Practices in sustainable forest management are ruled by national forest policies. Legal standards of forest management applied in Central African region display increasing risks of long-term ...depletion of timber resources. This review aims to assess the effectiveness of sustainable logging practices by highlighting the strengths and weaknesses of the forest management rules applied in Cameroon. The management of the populations of timber tree species is based on population dynamics traits and on measures imposed by national forestry policies. Before any exploitation in natural forest concessions, a management plan must be approved to define the various activities and the potential impacts on the forest. Despite many relevant principles, nearly three decades of forest management in Cameroon have exhibited gaps that need to be addressed in the legal standards of forest management. Proposals for improvement relate to procedures for determining the recovery rate and how considerations on density and seed tree populations should be included into the legal management policies. These suggestions depend on the knowledge of demographic dynamics and the reproductive ecology of the timber taxa as well as a more rapid integration of scientific results into the legal forest management standards.
Overexploitation is one of the main pressures driving wildlife closer to extinction, yet broad‐scale data to evaluate species’ declines are limited. Using African pangolins (Family: Pholidota) as a ...case study, we demonstrate that collating local‐scale data can provide crucial information on regional trends in exploitation of threatened species to inform conservation actions and policy. We estimate that 0.4‐2.7 million pangolins are hunted annually in Central African forests. The number of pangolins hunted has increased by ∼150% and the proportion of pangolins of all vertebrates hunted increased from 0.04% to 1.83% over the past four decades. However, there were no trends in pangolins observed at markets, suggesting use of alternative supply chains. The price of giant (Smutsia gigantea) and arboreal (Phataginus sp.) pangolins in urban markets has increased 5.8 and 2.3 times respectively, mirroring trends in Asian pangolins. Efforts and resources are needed to increase law enforcement and population monitoring, and investigate linkages between subsistence hunting and illegal wildlife trade.
In recent years, both depletion of wild animals and declining food supply have threatened the livelihoods of people inhabiting the forests of the Congo Basin, and rendered the bushmeat trade a ...national and global concern. Because initial approaches to wildlife management were criticized for lacking consideration of the customary rights of local people, a variety of projects have been proposed to ensure their active participation in management initiatives. However, unfamiliar with the concepts of conservation ecology, local people have found it difficult to contribute effectively. This paper proposes an approach to monitor the status of fauna, based on the ratio of blue duikers (Philantomba monticola) to medium-sized duikers (Cephalophusspp.) for the total number of hunting catches (the catch B/M). Analysis of changes in the composition of hunting catches across multiple sites in southeastern Cameroon revealed the following trends: (1) without substantive human intervention, i.e., hunting pressure and forest disturbance, medium-sized duikers were densely distributed while blue duikers were sparse, so that the catch B/M was low; (2) under moderate human intervention, blue duikers became more densely distributed while the original density of medium-sized duikers was maintained, so that the catch B/M increased; (3) with extensive human intervention in specific areas, medium-sized duikers became sparsely distributed while a relatively high density of blue duikers was maintained, so that the catch B/M increased significantly and a mosaic of different compositions of duikers was formed; and (4) with extensive human intervention extending over the specific extensive area, both medium-sized and blue duikers became sparse. It appears that the catch B/M predicts changes in the status of game animals and of the background wild fauna, and is both a sufficiently reliable variable for ecologists and perceptible for local people. Furthermore, this approach has the potential to cultivate a relationship of trust between ecologists and local people, which is indispensable in establishing effective collaborative wildlife management.
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.
Human Footprint and Gross Domestic Product are important indicators for African great ape density.
Highlights
We identified the Human Footprint and Gross Domestic Product as important indicators predicting African great ape density at the continental scale.
Using site‐level abundance data, we predicted density and distribution for African great apes across their entire range.
Overhunting and habitat loss from the expansion of agriculture and extractive industries are the primary threats to primate species, 65% of which are threatened with extinction. In Africa, red ...colobus (
Piliocolobus
spp.) are the most endangered group of monkeys due to their vulnerability to these human pressures. The conservation status of the Critically Endangered Preuss’s red colobus (
P. preussi
), found in southeastern Nigeria and western Cameroon, is not well understood, impeding conservation efforts. We reviewed historical records and recent data on the distribution and abundance of Preuss’s red colobus to assess the species’ population status and provide recommendations for its conservation. Preuss’s red colobus has historically been found in two widely separated populations: one in the contiguous transboundary forests of Nigeria’s Cross River National Park (Oban) and Cameroon’s Korup National Park, and the other in Cameroon’s Ebo–Makombe–Ndokbou forests. Today, Preuss’s red colobus is mostly restricted to Korup and Oban and has largely disappeared from the Ebo–Makombe–Ndokbou forests. Systematic surveys indicate that the population in Korup, where Preuss’s red colobus reaches its highest density, has declined over the last 30 years with possibly 3290–4430 red colobus monkeys remaining. Improving protection of the Korup–Oban population, through improved law enforcement, transboundary conservation, ecological monitoring, and engagement with adjacent local communities, is essential to secure the long-term survival of Preuss’s red colobus. Locating and protecting remnant groups in other forests is also urgently needed. Protecting Preuss’s red colobus will help safeguard some of West Africa’s largest remaining intact forests and other threatened wildlife species.
