Scholte Paul, Pays Olivier, Chardonnet Bertrand, Ouattara Amara, Tiomoko Djafarou
Deutsche Gesellschaft für Internationale Zusammenarbeit (GIZ), Addis Ababa, Ethiopia.
previously Deutsche Gesellschaft für Internationale Zusammenarbeit (GIZ), Abidjan, Côte d'Ivoire.
PLoS One. 2025 May 28;20(5):e0320455. doi: 10.1371/journal.pone.0320455. eCollection 2025.
Africa's wildlife decline has received increasing attention, yet underlying reasons have remained opaque. Using generalized additive models of 25 terrestrial and aerial counts, we present West Africa's first large herbivore population trend series alongside potential drivers. Following Comoé national park's creation in 1968, large herbivore populations increased till the mid-1980s, but subsequently declined, amplified during Côte d'Ivoire's political crisis (2002-2011) when active management ceased. Between 2010-2022, populations of roan, hartebeest and waterbuck have quasi-recovered to pre-crisis numbers. The previously dominant kob, common hippopotamus and savanna elephant have remained at c. 10% of their 1970-80s numbers, however. Grasslands declined from 15 to 2% between 1979-2020, negatively impacting kob and common hippopotamus. Since 1962, surrounding human populations and cattle inside the park increased over six-fold, yet the number of rangers only doubled. These developments have resulted in a different wildlife assemblage. Species typical of long-coarse shrub savanna - hartebeest and roan - have reached pre-crisis levels, contrary to kob and common hippopotamus likely because of the reduction of floodplain grasslands and their gregarious distribution rendering them vulnerable to poaching. We recommend increased efforts to understand habitat changes and poaching pressures, prior to re-introducing extinct species. This study highlights the importance but also the challenges of studying large herbivore populations trends alongside drivers of change.
非洲野生动物数量的减少日益受到关注，但其背后的原因仍不明朗。通过对25次地面和空中计数数据运用广义相加模型，我们呈现了西非首个大型食草动物种群趋势系列以及潜在驱动因素。自1968年科莫埃国家公园创建以来，大型食草动物种群数量在20世纪80年代中期之前有所增加，但随后下降，在科特迪瓦政治危机（2002 - 2011年）期间因积极管理停止而加剧。在2010 - 2022年期间，马羚、转角牛羚和水羚的种群数量已基本恢复到危机前水平。然而，此前占主导地位的水羚、普通河马和草原象的数量仅维持在20世纪70 - 80年代数量的约10%。1979 - 2020年间，草原面积从15%减少到2%，对水羚和普通河马产生了负面影响。自1962年以来，公园周边的人口和园内的牛数量增长了六倍多，但护林员数量仅增加了一倍。这些变化导致了不同的野生动物群落。长粗灌木稀树草原特有的物种——转角牛羚和马羚——已恢复到危机前水平，与之相反，水羚和普通河马数量减少可能是因为洪泛平原草原面积减少以及它们群居的分布方式使其易受偷猎影响。我们建议在重新引入已灭绝物种之前，加大力度了解栖息地变化和偷猎压力。这项研究凸显了研究大型食草动物种群趋势及其变化驱动因素的重要性和挑战。
