Surviving on the edge: a conservation-oriented habitat analysis and forest edge manipulation for the hazel dormouse in the Netherlands

We studied the effect of a forest edge management quasi-experiment on hazel dormouse (Muscardinus avellanarius) nest numbers in the reproductive season in the Netherlands. We found that the number of nests increased significantly from 2009 to 2013 in managed edges after clearing 75–100 % of mature trees, with a peak in the second year, whereas those in unmanaged edges decreased. In addition, we studied habitat characteristics in forest edges and hedgerows, and found a positive effect of a high upper shrub layer and a high abundance of blackberry (Rubus fruticosus agg. and Rubus spp.), rowan (Sorbus aucuparia) and common hawthorn (Crataegus monogyna) on nest densities. Based on these results, we propose a potential dormouse management strategy that extends conventionally advocated coppice management for regions with well-developed forest edges by (i) postulating a blackberry-oriented landscape restoration approach and (ii) using clearing of mature trees as a tool to boost local dormouse populations in forest edges that have become unsuitable as dormouse habitat due to vegetational succession.