Parrot populations in Africa and Madagascar are declining and the need for conservation actions to address threats is increasingly recognised. Effective conservation requires a robust knowledge base ...on which decisions over appropriate actions can be made, yet at present there is no current and readily accessible synthesis of the status of populations, the threats they face and knowledge gaps. Here we begin to address this shortfall for the larger species in the region belonging to the genera Coracopsis , Poicephalus , Psittacus and Psittacula . We review developments since the production of the IUCN Parrot Action Plan published in 2000, identify areas where critical knowledge is lacking and highlight opportunities to address them. While advances have been made over the last decade, progress has not been evenly spread, with a strong bias towards populations in southern Africa. To date much research has focused on describing aspects of ecology and behaviour and there remains a need for studies determining the current status of populations and the factors limiting distributions and abundance. This review aims to provide a basis upon which progress towards an improved understanding of the conservation needs of the larger parrots of Africa and Madagascar can be made.
This study identified actual and potential resource-use conflicts around the Mbam and Djerem National Park, Cameroon and elucidated ways of mitigating them. Informal interviews were conducted and ...questionnaires were administered to 263 households from 11 communities. Ninety-one percent of respondents had experienced crop depredation from wildlife over the past two years. A negative relationship was found between distance to park border and the percentage of respondents reporting crop damages by wildlife. Sixty-four percent of respondents reported a positive relationship with conservation authorities, and 38% perceived benefits from the park. More than 95% of respondents in villages closer to the South and West limits of the park reported to perform traditional rituals in the park, although this is currently illegal. Conservation staff reported encroachment into the park by seasonal livestock herders. A participatory zoning plan, strategies for crop compensation, and a conflict management agency should be established at a local level.
In recent years, both depletion of wild animals and declining food supply have threatened the livelihoods of people inhabiting the forests of the Congo Basin, and rendered the bushmeat trade a ...national and global concern. Because initial approaches to wildlife management were criticized for lacking consideration of the customary rights of local people, a variety of projects have been proposed to ensure their active participation in management initiatives. However, unfamiliar with the concepts of conservation ecology, local people have found it difficult to contribute effectively. This paper proposes an approach to monitor the status of fauna, based on the ratio of blue duikers (Philantomba monticola) to medium-sized duikers (Cephalophus spp.) for the total number of hunting catches (the catch B/M). Analysis of changes in the composition of hunting catches across multiple sites in southeastern Cameroon revealed the following trends: (1) without substantive human intervention, i.e., hunting pressure and forest disturbance, medium-sized duikers were densely distributed while blue duikers were sparse, so that the catch B/M was low; (2) under moderate human intervention, blue duikers became more densely distributed while the original density of medium-sized duikers was maintained, so that the catch B/M increased; (3) with extensive human intervention in specific areas, medium-sized duikers became sparsely distributed while a relatively high density of blue duikers was maintained, so that the catch B/M increased significantly and a mosaic of different compositions of duikers was formed; and (4) with extensive human intervention extending over the specific extensive area, both medium-sized and blue duikers became sparse. It appears that the catch B/M predicts changes in the status of game animals and of the background wild fauna, and is both a sufficiently reliable variable for ecologists and perceptible for local people. Furthermore, this approach has the potential to cultivate a relationship of trust between ecologists and local people, which is indispensable in establishing effective collaborative wildlife management.
Though there is consent that poaching is an important driver of wildlife declines in many African forests, we lack a deeper understanding of the factors behind population patterns in Afrotropical ...landscapes to inform conservation management. We surveyed line transects in four Cameroonian sites of different protection status in 2013/2014, namely Korup National Park, Banyang Mbo Wildlife Reserve, one timber concession and a section of an unprotected agroforestry matrix, and used data from 2007 for trend assessment. We used GLMs to identify predictors for mammal distribution based on a set of variables. While species compositions showed complex trend patterns, it is noteworthy that chimpanzee and elephant abundances declined significantly in the Banyang Mbo Wildlife Reserve. Although landscape management type affected the distribution of most mammal species, anthropogenic or environmental variables were strong predictors. Chimpanzee, elephant and drill abundances were higher at a larger distance to settlements. Vegetation density positively affected a number of species, including chimpanzee and red colobus. Several species were more abundant in rough terrain, probably because of reduced poaching. Our results suggest that protected areas in Southwest Cameroon had a mitigating effect on wildlife declines, mainly due to their remoteness and habitat quality, rather than management interventions.
