In 2016, the eastern lowland gorilla (Gorilla beringei graueri), also known as Grauer's gorilla, was identified as critically endangered because of the precipitous drop in its population by more than 77% over the past few decades. The critically endangered designation, assigned by the International Union for Conservation of Nature (IUCN), indicates that this animal faces the highest possible risk of going extinct in the wild. The previous population analysis of the eastern lowland gorilla was last done in 1994; at that time, these gorillas were estimated to number approximately 17,000. Today, fewer than 3800 individuals remain. The predominant cause of the gorillas' population decline is the years of civil war and resettlement in and around the Democratic Republic of Congo. The consequent elimination of secure oversight of the low-altitude tropical rainforests in the eastern half of the country, to which Grauer's gorillas are confined, allowed the animals to be decimated by a combination of deforestation and forest fragmentation, as well as by hunters for the illegal bushmeat trade. Without concerted, sustained conservation efforts, the eastern lowland gorilla may be extinct within 5 years. See also: Conservation (species); Deforestation: a global concern; Endangered species; Extinction (biology); Population ecology; Population viability; Rainforest
Gorillas (genus Gorilla) are the largest living primates. These great apes are endemic to the forests of central Africa and comprise two species, each subdivided into two subspecies: the western gorilla (G. gorilla), consisting of the western lowland gorilla (G. g. gorilla) and the Cross River gorilla (G. g. diehli); and the Eastern gorilla (G. beringei), consisting of the mountain gorilla (G. b. beringei) and the eastern lowland gorilla (G. b. graueri). The latter subspecies was named after the Austrian zoologist Rudolf Grauer, who identified it in the early 1900s. With the 2016 reevaluation of the conservation status for Grauer's gorilla, all four subspecies of gorillas are now placed in the IUCN's critically endangered category. See also: Apes; Primate conservation efforts
The eastern lowland gorilla is the largest subspecies of gorilla. Males typically weigh more than 205 kg (450 lb) and can stand more than 1.8 m (6 ft) in height; females weigh half as much as males and usually measure around 1.5 m (5 ft) in height. In general, Grauer's gorillas are identified by a stocky body and a short muzzle. Like other gorillas, they have black coats, and the coats turn silver on the backs of the adult male members. They also have large hands, with thumbs that are atypically larger than the other fingers. The diet of these creatures consists of fruits, herbs, leaves, bark, and vines, although insects are consumed occasionally. With the clearing away of the tropical forests for agricultural or mining purposes, the natural habitats of Grauer's gorillas are declining rapidly: these animals now occupy only about 13% of their historical range. The prospects for the survival of the eastern lowland gorillas are thus not encouraging. See also: Environmental management; Forest management