Effects of Human Disturbance on the Endangered Preuss’s Monkey (Allochrocebus preussi) in the Ebo Forest, Cameroon: Implications for Conservation

Background and Aim: Knowledge of population size is crucial for efficient conservation planning. Limited population survey data exist for the Endangered Preuss’s monkey in Cameroon’s Ebo forest, a stronghold for this species and several other IUCN RedList species. In this study, we assessed the population size of Preuss’s monkey in the Ebo forest. Methods: Ecological data on Preuss’s monkey and evidence of anthropogenic disturbances were collected based on recce surveys. Encounter Rate was used to assess abundance and distribution, and for comparing relative abundance among four survey sites. We employed ANOVA to test for significant differences in encounters with Preuss’s monkey across sites in the Ebo forest. We used regression analysis to identify possible relationships between encounters with Preuss’s monkey and anthropogenic activities recorded. Results: Based on direct sightings, we observed 66 individuals residing in 11 groups. This resulted in an encounter rate of 0.15_individuals/km, a sighting frequency of 0.024_groups/km, and an encounter frequency of 0.062_groups/km of Preuss’s monkeys. On average, an encounter rate of 2.4_signs of anthropogenic activities/km was documented. Our results revealed a negative and significant correlation between encounters of Preuss’s monkey and human activities such as hunting signs, logging signs, evidence of planted crops, collection of Non-Timber Forest Products, and fishing activity. Conclusion: Our investigation indicates that the population of Preuss’s monkey in the Ebo forest totals approximately 481 individuals, which is consistent with their Endangered status. Implications for Conservation: We recommend continued monitoring and research on this population to better determine the specific drivers of their population decline. We also advocate a community conservation approach to incentivize local communities to take a more active role in preserving the forest and protecting Preuss’s monkey. Equally important, are programs of conservation education and awareness, in an attempt to inspire local people to become involved in this species conservation.