Polyandry by wood mice in natural populations

The microhabitat used by the garden dormouse Eliomys quercinus during its nocturnal activity was examined. Twenty-three variables describing habitat structure were measured at 100 trapping points. Logistic regression models were utilized to select the variables that discriminate between used and avoided trapping points and, in a series of pairwise contrasts, between trap sites used by different sexes, age classes and animals in different reproductive periods. Used sites were characterized by a higher (>40%) rock cover, a thicker shrub layer and a younger understory with trees of smaller trunk diameter. These variables describe areas with rockfalls from the upper slope, where trees were younger and smaller, the canopy closure reduced and the shrub layer more developed than in other parts of the forest. Dense shrubby vegetation provided protection from aerial predators and, in conjunction with rocks and stones, might have made hunting by birds and mammals more difficult. Garden dormice may also have been attracted by rocky areas acting as a heat source during the night. The selection of rocky areas was more important in the first months of the active period, when animals emerged from hibernation and started the mating season. At the end of summer, the animals used areas richer in herbs, where insects and other food resources were probably more abundant.