Data for: Nest material preferences in wild hazel dormice Muscardinus avellanarius: Testing predictions from optimal foraging theory

Obtaining nesting material presents an optimal foraging problem, collection of materials incurs a cost in terms of risk of predation and energy spent, and individuals must balance these costs with the benefits of using that material in the nest. The hazel dormouse, Muscardinus avellanarius is an endangered British mammal in which both sexes build nests. However, whether material used in their construction follows the predictions of optimal foraging theory is unknown. Here, we analyse the use of nesting materials in forty two breeding nests from six locations in Southwest England. Nests were characterised in terms of which plants were used, the relative amount of each plant, and how far away the nearest source was. We find that dormice exhibit a preference for plants closer to the nest, but that the distance they are prepared to travel depends on the plant species. Dormice travelled further to collect honeysuckle Lonicera periclymenum, oak Quercus robur, and beech Fagus sylvatica than an..., Characterisation of Dormouse Nests
Hazel dormice nests were obtained from six different sites (Site) throughout Southwest England (Figure 1) in collaboration with Devon Dormouse Group. A total of 42 summer nests (NestID) were used for data collection and analyses. Nests were located on five different species of tree, hazel, (Corylus avellana - 30 nests), oak (Quercus robur - 5 nests), birch (Betula pendula - 3 nests), beech (Fagus sylvatica - 2 nests) and hawthorn (Crataegus laevigata - 2 nests). Nests were separated by hand, and plant materials (Material) were identified using a microscope when necessary (Figure 2 a and b). For the five nests from Pitt’s plantation that were analysed at the nest site, we used a twig to move around the nest material to identify the species. Plant materials were separated by species (both bark and leaf), and we recorded, a) whether a species was used or not (Use), and b) the percentage of each species in the nest (Perc). In all nests hazel bark, honeysuc..., In the file the columns describe the data, but for Effort there is only data for nests where the plant material was used.,