Prince T. Mabey^1,, Ambrose Bockarie Kanneh^{2, 3}, Rosa M. Garriga², Inza Koné^{4, 5}, Abu J. Sundufu⁶

Primates’ conservation had faced enormous challenge due to human activities altering ecosystems, combined with inadequate data and existing knowledge gap on their site-specific population size, distribution and trends, threats, climate change impact, human-primate interactions, detailed population recovery plans and strategic monitoring programs. This study examines the species population status (i.e., density, abundance, and geographic distribution) of Pan troglodytes verus (Western chimpanzee), Cercopithecus diana (Diana Monkey) and Colobus polykomos (Black and White Colobus) in a 12.5km2 Forested Island in Pujehun District, Southern, Sierra Leone. The Standing Crop Nest Count (SCNC) method was adopted for the chimpanzee nest count along systematically placed linear line transects for estimation of chimpanzee population. Direct encounter-based technique was carried out along the same transects to account for the population of Diana Monkey and Black and White Colobus. The monkey groups were detected from their vocalization, direct sighting, and the shaking of tree branches during their movement, feeding and other activities. A Compass and Geographical Positioning System (GPS) were used for navigation and a binocular was used to aid in the proper identification of monkey species. Data were entered into Excel tables and encounter rates and other findings were derived. Data from the transect survey were analyzed using QGIS 3.22.0, Excel, and the Distance 7.3 software. A total of 40 chimpanzee nests were detected on 12 transects and the species density of chimpanzee in was 0.25chimpanzee/km2. The species density of Western Black-and-white Colobus within the study area was 57.75/km2 and with an encounter rate of 0.51/km, and 0.89 (signs/km). The encounter rate for the Diana Monkey was 0.37/km2. There were more wildlife direct sightings and signs in areas where less human activities and disturbances were recorded. It is recommended that less human activities be maintained coupled with regular monitoring programs be implemented for adaptive management and conservation of primates in Sierra Leone

primates, human activities, habitat, ecosystem, Jaibui Island