Gorilla species are threatened, albeit to varying degrees. Their survival is threatened above all by the destruction of the habitat caused by the clearing of the forests in which they live. Furthermore, some areas of their range are devastated by civil war and therefore it is difficult to guarantee these animals the necessary protection measures and it is almost impossible to supervise protected areas efficiently.
Another threat factor is hunting for their meat, which is still practiced even though both species are protected. Diseases, in particular Ebola, which continue to affect populations that had already been affected in the past, also contribute to making the situation even worse.
The total population of gorillas is estimated at around 365,000 specimens, distributed very differently among individual populations. The Cross River gorilla, the second subspecies of the western gorilla, inhabits a small area in the border region between Nigeria and Cameroon.
The advance of human settlements has divided its original range into about ten small separate areas and its overall population is estimated at between 250 and 300 specimens. The IUCN classifies this subspecies as critically endangered..
The eastern lowland gorilla is native to eastern Democratic Republic of the Congo; the largest population lives in Kahuzi-Biéga National Park. The civil war that is raging in the region and the extraction of coltan minerals are the main reasons why it is not possible to ensure adequate protection measures against it.
In 2000, the IUCN estimated the total population at between 8,000 and 17,000, but in 2009, the WWF assumed that at most 5,000 remain. In 2015, both environmental organizations estimated the population at 3,800. The western lowland gorilla is by far the most numerous subspecies.
In 2013, its population was estimated at around 360,000 individuals. Today this number is questioned, as it may have declined significantly due to habitat degradation, poaching and Ebola virus outbreaks. This western gorilla subspecies inhabits a large area that is still sparsely populated, where several national parks have also been established.
Furthermore, almost all the gorillas present in zoos belong to it, where, after decades of difficulty, they are now able to reproduce regularly.