Gorilla Numbers

Before conservation measures for a gorilla population can be planned, their numbers and their exact distribution area have to be known. For this purpose, a Census is made. In general, survey teams walk along pre-determined straight lines (so-called transects) and note all gorilla traces they see. On this basis the distribution area is drawn and population numbers are calculated, and this allows experts to decide whether conservation measures are necessary and which ones are most urgent.

In mountain gorillas the situation is different: as their distribution is well known, Gorilla Groups are counted individually. If possible, such censuses are done every 5 years to track the development of the population.

Gorilla Numbers

Numbers of gorillas in various populations
The numbers of most populations are not known, and it is very difficult to give valid numbers. Recently, the number of gorillas has been cut severely by bushmeat hunting and Ebola. All gorilla species and subspecies are endangered or critically endangered according to the IUCN Red Data List.

Ranges of Western Lowland Gorillas

Western lowland gorilla ranges are in general larger than those of mountain gorillas - this has been the general opinion among researchers for a long…

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Gorillas, Chimpanzees and Forest Elephants Thrive in the Rio Campo Nature Reserve

Protected areas aim to conserve wildlife - particularly large, charismatic species like gorillas - while benefiting local communities. But in tropical…

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The Kansere-Masakaru-Iyuma Forests in Utunda-Nord

The Kansere-Masakaru-Iyuma forests are located between the Usala Gorilla Reserve (RGU) and the Kisimba-Ikobo Primate Reserve (RPKI), in the vicinity…

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Mountain Gorilla Population Growth

New research from the Dian Fossey Gorilla Fund analyses more than 50 years of demographic data to examine factors influencing variability in the…

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Are Mountain Gorillas still "Wild"?

Everywhere in Africa human influence on gorillas and their habitats has become common. Interventions are severe everywhere, not only by deforestation,…

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Distribution and Habitat Use of Gorillas in the Ebo Forest

Although gorilla distribution and habitat use are fairly well known for many gorilla populations in Cameroon, very little is known concerning the Ebo…

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Two Infants within Two Years at Mount Tshiaberimu

Mount Tshiaberimu (or Tshiabirimu) is located in the southern part of the Northern Sector of Virunga National Park. At the beginning of January 2020,…

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Nkuba: a Community Reserve in Eastern D. R. Congo

In 2012, the Dian Fossey Gorilla Fund International started a unique collaboration with local communities in eastern Democratic Republic of the Congo…

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Photos of Hope from Tayna Nature Reserve

In last December’s issue of the Gorilla Journal, the Gorilla Rehabilitation and Conservation Education (GRACE) Center was thrilled to share our…

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Great Ape Survey in Tayna Nature Reserve

In 2021, GRACE completed the first-ever great ape survey of the entire Tayna Nature Reserve, in eastern Democratic Republic of the Congo (DRC). How…

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New Grauer's Gorilla Population Estimate

A recent paper in the American Journal of Primatology by Andrew Plumptre and colleagues examined the largest survey dataset for Grauer's gorillas Gori…

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Gorilla Baby Boom in Bwindi?

In 2020, many gorillas were born within the Bwindi Impenetrable National Park's gorilla population; an exceptional number of 6 gorillas within 7 weeks…

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Increased Gorilla Density May Lead to Increased Aggression

The number of mountain gorillas on the Virunga Volcanoes has increased continuously for four decades now, as was shown during the last censuses. The…

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Why Are We Still Studying Gorillas? The Value of Long-Term Research of Bwindi Gorillas

A few years ago, when I was well into my now 30-year career studying gorillas, my father asked me, 'Don't we know enough about gorillas by now?'…

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Conservation Efforts and Costs for Monitoring Gorillas at Douguetsi Site, Gabon

Despite the efforts of conservation NGOs and research teams, the expansion of anthropogenic activities such as bushmeat hunting, logging, and…

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A Tragedy in Bwindi

The silverback Rafiki was killed in Bwindi Impenetrable National Park, presumably by poachers. Rafiki was a member of the mountain gorilla group…

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Essential Components of the Mountain Gorilla Success Story

Over the past five years the conservation community has successfully completed what, to date, have been the most intensive and comprehensive…

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1,063 Mountain Gorillas - What Does this Number Mean?

My entire childhood was spent in the south of France, on a hill between an evergreen oak forest and the garrigue. Our family had a lot of cats, who…

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A Long-Term Monitoring Programme for Great Apes in Monte Alén National Park

Equatorial Guinea's forests maintain some of the highest levels of biodiversity in Central Africa (Sunderland 2005). Despite its small size, the…

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Mount Tshiaberimu - the Science behind the Mountain of Spirits

The northern sector of Mount Tshiaberimu is an integral part of the Virunga National Park (VNP), the west is adjacent to Lake Edward in North Kivu…

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Reactions of Wild Great Apes to Camera-trap Devices

Camera trapping has become a predominant method for wildlife monitoring (Burton et al. 2015; Steenweg et al. 2017), including primates (Gerber et al.…

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Population of Bwindi Gorillas Increases to 459 Animals

Taking into account the latest census from Bwindi-Sarambwe, and including the figures for Virunga gorillas from the 2015-2016 census, the global total…

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Gorillas on the IUCN Red List of Threatened Species

A recent change in the mountain gorilla listing on the IUCN Red List of Threatened Species from Critically Endangered (CR) to Endangered (EN) received…

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GRASP & IUCN Great Apes Status Report 2018: Summary

Great ape populations in Africa and Asia are severely threatened by the combined impacts of habitat loss, poaching, illegal trade, and disease. Since…

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First Video Footage of the Elusive Ebo Gorillas in Cameroon

