Drivers of microhabitat use and vegetation structure selection by the woodland dormouse (Graphiurus murinus) in a riverine forest
摘要
Arboreal small mammals are of particular concern due to their reliance on forest habitats, which are declining, notably in Africa. Most dormice species (Rodentia, Gliridae) are arboreal or semi-arboreal and may serve as indicators of forest habitat quality. However, the ecological requirements of several African dormice species remain poorly understood. We aimed to understand what factors drive the use of microhabitat features and which features are selected by woodland dormice Graphiurus murinus in a riverine Combretum forest in South Africa. We hypothesized that season, individual traits, residency status, connectivity, and vegetation structure and cover influence microhabitat choice. We collected capture–mark–recapture data across four seasons and assessed microhabitat features using a grid of 192 traps set at various heights. Generalized linear and generalized mixed models and comparative tests were used to assess microhabitat use and selection. Dormice were less captured during winter and where only same-sex individuals were present. Microhabitats with a higher number of dormice neighbours and those with animals with longer residency time were more frequently used. Dormice used more well-connected areas, trunks and canopies; favouring higher, denser and more connected vegetation cover. The species predominantly utilized Combretum caffrum, Rhus spp., and Gymnosporia heterophylla, preferring the latter two tree species. The significance of riverine Combretum forest structure for dormice microhabitat use and selection was evident. We suggest management practices potentially relevant to maintain dormice populations (e.g., preventing vegetation gaps larger than 50% per 100 m2) by balancing potential alterations on forest density and structure (e.g., climate change).