Changes in Grauer's gorilla (Gorilla beringei graueri) and other primate populations in the Kahuzi‐Biega National Park and Oku Community Reserve, the heart of Grauer's gorilla global range

A comprehensive survey of Kahuzi-Biega National Park (KBNP) and the contiguous Oku Community Reserve (OCR) reveals that the global population of Grauer's gorillas is significantly higher than previously estimated, at 6,800 individuals, up from an earlier estimate of 3,800. This revision comes from extensive nest counts across 230 line transects, which also indicated a significant decline in gorilla numbers within KBNP itself, while chimpanzee populations remained stable compared to mid-1990s estimates. The study highlights the negative impact of proximity to mines, villages, and roads on ape densities, with higher concentrations found in more rugged and remote areas. Additionally, other primate species, particularly the Endangered Ulindi River Red Colobus, have declined due to bushmeat hunting. These findings suggest that while population declines are less severe than initially feared, conservation efforts must address human encroachment and insecurity to protect these critical habitats.

Plumptre, A. J., Kirkby, A., Spira, C., Kivono, J., Mitamba, G., Ngoy, E., Nishuli, R., Strindberg, S., Maisels, F., Buckland, S., Ormsby, L., & Kujirakwinja, D. (2021). Changes in Grauer’s gorilla (Gorilla beringei graueri) and other primate populations in the Kahuzi‐Biega National Park and Oku Community Reserve, the heart of Grauer’s gorilla global range. American Journal of Primatology, 83(7). Portico. https://doi.org/10.1002/ajp.23288