Determining baselines and trends of Eastern chimpanzees and forest elephants in a Central African protected area after civil strife

Protected areas are crucial to safeguard Sub-Saharan Africa’s extraordinary and abundant megafauna. In many of these areas, instability has derailed conservation efforts and impeded adequate wildlife monitoring. Discovered in 2004, Eastern chimpanzees are found in the Central Uele Basin in northern Democratic Republic of Congo (DRC) within the Bili-Uéré Protected Areas Complex (BUPAC), the largest contiguous protected area in the country. BUPAC is threatened by habitat destruction, mining, wild meat trade, and insecurity. BUPAC chimpanzees are part of the largest remaining continuous population of the species in Africa; they are also being behaviourally unique. Forest elephants were frequent in the 1960’s in the BUPAC but have declined significantly up to 2004 - 2007. We used line transects to estimate Eastern chimpanzee and forest elephant density in the BUPAC core area in 2016 and 2019 and compared these with the 2004-2007 surveys. A total of 37 and 137 two km long line transects were systematically placed in 5,841 km2 and 6,176 km2 survey areas in 2016 and 2019, respectively. We found that chimpanzee density did not change during the two survey periods but indicators for forest elephant density decreased eight-fold. Human activities were detected mainly along the core area periphery in both survey years, where they overlapped with centres of animal activity. The stable high density of chimpanzees is a positive outcome for the core BUPAC. However, despite being a conservation priority area that has received relatively intensified protection, declining forest elephant numbers are likely to reflect the high number of human conflict hotspots in vicinity as well as the increasing human population density around the core area. We propose by elevating the core area to National Park whilst strengthening on the ground enforcement and management structures as well as legal measures against poaching might ensure the long-term survival of such an important area in Africa

A camera trap survey in the community zone of Lobéké National Park (Cameroon) reveals a nearly intact mammalian community

peer reviewedEstimating the richness and abundance of animal species remains central to any conservation strategy of a given area. In remote and challenging environments such as tropical forests, camera traps have proven to be successful in documenting secretive wildlife communities compared to other survey methods, as they allow continuous monitoring without the presence of a human observer. Here, we used camera traps to characterise the community of medium and large terrestrial mammals in the community zone of Lobéké National Park, in southeastern Cameroon. We deployed a grid of 40 camera traps over a 5-week period, recording 5156 independent detection events over 1284 camera days. We recorded 35 species, many of them showing high detection rates compared to other sites in central Africa. These results highlight the little disturbance of the studied area within the park despite its accessibility to local communities. These results obtained from a standardised approach using an expanding technology offer valuable information about the wildlife community of Lobéké, and new insights for reconciling human activities with wildlife conservation.Évaluer la richesse et l’abondance des espèces animales reste un élément clé de toute stratégie de conservation d’une zone donnée. Dans les environnements éloignés et difficiles tels que les forêts tropicales, les caméras-pièges se sont avérées efficaces pour documenter les communautés secrètes d’animaux sauvages par rapport aux autres méthodes d’enquête, car elles permettent un suivi continu sans la présence d’un observateur humain. Dans cette étude, nous avons utilisé des caméras-pièges pour caractériser la communauté des mammifères terrestres de taille moyenne et grande dans la zone communautaire du parc national de Lobeke, dans le sud-est du Cameroun. Sur une période de 5 semaines, nous avons déployé une grille de 40 caméras-pièges, enregistrant 5156 événements de détection indépendants sur 1284 jours de surveillance. 35 espèces ont été enregistrées, la plupart d’entre elles présentant des taux de détection élevés par rapport à d’autres sites d’Afrique centrale. Les résultats obtenus montrent que la zone étudiée est peu perturbée au sein du parc, malgré son accessibilité aux communautés locales. Grâce à ces résultats obtenus à partir d’une approche standardisée utilisant une technologie en expansion, nous disposons d’informations précieuses sur la communauté faunique de Lobéké et de nouvelles perspectives pour concilier les activités humaines et la conservation de la faune

Range-wide indicators of African great ape density distribution

Species distributions are influenced by processes occurring at multiple spatial scales. It is therefore insufficient to model species distribution at a single geographic scale, as this does not provide the necessary understanding of determining factors. Instead, multiple approaches are needed, each differing in spatial extent, grain, and research objective. Here, we present the first attempt to model continent-wide great ape density distribution. We used site-level estimates of African great ape abundance to (1) identify socioeconomic and environmental factors that drive densities at the continental scale, and (2) predict range-wide great ape density. We collated great ape abundance estimates from 156 sites and defined 134 pseudo-absence sites to represent additional absence locations. The latter were based on locations of unsuitable environmental conditions for great apes, and on existing literature. We compiled seven socioeconomic and environmental covariate layers and fitted a generalized linear model to investigate their influence on great ape abundance. We used an Akaike-weighted average of full and subset models to predict the range-wide density distribution of African great apes for the year 2015. Great ape densities were lowest where there were high Human Footprint and Gross Domestic Product values; the highest predicted densities were in Central Africa, and the lowest in West Africa. Only 10.7% of the total predicted population was found in the International Union for Conservation of Nature Category I and II protected areas. For 16 out of 20 countries, our estimated abundances were largely in line with those from previous studies. For four countries, Central African Republic, Democratic Republic of the Congo, Liberia, and South Sudan, the estimated populations were excessively high. We propose further improvements to the model to overcome survey and predictor data limitations, which would enable a temporally dynamic approach for monitoring great apes across their range based on key indicators