Gorillas were 'discovered' in the Ebo forest in 2002 (Morgan et al. 2003) and since then the Zoological Society of San Diego's Ebo Forest Research…

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Give Me Your Dung And I Will Tell You Who You Are

In many primate species individuals coordinate their activities, share space and form groups. But how do groups form, how long can they exist and how…

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Long-term Biomonitoring on Great Apes Using Camera Traps at Kahuzi-Biega

Kahuzi-Biega National Park (KBNP) is home to exceptionally diverse flora and fauna and represents an important site in the Albertine Rift, one of the…

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New Population Estimate for Western Lowland Gorillas

Kamaya, Loango National Park, Gabon (© Martha Robbins)

In a paper published in the journal Science Advances, Samantha Strindberg, Fiona Maisels and 52 coauthors provide the most comprehensive assessment to…

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Number of Virunga Gorillas Increased again!

In 2015 to 2016 another gorilla census was conducted in the Virunga Volcanoes - and as the censuses before, the result was very positive again. It…

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Tribute to Kanyonyi

It is with great sadness to inform you about the loss of one of my favorite gorillas in Bwindi, Kanyonyi, the lead silverback of Mubare group. He died…

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Survey of the Cross River Gorilla at the Tofala Hill Wildlife Sanctuary in Cameroon

In January 2014 I started to study the ecology of Cross River gorillas at the Tofala Hill Wildlife Sanctuary (THWS) in collaboration with the local…

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On the Road to Extinction? A Population Estimate of Great Apes in Itombwe

Periodic censuses of threatened wildlife populations of high profile species help us to understand their population dynamics, assess the success of…

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First Twins Born to Habituated Western Lowland Gorillas

At the end of January 2016 the Dzanga-Sangha Protected Areas complex in the Central African Republic recorded the first ever western lowland gorilla…

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Gorilla Habituation for Research and Tourism in Loango

Two components of gorilla conservation are research and tourism. Research provides the baseline information concerning the natural ecological and…

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Grauer’s Gorilla Population Reduced Dramatically

Grauer's gorillas are a subspecies of eastern gorillas and live in eastern Democratic Republic of the Congo - an area where fighting between various…

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The Sarambwe Reserve: Current Developments and Threats

This article documents activities implemented in the Sarambwe Reserve and the almost continuous threats to the conservation of the reserve. It is…

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The Status of Grauer's Gorilla in the Usala Forest

Nkomo mountain which supports gorillas, taken from Rama village (© Stuart Nixon)

The Usala forest sits at the heart of the 30,000 km² Maiko Tayna region of eastern Democratic Republic of the Congo, and is among the most intact,…

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Using Remote Video Camera Traps for Multi-Species Assessments in Gabon

Camera trap (© Josephine Head)

Accurate population assessments of endangered species are of great importance for determining conservation priorities and measuring the success of…

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Rukina - Life Summary

[Translate to EN:] Der Silberrückenmann Rukina, der die Kyagurilo-Gruppe in Bwindi geleitet hat, ist gestorben. (© Martha M. Robbins/MPI-EVAN)

We estimate that Rukina was born around 1984. He was well identified as a group member of the Kyagurilo Group in the late 1990s when he was a young…

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Maiko National Park Progress Report

Maiko National Park, Democratic Republic of the Congo, lies in one of the most remote forest areas in the world. It is an incredible wilderness area,…

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Gorilla Group Formation and Dynamics

Gorillas spend the major part of their life in small social groups led by a mature silverback male. Only young blackback males and mature silverback…

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Two Silverbacks Die in Rwanda

The 21-year-old silverback male Umushikirano (Rano), leader of Titus group in Volcanoes National Park, was found dead on July 28, 2014 by trackers.…

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History of Habituated Gorillas in Bwindi

[Translate to EN:] Mutter und Kind in der Kyagurilo-Gruppe

Habituation of wild gorillas has long been a useful tool for research and conservation programs. Decisions to habituate gorillas typically reflect a…

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Getting off the "in Danger" List: Kahuzi-Biega

A poacher camp in the Kahuzi-Biega National Park (© ICCN)

The Kahuzi-Biega National Park (KBNP) has been a UNESCO World Heritage Site since 1980. Since 1997, it has been on the list of World Heritage Sites in…

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Two Leading Silverbacks Die

Mishaya, the leader of the Mishaya group, died on 3 February, 2014 at the age of 28 years after a short illness. Preliminary results indicate that his…

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Gorillas in the Dimonika Biosphere Reserve

Approaching the Dimonika Biosphere Reserve

Designated in 1988 under the UNESCO Man and the Biosphere Program, Dimonika Biosphere Reserve is located in the central Mayombe Mountain chain in the…

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Blood Samples from Tshiaberimu Gorillas

On a small forested island in the western region of the Democratic Republic of the Congo's Virunga National Park, a tiny population of Grauer's…

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DFGF Grauer’s Gorilla Program

[Translate to EN:] Das Biruwe-Team (©DFGFI)

The Dian Fossey Gorilla Fund In­ter­na­tio­nal (DFGFI) has expanded its efforts in the Democratic Republic of the Congo (DRC) to build a new Grauer’s…

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Gorilla Guardian Update

Takpe chief receiving WCS in the community (© WCS/Takamanda-Mone Landscape Project)

The Cross River gorilla (Gorilla gorilla diehli) is Critically Endangered, with perhaps fewer than 250 individuals remaining within their range, which…

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Bwindi Gorilla Number Increased to 400

The census team working (© IGCP)

A census of the gorillas in Bwindi Impenetrable National Park conducted in 2011 confirms a minimum population of 400 gorillas, raising the world…

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