Eastern gorilla
Eastern gorilla[1] Temporal range: Pleistocene to recent
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Male | |
Female with infant Both are mountain gorillas, photographed in Bwindi Impenetrable Forest | |
Scientific classification | |
Domain: | Eukaryota |
Kingdom: | Animalia |
Phylum: | Chordata |
Class: | Mammalia |
Order: | Primates |
Suborder: | Haplorhini |
Infraorder: | Simiiformes |
Family: | Hominidae |
Subfamily: | Homininae |
Genus: | Gorilla |
Species: | G. beringei
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Binomial name | |
Gorilla beringei Matschie, 1903
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Subspecies | |
Eastern gorilla range
Extant (resident)
Possibly extant (resident)
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The eastern gorilla (Gorilla beringei) is a
Taxonomy and phylogeny
There are two recognised subspecies of eastern gorilla: the mountain gorilla (Gorilla beringei beringei) of the volcanic slopes of Rwanda, Uganda and eastern Democratic Republic of Congo; and the eastern lowland gorilla or Grauer's gorilla (Gorilla beringei graueri) in eastern Democratic Republic of Congo.
The eastern lowland gorillas and mountain gorillas were previously thought to be two of the three subspecies of one single species, the gorilla (Gorilla gorilla). However, genetic research has shown that the two eastern subspecies are far more closely related than the western subspecies: the western lowland gorilla (G. gorilla gorilla), which justified the separate classification.[8] The two eastern subspecies are now classified as G. beringei.
Description
The eastern gorilla is a large
Distribution and ecology
Mountain gorillas are restricted to the mountain rainforest and subalpine forest of eastern Democratic Republic of the Congo (DRC), southwestern Uganda and Rwanda. Grauer's gorilla occur across the forests of the Albertine Rift in eastern DRC.
Eastern gorillas are herbivorous, with a heavily foliage based diet, due to lack of available fruit in their habitats. They have smaller home ranges than western gorillas as foliage is more abundant than fruit. They are diurnal but the majority of foraging occurs in the morning and late afternoon. At night, they build nests by folding over vegetation, usually on the ground.
Behavior
Eastern gorillas live in stable, cohesive family groups, led by a dominant silverback male. Eastern gorillas tend to have larger group sizes than their western relatives, numbering up to 35 individuals. There is no distinct breeding season and females give birth only once every 3–4 years due to the long period of parental care and a gestation period of 8.5 months. Newborn gorillas have greyish-pink skin and can crawl after 9 weeks; they are not fully weaned until 3.5 years. Males defend their females and offspring using their large size in intimidating displays involving charging and chest-beating.
Conservation status
The eastern gorilla has become increasingly endangered since the 1990s, and the species was listed as critically endangered in September 2016 as its population continued to decrease. Primary threats to the eastern gorilla include habitat destruction for residential, commercial, and agricultural purposes, habitat fragmentation caused by transportation corridors and resource extraction, as well as disease.[2] Between 1996 and 2016, the eastern gorilla lost more than 70 percent of its population, and by 2016 the total population was estimated to be less than 6,000.[7] An exception to this declining trend is the mountain gorilla. According to the most recent estimates, there are approximately 1,004 mountain gorillas, and their numbers continue to grow.[12]
In some national parks, viewing mountain gorillas is a popular tourist attraction. These national parks include Volcanoes National Park in Rwanda, Virunga National Park in the Democratic Republic of the Congo, and Mgahinga Gorilla National Park and Bwindi Impenetrable National Park in Uganda. While ecotourism can benefit gorilla populations by generating revenue for conservation efforts,[13] there is concern that increased exposure to humans will place gorillas at greater risk of contracting zoonotic diseases.[14] Studies have shown that habituated eastern gorillas, that is, those that leave protected areas to forage in surrounding communities, have higher diseases rates than their unhabituated counterparts, with nearby humans and livestock as the likely sources of transmission.[15]
Unlike the western gorilla, there are few eastern gorillas in zoos. The Antwerp Zoo is the only zoo outside the native range of the species that has eastern gorillas. Outside the native range, the mountain gorilla is not held in captivity at all.[16] Small groups consisting of animals confiscated from poachers are kept in the Democratic Republic of Congo: Grauer's gorillas at the Gorilla Rehabilitation and Conservation Education (GRACE) center in Tayna Nature Reserve ,[17] and mountain gorillas at the Senkwekwe Center in Virunga National Park.[18]
References
- OCLC 62265494.
- ^ . Retrieved 12 November 2021.
- ^ "Appendices | CITES". cites.org. Retrieved 14 January 2022.
- S2CID 235257115.
- ^ "The most recent surveys of Mountain Gorillas estimated that there are now at least 1,004 individuals – IUCN Red List". IUCN Red List of Threatened Species. 31 July 2018. 31 July 2018.
- ^ "The Eastern Gorilla listed on Red List of Endangered Species by IUCN". CBSnews. AP. 4 September 2016. Retrieved 4 September 2016.
- ^ a b "Four out of six great apes one step away from extinction – IUCN Red List". 4 September 2016. Archived from the original on 8 September 2016. Retrieved 4 September 2016.
- ISBN 978-0-521-79281-3.
- ISBN 1-4081-2256-1.
- ISBN 0-7894-7764-5.
- ^ ISBN 978-0-85112-235-9
- . Retrieved 23 October 2022.
- ^ Okello, M. M & Novelli, Marina (1 January 2014). "Tourism in the East African Community (EAC): Challenges, opportunities, and ways forward". Sage. 14: 53–66 – via SAGE journals.
- ISSN 0966-9582.
- PMID 30619805.
- ISBN 0-618-08360-X.
- ^ The Dian Fossey Gorilla Fund. "The GRACE Center for Rescued Gorillas". Archived from the original on 19 July 2013. Retrieved 16 August 2013.
- ^ "Senkwekwe Orphan Mountain Gorilla Center". Archived from the original on 1 December 2017. Retrieved 16 August 2013.