Résumé
Bien qu'il soit admis que le braconnage est un facteur important du déclin de la faune dans de nombreuses forêts africaines, nous n'avons pas une compréhension plus approfondie des facteurs à l'origine des modèles de population dans les paysages afro‐tropicaux, afin d'informer la gestion de la conservation. Nous avons étudié des transects linéaires dans quatre sites camerounais de différents statuts de protection en 2013/2014, notamment le parc national de Korup, la réserve de faune de Banyang Mbo, une concession forestière et une section d'une matrice agroforestière non protégée, et nous avons utilisé les données de 2007 pour évaluer les tendances. Nous avons utilisé des GLM pour identifier les indicateurs de la distribution des mammifères sur la base d'un ensemble de variables. Si la composition des espèces présentait des tendances complexes, il convient de noter que l'abondance des chimpanzés et des éléphants a diminué de manière considérable dans la réserve de faune de Banyang Mbo. Bien que le type de gestion du paysage ait affecté la distribution de la plupart des espèces de mammifères, les variables anthropogéniques ou environnementales étaient des indicateurs importants. Les abondances de chimpanzés, d'éléphants et de forets étaient plus élevées à une plus grande distance des habitations. La densité de la végétation a eu un effet positif sur un certain nombre d'espèces, notamment le chimpanzé et le colobe rouge. Plusieurs espèces étaient plus abondantes sur les terrains accidentés, probablement en raison du braconnage limité. Nos résultats suggèrent que les zones protégées dans le sud‐ouest du Cameroun ont eu un effet atténuant sur le déclin de la faune, principalement en raison de leur éloignement et de la qualité de l'habitat, plutôt que des interventions de gestion.
Estimating duiker populations is essential for conservation programmes in Central Africa, but what the most reliable survey method is remains unclear. We estimated forest duiker population densities ...in Southeast Cameroon using three line‐transect methods: dung counts and diurnal direct observation over 338.2 km, and nocturnal direct observation over 334.7 km. Nocturnal observations resulted in 59.8 and 9.0 individuals km−2 for the blue duiker (Philantomba monticola) and red duikers (Cephalophus callipygus, C. dorsalis, C. leucogaster and C. nigrifrons), respectively, which were much higher than estimates by dung counts and diurnal observation. Only dung counting was applicable for the yellow‐backed duiker (0.8 individuals km−2), due to low encounter rates obtained by the other methods. We argue that nocturnal observation is the most accurate method because the torchlight can pick out duikers' eyes even if the animals are shy and hiding and because multiple counts are unlikely. By contrast, the other methods probably underestimate densities due to poor visibility and reliance on dung production and decay rates calculated in different areas. These results can affect figures used in wildlife management decisions, such as the maximum sustainable yield of game animals, which generally have been based on densities estimated using a single survey method.
Résumé
Il est essentiel d'estimer l'abondance des populations de céphalophes pour les programmes de conservation en Afrique centrale mais on ne sait pas encore vraiment quelle est la méthode d'étude la plus fiable. Nous avons estimé les densités des populations de céphalophes de forêt au sud‐est du Cameroun en utilisant trois méthodes de transects linéaires : comptage des crottes et observations diurnes directes sur 338,2 km, et observations nocturnes directes sur 334,7 km. Les observations nocturnes ont donné des résultats de 59,8 et 9,0 individus km−2 respectivement pour le céphalophe bleu Philantomba monticola et les céphalophes rouges, à savoir C. de Peters Cephalophus callipygus, C. à bande dorsale noire C. dorsalis, C. à ventre blanc C. leucogaster et C. à front noir C. nigrifrons, qui étaient bien plus élevés que les estimations par comptages de crottes et par observations diurnes. Le comptage des crottes n'était applicable que pour le céphalophe à dos jaune C. silvicultor (0,8 individu km−2) en raison du faible indice kilométrique d'abondance obtenu par les autres méthodes. Nous affirmons que l'observation nocturne est la méthode la plus exacte parce que l'utilisation de la lampe torche facilite la détection des céphalophes grâce au reflet de la lumière par leurs yeux même si ces animaux sont timides et se cachent, et parce que des comptages multiples sont peu probables. Par contre, les autres méthodes sous‐estiment probablement la densité en raison d'une visibilité médiocre et d'une mauvaise fiabilité du taux de production et de la vitesse de décomposition des crottes calculés dans différentes zones. Ces résultats peuvent affecter les chiffres utilisés dans la prise de décisions en matière de gestion de la faune, tels que le prélèvement maximum durable, généralement basé sur des densités estimées par une seule méthode de comptage.
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