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Modeling the potential distribution of the threatened Grey-necked Picathartes Picathartes oreas across its entire range

Published online by Cambridge University Press:  15 June 2023

Guilain Tsetagho*
Research Unit of Biology and Applied Ecology, Faculty of Sciences, University of Dschang, Dschang, Cameroon Ebo Forest Research Project, Douala, Cameroon
Tom Bradfer-Lawrence
Biological and Environmental Sciences, Faculty of Natural Sciences, University of Stirling, FK9 4LA, UK Centre for Conservation Science, Royal Society for the Protection of Birds (RSPB), 2 Lochside Drive, Edinburgh, UK
Awa II Taku
Research Unit of Biology and Applied Ecology, Faculty of Sciences, University of Dschang, Dschang, Cameroon
Katharine A. Abernethy
Biological and Environmental Sciences, Faculty of Natural Sciences, University of Stirling, FK9 4LA, UK
Ekwoge E. Abwe
Ebo Forest Research Project, Douala, Cameroon San Diego Zoo Wildlife Alliance, 15600 San Pasqual Valley Road, Escondido, CA 92027
E. Tsi Angwafo
Laboratory of Sylviculture, Wildlife, Protected Areas and Wood Technology, Faculty of Agronomy and Agricultural Sciences (FASA) PO Box 222, University of Dschang, Dschang, Cameroon
Fidelis Atuo
Department of Biology, Southeast Missouri State University, Cape Girardeau, Missouri 63701, USA
Martin Fichtler
Dachverband Deutscher Avifaunisten
Roger Fotso
Wildlife Conservation Society, Yaoundé, Cameroon
Matthew H. Shirley
Global Forensics and Justice Center, Florida International University, 3000 NE 151st St, North Miami Beach, FL 33181, USA Project Mecistops, 5450 Eagles Point Circle #150, Sarasota, FL 34231, USA
Bethan J. Morgan
Biological and Environmental Sciences, Faculty of Natural Sciences, University of Stirling, FK9 4LA, UK Ebo Forest Research Project, Douala, Cameroon San Diego Zoo Wildlife Alliance, 15600 San Pasqual Valley Road, Escondido, CA 92027
Marc Languy
Rue de la Bruyère, B-7743 Obigies, Belgium
Fiona Maisels
Biological and Environmental Sciences, Faculty of Natural Sciences, University of Stirling, FK9 4LA, UK Wildlife Conservation Society, Global Conservation Program, 2300 Southern Boulevard, Bronx, New York, NY 10460, USA
Richard Oslisly
Agence Nationale des Parcs Nationaux, BP 20379 Libreville, Gabon
Luke Powell
Institute of Biodiversity, Animal Health and Comparative Medicine, University of Glasgow, Glasgow, G12 8QQ, Scotland
Thomas Smith
Department of Ecology and Evolutionary Biology, University of California, Los Angeles 621 Charles E. Young Drive South Room LS5120, Box 951606 Los Angeles, CA 90095-1606 USA
Henri A. Thomassen
Institute for Evolution and Ecology, University of Tübingen, Building E, Floor 4, Auf der Morgenstelle 28, Tübingen 72076, Germany
Matthias Waltert
Workgroup on Endangered Species, J. F. Blumenbach Institute of Zoology and Anthropology, Georg-August-Universität Göttingen, Bürgerstr. 50 37073, Göttingen, Germany
Jared Wolfe
College of Forest Resources and Environmental Science, Michigan Technological University, 1400 Townsend Dr. Houghton, MI 49931
Robin C. Whytock
Biological and Environmental Sciences, Faculty of Natural Sciences, University of Stirling, FK9 4LA, UK Okala, 3 More London Riverside, London SE1 2AQ, UK
Corresponding author: Guilain Tsetagho; Email:


Understanding the distribution and extent of suitable habitats is critical for the conservation of endangered and endemic taxa. Such knowledge is limited for many Central African species, including the rare and globally threatened Grey-necked Picathartes Picathartes oreas, one of only two species in the family Picathartidae endemic to the forests of Central Africa. Despite growing concerns about land-use change resulting in fragmentation and loss of forest cover in the region, neither the extent of suitable habitat nor the potential species’ distribution is well known. We combine 339 (new and historical) occurrence records of Grey-necked Picathartes with environmental variables to model the potential global distribution. We used a Maximum Entropy modelling approach that accounted for sampling bias. Our model suggests that Grey-necked Picathartes distribution is strongly associated with steeper slopes and high levels of forest cover, while bioclimatic, vegetation health, and habitat condition variables were all excluded from the final model. We predicted 17,327 km2 of suitable habitat for the species, of which only 2,490 km2 (14.4%) are within protected areas where conservation designations are strictly enforced. These findings show a smaller global distribution of predicted suitable habitat forthe Grey-necked Picathartes than previously thought. This work provides evidence to inform a revision of the International Union for Conservation of Nature (IUCN) Red List status, and may warrant upgrading the status of the species from “Near Threatened” to “Vulnerable”.

Research Article
© The Author(s), 2023. Published by Cambridge University Press on behalf of BirdLife International

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