Carnivore diversity in unclassified forests on the right bank of the Aruwimi River in Democratic Republic of Congo (DRC)

Abstract

The forests of the Congo Basin are home to a wide variety of mammals, but this diversity is under pressure from various human activities, notably hunting, agriculture and logging. In the unclassified forests on the right bank of the Aruwimi river, however, scientific knowledge of carnivores remains limited, particularly regarding their species composition, distribution and relative abundance. The aim of this study is therefore to assess the diversity of carnivores in this region by identifying the species present, analysing their distribution according to location and forest habitat type, and estimating their relative abundance based on presence indices. Carnivore diversity is analysed using ecological niche theory. This study adopts a descriptive and comparative ecological approach, based on field surveys. Surveys were carried out at four sites – Libombo, Dikwa, Bopale and Likati – in 2020, 2021, 2022 and 2025 respectively, with a survey effort of 15 days per site. Data collection combined foot patrols (reconnaissance) with surveys along linear transects. In total, 24 5-km recce routes were covered. Direct observations and indirect evidence, including tracks, droppings and food remains, were used to detect and identify species. The data were analysed using the R software package, employing proportions, chi-squared tests and correspondence analysis. The results show that the composition of carnivore communities differs significantly between sites (χ² = 42.587; p = 0.003547) and between forest types (χ² = 17.332; p = 0.01537). Crossarchus alexandri dominates at Bopale, Dikwa and Likati, whilst Libombo exhibits a more balanced composition, notably featuring Civettictis civetta and Lutra maculicollis. A highly significant association is also observed between species and types of presence indices (χ² = 72.131; p < 0.001), demonstrating the value of combining several categories of indices to detect forest carnivores. The detection of Panthera pardus at Dikwa and Profelis aurata at Likati provides further insight into the composition of the carnivore communities studied. In conclusion, the unclassified forests on the right bank of the Aruwimi river are home to a community of carnivores whose composition varies according to location and habitat characteristics. The combination of direct observations and indirect indices constitutes a relevant approach for their inventory and monitoring, whilst maintaining habitat diversity appears important for the conservation of these communities.