The use of artificial nest-boxes by Apodemus sylvaticus dichrurus in Sicily

Reports of wood mouse arboreality are rather scarce outside Britain. I reviewed and analysed 267 visits and 16.456 checks of glirids artificial nest-boxes mounted on trees, in twelve sample areas of Meso- and Supra-Mediterranean woodlands (Sicily, 1995-2005). The wood mouse was recorded only 65 times (0.395%) using the artificial nest-boxes in nine sample areas, and based on this low frequency, the wood mouse can be considered as an occasional dweller of artificial nest-boxes. The resource selection index allowed checking the use respect to the availability of nest-boxes placed at different heights. These were likely reached by climbing the dense understorey and low tree branches up to 5 m, but nest-boxes in the two lower classes (0.5-1.0 and 1.1-1.5 m) were used more than those in the two higher classes (1.6-2.0 and 2.1-5.0 m). ANOVA results suggested that the box use was not related to any particular habitat or sample area feature, and it was slightly more pronounced from March to May. Regardless of their age and sex, individuals mostly exploited nest-boxes placed near the ground (0.5-1.5 m) and generally for 2-3 months. Nonetheless, cases of consecutive use for longer periods and instances of reproduction inside nest-boxes showed that some individuals extended their home range also to the vertical dimension.