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The Chimpanzees (Pan troglodytes) of the Yoko Council Forest in Cameroon: Abundance, Activity Pattern and Threats

Successful conservation and management of chimpanzees (Pan troglodytes) in Yoko Council Forest (YCF), Centre Cameroon, requires reliable estimates of their population size and density, habitat use and threats. Our study offers the opportunity to improve the knowledge on the population density, distribution and threats of the chimpanzee in this area. We used indirect survey methods using nest counts to estimate the decay rate of the nests. This approach consisted of locating and marking fresh nests (less than 48 hours old) at different periods of time and revisiting them at the end of the inventories to verify whether they had deteriorated or not. Human activities, habitat types, and nesting tree species were also assessed. The mean nest decay rate estimated using a logistic regression analysis was 77.53 days with a nest density of 69.3 [95% CI 54.9-86.7] nests/km2, for an estimated population of about 113 [95% CI 45-280] chimpanzees. In YCF, chimpanzees nest in Marantaceae forests and swampy forests, especially on Khaya grandifolia and Uapaca guineensis trees. Transhumance was the greatest threat in the area (75.33%), followed by hunting (13. 66%), wild sawing (8.81%) and fishing (2.2%). These anthropogenic perturbations were most observed in the south-west sector of the YCF. The area with the greatest density of nests occurred at a site least impacted by human activities. It is essential to regulate these activities in order to guarantee the sustainable management of this precious chimpanzee population.

YCF, Anthropogenic Perturbations, Chimpanzee, Nest Decay Rate, Sustainable Management

APA Style

Serge Alexis Kamgang, Ervis Manfothang Dongmo, Iris Kirsten, Pop Moadomb Jacques Jefferson, André Mveimané, et al. (2023). The Chimpanzees (Pan troglodytes) of the Yoko Council Forest in Cameroon: Abundance, Activity Pattern and Threats. Ecology and Evolutionary Biology, 8(2), 38-49.

ACS Style

Serge Alexis Kamgang; Ervis Manfothang Dongmo; Iris Kirsten; Pop Moadomb Jacques Jefferson; André Mveimané, et al. The Chimpanzees (Pan troglodytes) of the Yoko Council Forest in Cameroon: Abundance, Activity Pattern and Threats. Ecol. Evol. Biol. 2023, 8(2), 38-49. doi: 10.11648/j.eeb.20230802.12

AMA Style

Serge Alexis Kamgang, Ervis Manfothang Dongmo, Iris Kirsten, Pop Moadomb Jacques Jefferson, André Mveimané, et al. The Chimpanzees (Pan troglodytes) of the Yoko Council Forest in Cameroon: Abundance, Activity Pattern and Threats. Ecol Evol Biol. 2023;8(2):38-49. doi: 10.11648/j.eeb.20230802.12

Copyright © 2023 Authors retain the copyright of this article.
This article is an open access article distributed under the Creative Commons Attribution License ( which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

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