Bonobo; IUCN SSC A.P.E.S. database; chimpanzee; gorilla; range-wide assessment; Africa, Central; Africa, Western; Animals; Central African Republic; Data Collection; Gorilla gorilla; Pan troglodytes; Hominidae; Ecology, Evolution, Behavior and Systematics; Animal Science and Zoology
Abstract :
[en] 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.
Disciplines :
Zoology
Author, co-author :
Ordaz-Németh, Isabel ; Department of Primatology, Max Planck Institute for Evolutionary Anthropology, Leipzig, Germany
Sop, Tenekwetche; Department of Primatology, Max Planck Institute for Evolutionary Anthropology, Leipzig, Germany
Amarasekaran, Bala; Tacugama Chimpanzee Sanctuary, Freetown, Sierra Leone
Bachmann, Mona ; Department of Primatology, Max Planck Institute for Evolutionary Anthropology, Leipzig, Germany
Boesch, Christophe ; Department of Primatology, Max Planck Institute for Evolutionary Anthropology, Leipzig, Germany ; Wild Chimpanzee Foundation, Leipzig, Germany
Brncic, Terry; Wildlife Conservation Society, Global Conservation Program, New York, New York, USA
Caillaud, Damien ; Dian Fossey Gorilla Fund International, Atlanta, USA ; Department of Anthropology, University of California, Davis, California, USA
Campbell, Geneviève ; The Biodiversity Consultancy Ltd., Cambridge, UK
Carvalho, Joana ; Faculty of Natural Sciences, University of Stirling, Stirling, Scotland, UK
Chancellor, Rebecca ; Departments of Anthropology & Sociology and Psychology, West Chester University, West Chester, Pennsylvania, USA
Davenport, Tim R B; Wildlife Conservation Society, Global Conservation Program, New York, New York, USA
Greengrass, Elizabeth; Born Free Foundation, Broadlands Business Campus, Horsham, West Sussex, UK
Heinicke, Stefanie ; Department of Primatology, Max Planck Institute for Evolutionary Anthropology, Leipzig, Germany ; Biodiversity Conservation group, German Centre for Integrative Biodiversity Research (iDiv) Halle-Leipzig-Jena, Leipzig, Germany ; Transformation Pathways Research Department, Potsdam Institute for Climate Impact Research, Potsdam, Germany
Herbinger, Ilka; WWF Germany, Berlin, Germany
Inkamba-Nkulu, Clement; Wildlife Conservation Society, Global Conservation Program, New York, New York, USA
Iyenguet, Fortuné; Wildlife Conservation Society, Global Conservation Program, New York, New York, USA
Junker, Jessica ; Biodiversity Conservation group, German Centre for Integrative Biodiversity Research (iDiv) Halle-Leipzig-Jena, Leipzig, Germany
Bobo, Kadiri S; Department of Forestry, Faculty of Agronomy and Agricultural Sciences, The University of Dschang, Dschang, Cameroon
Lushimba, Alain; IUCN, Regional Program Central and West Africa, Ouagadougou, Burkina Faso
Maisels, Fiona ; Wildlife Conservation Society, Global Conservation Program, New York, New York, USA ; Faculty of Natural Sciences, University of Stirling, Stirling, Scotland, UK
Malanda, Guy Aimé Florent; Parc National d'Odzala-Kokoua, Brazzaville, Republic of Congo
McCarthy, Maureen S ; Department of Primatology, Max Planck Institute for Evolutionary Anthropology, Leipzig, Germany
Motsaba, Prosper; Wildlife Conservation Society, Global Conservation Program, New York, New York, USA
Moustgaard, Jennifer; Bonobo Conservation Initiative, Washington, District of Columbia, USA
Murai, Mizuki; Department of Primatology, Max Planck Institute for Evolutionary Anthropology, Leipzig, Germany
Ndokoue, Bezangoye; Wildlife Conservation Society, Global Conservation Program, New York, New York, USA
Nixon, Stuart; Chester Zoo, Cedar House, Chester, UK
Nseme, Rostand Aba'a; Agence Nationale des Parcs Nationaux, Libreville, Gabon
Nzooh, Zacharie; WWF Cameroon, Yaoundé, Cameroon
Pintea, Lilian; Conservation Science, Jane Goodall Institute, Vienna, USA
