Camera Trapping to Assess Diversity, Habitat Use and Activity Patterns of Mammals in a Tropical Hotspot Area

Abstract

Tropical forest mammal communities, especially those in ecological transition zones, are under constant threat from human activities, but in most cases there is a lack of knowledge about their status, and baseline information on their diversity is lacking in many parts of the world. The Mpem and Djim National Park in central Cameroon is a degraded forest savannah mosaic known to host several globally threatened species. As little is known about the diversity and ecology of the species there, we undertook a rapid assessment using line transects, opportunistic surveys (recce), and camera trapping from September 2021 to December 2021. Our aim was to collect information on species diversity, population status, relative abundance, activity patterns and potential threats to inform conservation priorities for park managers. After 1700 trapping days, we obtained 915 camera events (mean per location = 29.5). The species richness was 32 large, medium-sized and small mammals. The mammal species monitored belonged to 18 families and 10 orders. The family Antilopinae obtained the highest relative abundance index (RAI, 26.24) and relative frequency (RF, 0.49), and the members of this family were the most active (6392 individuals). The Blue Duiker (Philantomba monticola, Thunberg, 1789) had the highest relative abundance index (RAI, 16.47) and relative frequency (RF, 0.31). No significant difference was found between RAI, RF, and the number of events between habitat classes. Human tracks and snares were the most abundant human activity recorded (ER, 0.42 and 0.22 signs per km). The alpha diversity suggests a high diversity within the community with an almost even distribution of species and no dominance of one species over another. We estimated a lower richness but a very low probability of recording new taxa (Q = 0.99). Our results also suggest a spatio-temporal niche partitioning and niche overlap between some duikers, with the highest overlap coefficient obtained between Cephalophus callipygus, Peters, 1876, and Cephalophus dorsalis, Grey, 1846 (Δ = 0.81) and Genetta maculata, Grey, 930 vs. Genetta servalina, Pucheran, 1855 (Δ = 0.82). Our observations provide a baseline for long-term monitoring of terrestrial vertebrates in MDNP.