML, editors. Gorilla biology: a multidisciplinary perspective. Cambridge (England): Cambridge Univ Pr. p 302-27. White LJT, Tutin CEG. Why chimpanzees and gorillas respond differently to logging: a cautionary tale from Gabon. In: Weber W, White LJT, Vedder A, Naughton-Treves L, editors. African rain forest ecology and conservation: an interdisciplinary perspective. New Haven (CT): Yale Univ Pr. p 449-62. Wilkie DS, Carpenter JF. 2001. Bushmeat hunting in the Congo Basin: an assessment of impacts and options for mitigation. In: The apes: challenges for the 21^st century. Conference proceedings; 2000 May 10-13; Brookfield, IL. Chicago: Chicago Zoo Soc. p 212-26. Yamagiwa J, Kahekwa J. 2001. Dispersal patterns, group structure, and reproductive parameters of eastern lowland gorillas at Kahuzi in the absence of infanticide. In: Robbins MM, Sicotte P, Stewart KJ, editors. Mountain gorillas: three decades of research at Karisoke. Cambridge (England): Cambridge Univ Pr. p 89-122. Yamagiwa J, Kahekwa J, Kanyunyi Basabose A. 2003. Intra-specific variation in social organization of gorillas: implications for their social evolution. Primates 44: 359-69. Yamagiwa J, Maruhashi T, Yumoto T, Mwanza N. 1996. Dietary and ranging overlap in sympatric gorillas and chimpanzees in Kahuzi-Biega National Park, Zaire. In: McGrew WC, Marchant LF, Nishida T, editors. Great ape societies. Cambridge (England): Cambridge Univ Pr. p 82-98. Yamagiwa J, Mwanza N, Yumoto T, Maruhashi T. 1994. Seasonal change in the composition of the diet of eastern lowland gorillas. Primates 35(1): 1-14.

Content last modified: October 4, 2005

AUDIO

• Gorilla gorilla beringei: Belch  (African Primates at Home/Indiana University)
• Gorilla gorilla beringei: Chest-beat  (African Primates at Home/Indiana University)
• Gorilla gorilla beringei: Grunts, chestbeating  (Wild Sanctuary)

VIDEO & WEBCAMS

• Gorilla iCam  (Gorilla World at the Cincinnati Zoo & Botanical Garden)
• Gorilla Introductions – Cincinnati Zoo  (1:27, narrated; Gorilla World at the Cincinnati Zoo & Botanical Garden; Flash/YouTube)
• Gorilla Rescue  (3:40, narrated; National Geographic Kids; Flash)
• Gorillas – Cincinnati Zoo  (0:57; Gorilla World at the Cincinnati Zoo & Botanical Garden; Flash/YouTube)
• Nature: A Conversation with Koko  (:25, narrated)

IMAGES

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	Gorilla Photo: Primates in Art & Illustration Collection
	Gorilla beringei beringei Photo: A. W. Weber and A. Vedder
	Gorilla beringei beringei Photo: A. W. Weber and A. Vedder
	Gorilla beringei beringei Photo: A. W. Weber and A. Vedder
	Gorilla beringei beringei Photo: A. W. Weber and A. Vedder
	Gorilla beringei beringei Photo: A. W. Weber and A. Vedder
	Gorilla beringei beringei Photo: A. W. Weber and A. Vedder
	Gorilla beringei beringei Photo: A. W. Weber and A. Vedder
	Gorilla beringei beringei Photo: A. W. Weber and A. Vedder
	Gorilla beringei beringei Photo: A. W. Weber and A. Vedder
	Gorilla beringei beringei Photo: A. W. Weber and A. Vedder
	Gorilla beringei beringei Photo: A. W. Weber and A. Vedder
	Gorilla beringei graueri Photo: Rick Murphy
	Gorilla gorilla gorilla Photo: Bryan Lenz
	Gorilla gorilla gorilla Photo: Bryan Lenz
	Gorilla gorilla gorilla Photo: Helen Buckland
	Gorilla gorilla gorilla Photo: Helen Buckland
	Gorilla gorilla gorilla Photo: Irwin S. Bernstein
	Gorilla gorilla gorilla Photo: Rick Murphy
	Gorilla gorilla gorilla Photo: Rick Murphy
	Gorilla gorilla gorilla Photo: Rick Murphy
	Gorilla gorilla gorilla Photo: Rick Murphy
	Gorilla gorilla gorilla Photo: Steve Ross