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1. The bii4africa dataset of faunal and floral population intactness estimates across Africa’s major land uses

Author

Hayley S. Clements, Emmanuel Do Linh San, Gareth Hempson, Birthe Linden, Bryan Maritz, Ara Monadjem, Chevonne Reynolds, Frances Siebert, Nicola Stevens, Reinette Biggs, Alta De Vos, Ryan Blanchard, Matthew Child, Karen J. Esler, Maike Hamann, Ty Loft, Belinda Reyers, Odirilwe Selomane, Andrew L. Skowno, Tshegofatso Tshoke, Diarrassouba Abdoulaye, Thierry Aebischer, Jesús Aguirre-Gutiérrez, Graham J. Alexander, Abdullahi H. Ali, David G. Allan, Esther E. Amoako, Samuel Angedakin, Edward Aruna, Nico L. Avenant, Gabriel Badjedjea, Adama Bakayoko, Abraham Bamba-kaya, Michael F. Bates, Paul J. J. Bates, Steven R. Belmain, Emily Bennitt, James Bradley, Chris A. Brewster, Michael B. Brown, Michelle Brown, Josef Bryja, Thomas M. Butynski, Filipe Carvalho, Alan Channing, Colin A. Chapman, Callan Cohen, Marina Cords, Jennifer D. Cramer, Nadine Cronk, Pamela M. K. Cunneyworth, Fredrik Dalerum, Emmanuel Danquah, Harriet T. Davies-Mostert, Andrew D. de Blocq, Yvonne A. De Jong, Terrence C. Demos, Christiane Denys, Chabi A. M. S. Djagoun, Thomas M. Doherty-Bone, Marine Drouilly, Johan T. du Toit, David A. Ehlers Smith, Yvette C. Ehlers Smith, Seth J. Eiseb, Peter J. Fashing, Adam W. Ferguson, José M. Fernández-García, Manfred Finckh, Claude Fischer, Edson Gandiwa, Philippe Gaubert, Jerome Y. Gaugris, Dalton J. Gibbs, Jason S. Gilchrist, Jose M. Gil-Sánchez, Anthony N. Githitho, Peter S. Goodman, Laurent Granjon, J. Paul Grobler, Bonginkosi C. Gumbi, Vaclav Gvozdik, James Harvey, Morgan Hauptfleisch, Firas Hayder, Emmanuel M. Hema, Marna Herbst, Mariano Houngbédji, Brian J. Huntley, Rainer Hutterer, Samuel T. Ivande, Kate Jackson, Gregory F. M. Jongsma, Javier Juste, Blaise Kadjo, Prince K. Kaleme, Edwin Kamugisha, Beth A. Kaplin, Humphrey N. Kato, Christian Kiffner, Duncan M. Kimuyu, Robert M. Kityo, N’goran G. Kouamé, Marcel Kouete T, Aliza le Roux, Alan T. K. Lee, Mervyn C. Lötter, Anne Mette Lykke, Duncan N. MacFadyen, Gacheru P. Macharia, Zimkitha J. K. Madikiza, Themb’alilahlwa A. M. Mahlaba, David Mallon, Mnqobi L. Mamba, Claude Mande, Rob A. Marchant, Robin A. Maritz, Wanda Markotter, Trevor McIntyre, John Measey, Addisu Mekonnen, Paulina Meller, Haemish I. Melville, Kevin Z. Mganga, Michael G. L. Mills, Liaan Minnie, Alain Didier Missoup, Abubakr Mohammad, Nancy N. Moinde, Bakwo Fils E. Moise, Pedro Monterroso, Jennifer F. Moore, Simon Musila, Sedjro Gilles A. Nago, Maganizo W. Namoto, Fatimata Niang, Violaine Nicolas, Jerry B. Nkenku, Evans E. Nkrumah, Gonwouo L. Nono, Mulavwa M. Norbert, Katarzyna Nowak, Benneth C. Obitte, Arnold D. Okoni-Williams, Jonathan Onongo, M. Justin O’Riain, Samuel T. Osinubi, Daniel M. Parker, Francesca Parrini, Mike J. S. Peel, Johannes Penner, Darren W. Pietersen, Andrew J. Plumptre, Damian W. Ponsonby, Stefan Porembski, R. John Power, Frans G. T. Radloff, Ramugondo V. Rambau, Tharmalingam Ramesh, Leigh R. Richards, Mark-Oliver Rödel, Dominic P. Rollinson, Francesco Rovero, Mostafa A. Saleh, Ute Schmiedel, M. Corrie Schoeman, Paul Scholte, Thomas L. Serfass, Julie Teresa Shapiro, Sidney Shema, Stefan J. Siebert, Jasper A. Slingsby, Alexander Sliwa, Hanneline A. Smit-Robinson, Etotepe A. Sogbohossou, Michael J. Somers, Stephen Spawls, Jarryd P. Streicher, Lourens Swanepoel, Iroro Tanshi, Peter J. Taylor, William A. Taylor, Mariska te Beest, Paul T. Telfer, Dave I. Thompson, Elie Tobi, Krystal A. Tolley, Andrew A. Turner, Wayne Twine, Victor Van Cakenberghe, Frederik Van de Perre, Helga van der Merwe, Chris J. G. van Niekerk, Pieter C. V. van Wyk, Jan A. Venter, Luke Verburgt, Geraldine Veron, Susanne Vetter, Maria S. Vorontsova, Thomas C. Wagner, Paul W. Webala, Natalie Weber, Sina M. Weier, Paula A. White, Melissa A. Whitecross, Benjamin J. Wigley, Frank J. Willems, Christiaan W. Winterbach, and Galena M. Woodhouse

