Wildlife Ecology and Health Group (WE&H), and Servei d'Ecopatologia de Fauna Salvatge (SEFaS), Departament de Medicina i Cirurgia Animals, Facultat de Veterinària, Universitat Autònoma de Barcelona, Bellaterra, Barcelona, Spain.
Ruminant Research Group, Departament de Ciència Animal i dels Aliments, Facultat de Veterinària, Universitat Autònoma de Barcelona, Bellaterra, Barcelona, Spain.
PLoS One. 2019 Jan 23;14(1):e0210819. doi: 10.1371/journal.pone.0210819. eCollection 2019.
In alpine habitats, the seasonally marked climatic conditions generate seasonal and spatial differences in forage availability for herbivores. Vegetation availability and quality during the growing season are known to drive life history traits of mountain ungulates. However, little effort has been made to understand the association between plant phenology and changes in the foraging strategies of these mountain dwellers. Furthermore, this link can be affected by the seasonal presence of livestock in the same meadows. The objective of this work was to study the seasonal changes in diet composition of Pyrenean chamois (Rupicapra p. pyrenaica) and its relationship to primary production trends in a Mediterranean alpine environment. Moreover, diet composition in two populations with contrasting livestock pressure was compared in order to study the effect of sheep flocks on the feeding behaviour of chamois. From 2009 to 2012, monthly diet composition was estimated by cuticle microhistological analysis of chamois faeces collected in the eastern Pyrenees. The primary production cycle was assessed by remote sensing, using the Normalized Difference Vegetation Index. Additionally, the diet of sheep sharing seasonally the subalpine and alpine meadows with chamois was analysed. Diet selection of chamois and sheep and their overlap was also assessed. Our results show an intra-annual variation in the diet composition of Pyrenean chamois and demonstrate a strong relationship between plant consumption dynamics and phenology in alpine areas. In addition, Calluna vulgaris, Cytisus spp. and Festuca spp., as well as forbs in the summer, are found to be key forage species for Pyrenean chamois. Furthermore, this study couldn't detect differences between both chamois populations despite the presence of sheep flocks in only one area. However, the detection of a shift in the diet of chamois in both areas after the arrival of high densities of multi-specific livestock suggest a general livestock effect. In conclusion, Pyrenean chamois are well adapted to the variations in the seasonal availability of plants in alpine habitats but could be disturbed by the seasonal presence of livestock. Due to the key plants in their diet, we suggest that population management programmes should focus on the preservation of mixed grasslands composed of patches of shrubs and herbs. The effects of climate change and shrub expansion should be studied as they may potentially affect chamois population dynamics through changes in habitat composition and temporal shifts in forage availability.
在高山栖息地，季节性明显的气候条件导致食草动物的饲料可获得性在季节和空间上存在差异。在生长季节，植被的可利用性和质量被认为会影响高山有蹄类动物的生活史特征。然而，人们很少努力了解植物物候学与这些山地居民觅食策略变化之间的联系。此外，这种联系可能会受到同一牧场上季节性存在牲畜的影响。本研究的目的是研究比利牛斯山羊（Rupicapra p. pyrenaica）在一个地中海高山环境中的饮食组成的季节性变化及其与初级生产趋势的关系。此外，还比较了两个具有不同牲畜压力的种群的饮食组成，以研究羊群对山羊觅食行为的影响。从 2009 年到 2012 年，通过对在比利牛斯山脉东部收集的山羊粪便进行表皮微组织学分析，估计了每月的饮食组成。利用归一化植被指数（NDVI）通过遥感评估初级生产周期。此外，还分析了与山羊共享亚高山和高山牧场的绵羊的饮食。还评估了山羊和绵羊的饮食选择及其重叠。我们的研究结果表明，比利牛斯山羊的饮食组成存在年内变化，并证明了高山地区植物消耗动态与物候之间的强相关性。此外，发现石南、雀麦属和羊茅属以及夏季的野花是比利牛斯山羊的关键饲料物种。此外，尽管在一个地区只有绵羊群存在，但本研究未能检测到两个山羊种群之间的差异。然而，在多物种牲畜高密度到达后，两个地区的山羊饮食都发生了变化，这表明存在一般的牲畜影响。总之，比利牛斯山羊很好地适应了高山栖息地中植物季节性可获得性的变化，但可能会受到季节性存在牲畜的干扰。由于它们的饮食中的关键植物，我们建议种群管理计划应侧重于保护由灌木和草本植物斑块组成的混合草地。应研究气候变化和灌木扩张的影响，因为它们可能会通过栖息地组成的变化和饲料可获得性的时间推移，对山羊种群动态产生影响。
