Bauld Joshua, Lehmann David, Bussière Luc F, Bush Emma R, Dimoto Edmond, Dikangadissi Jean-Thoussaint, Ukizintambara Tharcisse, White Elizabeth C, Newton Jason, Jones Isabel L, White Lee J T, Musgrave Ruth, Abernethy Katharine A
Biological and Environmental Sciences, University of Stirling, Stirling, UK.
Agence Nationale des Parcs Nationaux (ANPN), Libreville, Gabon.
Am J Primatol. 2025 Mar;87(3):e70012. doi: 10.1002/ajp.70012.
Understanding primate dietary plasticity provides insights into trait evolution and resilience to environmental change. Here, we investigate the feeding ecology of mandrills (Mandrillus sphinx), a species that forms groups of close to 1000 individuals, which presumably impacts feeding ecology by creating exceptionally high feeding competition. Mandrills are also threatened by habitat loss and climate change, and a full understanding of their dietary plasticity is essential to ongoing conservation efforts. Evidence suggests that mandrills are generalist feeders and consume a wide variety of resources to compensate for shortfalls in fruit availability. However, a lack of long-term data on fruit production within the mandrill geographic range means that it is unknown whether the flexible feeding strategies observed previously are stable over multiple years. We combined two rare data sets comprising 8 years of fecal collection and fruit availability to assess the dietary flexibility of mandrills in Lopé National Park, Gabon. We found fruit to be the most frequently consumed resource and fruit consumption covaried positively with fruit availability, peaking during periods of fruit abundance. Mandrill dietary diversity increased during periods of fruit scarcity, through greater consumption of animal prey, leaves, seeds, and other plant fibers. These results demonstrate that mandrills are primarily frugivorous, but that they are also highly flexible feeders, able to respond to temporal variation in fruit production over several annual cycles. In addition, we found that mandrills varied in the extent to which they preferred different fruit taxa. Lipid-rich oil palm (Elaeis guineensis) fruits were by far the most frequently consumed resource and may constitute a staple resource for mandrills in the study site. Our multiyear study provides robust evidence for generalist feeding behavior by mandrills, which may be driven by extreme group sizes or past environmental fluctuations and provide resilience to future environmental change.
了解灵长类动物的饮食可塑性有助于深入了解性状进化以及对环境变化的适应能力。在此，我们研究了山魈（Mandrillus sphinx）的觅食生态，这是一种能形成近1000只个体群体的物种，这种群体规模可能会因产生极高的觅食竞争而影响觅食生态。山魈还受到栖息地丧失和气候变化的威胁，全面了解它们的饮食可塑性对于当前的保护工作至关重要。有证据表明，山魈是杂食性动物，会消耗多种资源以弥补水果供应不足。然而，由于缺乏山魈地理分布范围内水果产量的长期数据，尚不清楚之前观察到的灵活觅食策略在多年间是否稳定。我们结合了两个罕见的数据集，包括8年的粪便收集数据和水果可获得性数据，以评估加蓬洛佩国家公园山魈的饮食灵活性。我们发现水果是最常食用的资源，水果消费量与水果可获得性呈正相关，在水果丰盛期达到峰值。在水果稀缺期，山魈通过更多地食用动物猎物、树叶、种子和其他植物纤维，其饮食多样性增加。这些结果表明，山魈主要以水果为食，但它们也是高度灵活的觅食者，能够在多个年度周期内应对水果产量的时间变化。此外，我们发现山魈对不同水果种类的偏好程度有所不同。富含脂质的油棕（Elaeis guineensis）果实是迄今为止最常食用的资源，可能是研究地点山魈的主要资源。我们的多年研究为山魈的杂食性觅食行为提供了有力证据，这可能是由极端的群体规模或过去的环境波动所驱动，并为未来的环境变化提供适应能力。