Subjects
Science
Abstract

Abstract Sub-Saharan Africa is under-represented in global biodiversity datasets, particularly regarding the impact of land use on species’ population abundances. Drawing on recent advances in expert elicitation to ensure data consistency, 200 experts were convened using a modified-Delphi process to estimate ‘intactness scores’: the remaining proportion of an ‘intact’ reference population of a species group in a particular land use, on a scale from 0 (no remaining individuals) to 1 (same abundance as the reference) and, in rare cases, to 2 (populations that thrive in human-modified landscapes). The resulting bii4africa dataset contains intactness scores representing terrestrial vertebrates (tetrapods: ±5,400 amphibians, reptiles, birds, mammals) and vascular plants (±45,000 forbs, graminoids, trees, shrubs) in sub-Saharan Africa across the region’s major land uses (urban, cropland, rangeland, plantation, protected, etc.) and intensities (e.g., large-scale vs smallholder cropland). This dataset was co-produced as part of the Biodiversity Intactness Index for Africa Project. Additional uses include assessing ecosystem condition; rectifying geographic/taxonomic biases in global biodiversity indicators and maps; and informing the Red List of Ecosystems.

Published
2024
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2. The conservation status and population decline of the African penguin deconstructed in space and time

Author

Deon Geldenhuys, J Visagie, Christina Hagen, Lauren J. Waller, Lorien Pichegru, Henning Winker, B. M. Dyer, Leshia Upfold, Desmond Tom, Andrew D. de Blocq, Richard B. Sherley, Azwianewi B. Makhado, Jessica Kemper, and Robert J. M. Crawford

Subjects
0106 biological sciences, Marine conservation, Spheniscus demersus, Population, Endangered species, extinction risk, 010603 evolutionary biology, 01 natural sciences, 03 medical and health sciences, Cape, lcsh:QH540-549.5, population dynamics, Population growth, IUCN Red List, education, Ecology, Evolution, Behavior and Systematics, 030304 developmental biology, Nature and Landscape Conservation, Original Research, 0303 health sciences, education.field_of_study, Benguela ecosystem, Extinction, Ecology, biology, Bayesian state‐space model, biology.organism_classification, IUCN Red List assessment, seabird conservation, Population decline, Geography, Conservation status, lcsh:Ecology, Demography
Abstract

Understanding changes in abundance is crucial for conservation, but population growth rates often vary over space and time. We use 40 years of count data (1979–2019) and Bayesian state‐space models to assess the African penguin Spheniscus demersus population under IUCN Red List Criterion A. We deconstruct the overall decline in time and space to identify where urgent conservation action is needed. The global African penguin population met the threshold for Endangered with a high probability (97%), having declined by almost 65% since 1989. An historical low of ~17,700 pairs bred in 2019. Annual changes were faster in the South African population (−4.2%, highest posterior density interval, HPDI: −7.8 to −0.6%) than the Namibian one (−0.3%, HPDI: −3.3 to +2.6%), and since 1999 were almost −10% at South African colonies north of Cape Town. Over the 40‐year period, the Eastern Cape colonies went from holding ~25% of the total penguin population to ~40% as numbers decreased more rapidly elsewhere. These changes coincided with an altered abundance and availability of the main prey of African penguins. Our results underline the dynamic nature of population declines in space as well as time and highlight which penguin colonies require urgent conservation attention., Understanding changes in abundance over space and time is crucial for conservation. We use 40 years of count data and Bayesian state‐space models to deconstruct the decline of the African penguin population (almost 65% since 1989) in time and space. Our results underline the dynamic nature of population declines and highlight areas in need of urgent conservation attention, such as the South African colonies north of Cape Town that have declined at nearly 10% per annum since 1999.

Published
2020
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