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bioRxiv · 10.1101/556332

Estimating the abundance of duiker (Cephalophus spp.) populations in African rainforests: an overview of relevant methods

Elenga, G. B. E.·Gaillard, J.-M.·Musibono, D. E. A.·Ifuta, S. N. B.·Bonenfant, C.
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Abstract

Duikers are among the most sought after antelope species for bush meat in central Africa. Estimates of population abundance of duikers based on reliable methods is therefore of prime importance for their sustainable management. Here we retrieved 31 studies from the literature and compared methods used to estimate the abundance of duiker populations in African rainforests. Implemented methods all derived from seven main combinations of sampling designs and population abundance estimators. We then evaluated the relevance of those seven methods by scoring them based on eight criteria selected according to their pros and cons reported in the litterature for large-scale population management of wildlife. For management purposes, methods derived from distance sampling offer the best compromise between the implementation costs and the biological information collected. In particular, both diurnal and nocturnal distance sampling can be recommended. Hunter calls and drive-netting are less reliable, but can be used in association with other measurements in the framework of indicators of ecological changes, a monitoring approach that has been successfully used in temperate ecosystems for managing large herbivores. Funding informationMinistere de lEnvironnement et du Developpement Durable de la Republique Democratique du Congo, Campus France and Centre National de la Recherche Scientifique (CNRS). ResumeLes cephalophes sont parmi les especes dantilopes les plus recherchees pour la viande de brousse en Afrique centrale. Lestimation de labondance des populations de cephalophes revet donc une importance primordiale pour leur gestion durable et adaptative. Nous avons extrait 31 etudes de la litterature et compare les methodes utilisees pour estimer labondance des populations de cephalophes dans les forets tropicales africaines. Les methodes employees derivent de sept combinaisons principales de plans dechantillonnage et destimateurs dabondance. Nous avons evalue la pertinence de ces sept methodes sur la base de criteres selectionnes en fonction de leurs avantages et inconvenients pour une gestion a grande echelle de la population. Les methodes derivees de lechantillonnage par distance offrent le meilleur compromis entre les couts de mise en uvre et les informations biologiques collectees. Les methodes dechantillonnage diurne et nocturne se sont montrees les plus satisfaisantes. Les methodes dappel par les chasseurs et de battue au filet sont moins fiables, mais peuvent etre utilisees en association avec dautres mesures biologiques comme indicateurs de changements ecologiques, une approche qui a ete utilisee avec succes dans les ecosystemes temperes pour la gestion des grands herbivores. Mots-clesgestion durable, grands herbivores, indicateurs de changement ecologique, methode de recensement, viande de brousse

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Elenga, G. B. E., Gaillard, J.-M., Musibono, D. E. A., Ifuta, S. N. B., Bonenfant, C.. 2019-02-21. Estimating the abundance of duiker (Cephalophus spp.) populations in African rainforests: an overview of relevant methods. https://doi.org/10.1101/556332

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