Impacts écologiques du retour du castor européen sur la distribution spatiale et la densité de "Boloria eunomia"

Details

Supervisors

Schtickzelle, Nicolas ; Brans, Victor

Faculty

Faculté des sciences

Degree label

Master [120] en biologie des organismes et écologie, à finalité approfondie

Abstract

enCurrently, the Earth is facing many global changes that are destabilizing all the processes put in place at the end of millions of years of evolution. As lepidopteran populations can be among the victims, it is essential to study their metapopulations. Here, populations of the bog fritillary (Boloria eunomia) have been restudied in 5 different sites on the plateau des Tailles, in the Belgian Ardenne. The study focused on the impact that the European beaver (Castor fiber) could have on this species of butterfly. Indeed, this engineering species, reintroduced in Belgium a few years ago, can also be a source of disturbance for B. eunomia. Thus, it was undertaken here to calculate the probability of the beaver settling in the metapopulation network of this butterfly and to infer the consequences that this would have on this lepidoptera. The results revealed some trends. Indeed, areas suitable for Boloria eunomia would have little probability of European beaver settlement, whereas areas suitable for the latter would not be suitable for this butterfly. In addition, areas with a significant spruce cover would be unfavourable to both species. It has also been shown that beavers can have a negative impact on certain populations of the bog fritillary, particularly those located on the banks of rivers. The data collected here are thus intended to be the beginning of a large-scale comparative study of the impact of this rodent on this species of butterfly. Indeed, since this thesis could not confirm with certainty the impact trends of this animal, many other studies would be necessary to support it.