Plumptre, Andrew J ; KBA Secretariat, c/o BirdLife International, Cambridge, UK
Roy, Justin; Department of Primatology, Max Planck Institute for Evolutionary Anthropology, Leipzig, Germany
Rundus, Aaron; Department of Psychology, West Chester University, West Chester, Pennsylvania, USA
Sanderson, Jim; Small Wild Cat Conservation Foundation, Corrales, New Mexico, USA
Serckx, Adeline ; Université de Liège - ULiège > Département de Biologie, Ecologie et Evolution > Biologie du comportement - Ethologie et psychologie animale ; Department of Primatology, Max Planck Institute for Evolutionary Anthropology, Leipzig, Germany ; The Biodiversity Consultancy Ltd., Cambridge, UK
Strindberg, Samantha; Wildlife Conservation Society, Global Conservation Program, New York, New York, USA
Tweh, Clement; Wild Chimpanzee Foundation, Leipzig, Germany ; School of Biological Sciences, University of Nairobi, Nairobi, Kenya
Vanleeuwe, Hilde; Wildlife Conservation Society, Global Conservation Program, New York, New York, USA
Waltert, Matthias ; Workgroup on Endangered Species, University of Göttingen, Göttingen, Germany
Williamson, Elizabeth A ; Faculty of Natural Sciences, University of Stirling, Stirling, Scotland, UK
Wilson, Michael ; Departments of Anthropology and Ecology, Evolution and Behavior, University of Minnesota, Minneapolis, Minnesota, USA
Mundry, Roger; Department of Primatology, Max Planck Institute for Evolutionary Anthropology, Leipzig, Germany ; German Primate Center, Leibniz Institute for Primate Research, Göttingen, Germany
Kühl, Hjalmar S ; Department of Primatology, Max Planck Institute for Evolutionary Anthropology, Leipzig, Germany ; Biodiversity Conservation group, German Centre for Integrative Biodiversity Research (iDiv) Halle-Leipzig-Jena, Leipzig, Germany
Robert Bosch Stiftung MPG - Max-Planck-Gesellschaft zur Förderung der Wissenschaften
Funding text :
The authors would like to thank all African great ape range governments and national authorities for permitting the collection of data on great apes. The authors thank the staff of the Bonobo Conservation Initiative, Conservation International's Rapid Assessment Program, Fauna & Flora International, Wild Chimpanzee Foundation, Wildlife Conservation Society, World Wide Fund for Nature, and the Zoological Society of Milwaukee/Bonobo and Congo Biodiversity Initiative for collecting survey data. The authors thank Nsengiyunva Barakabuye, Sylvain Gatti, and Frank P.G. Princée for sharing data. The authors are grateful to Christopher Barrat, Tsegaye Gatiso, Enrique Ordaz, Gaёlle Bocksberger, Frank Zeitschel, Benjamin Debetencourt, and Maria Voigt for advice and helpful discussions. The authors would also like to thank the Robert Bosch Foundation and Max Planck Society for funding and support.The authors would like to thank all African great ape range governments and national authorities for permitting the collection of data on great apes. The authors thank the staff of the Bonobo Conservation Initiative, Conservation International's Rapid Assessment Program, Fauna & Flora International, Wild Chimpanzee Foundation, Wildlife Conservation Society, World Wide Fund for Nature, and the Zoological Society of Milwaukee/Bonobo and Congo Biodiversity Initiative for collecting survey data. The authors thank Nsengiyunva Barakabuye, Sylvain Gatti, and Frank P.G. Princée for sharing data. The authors are grateful to Christopher Barrat, Tsegaye Gatiso, Enrique Ordaz, Gaёlle Bocksberger, Frank Zeitschel, Benjamin Debetencourt, and Maria Voigt for advice and helpful discussions. The authors would also like to thank the Robert Bosch Foundation and Max Planck Society for funding and support. Open access funding enabled and organized by Projekt DEAL.
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