Hazel dormouse (Muscardinus avellanarius) nest material preferences and collection distances, in southern England

Abstract

Non-hibernating hazel dormice (Muscardinus avellanarius) construct nests in shrub and tree vegetation up to 10 m above the ground. They also readily use and build nests in boxes, which are often used as a tool to monitor populations. The availability of natural nest materials may affect nest site selection or nest box utilisation and to gain a better understanding of this we analysed the materials used in 56 dormouse nests, collected from boxes within six southern English woodlands in 2009, and estimated collection distances. The contribution individual nest materials made to the nests were assessed using dry weights. Out of 56 nests, 15 (26.8%) did not include any material from the plant species to which the nest box was attached. The total number of materials used was 18, with between one and eight materials used per nest (n=56, ̅= 3.54, SD=1.48). The estimated distances travelled to collect these materials ranged from 0 m to 50 m (n=197, ̅=3.29 m, SD=6.06). Dry weights of individual nests ranged from 4.25g to 38.01g (n=56, ̅=18.06 g, SD=8.25 g). The dry weight of an individual material in a nest ranged from 0.25 g (11 different materials) to 30.5 g (honeysuckle bark) (n=197 ̅=4.38 g, SD=5.13 g). Based on dry weight, the percentage contribution of a single material to an individual nest ranged from 0.8% (silver birch leaves) to 96.2% (honeysuckle bark) (n=197, ̅=24.91%, SD=26.37). There were statistically significant negative correlations between the distance travelled and the dry weight of a material (n=197, rs = -0.211, p=0.003), and the distance travelled and the percentage nest weight of a material (n=197, rs = -0.259, p=<0.001), although neither of these associations were particularly informative biologically. Where honeysuckle bark (Lonicera periclymenum) was not closely available, dormice could travel more than twice as far to collect it as any other material. The three furthest distances recorded were 30 m, 45 m and 50 m. Honeysuckle bark was also the most frequently used nest material, occurring in 84% of the sampled nests, and was most often the material comprising the largest dry weight (35.7%). The dry weight and the % of total nest weight of honeysuckle bark were significantly greater than other materials.