Habitat quality of wildflower strips for common voles (Microtus arvalis) and its relevance for agriculture

Ecological compensation areas have been widely promoted in agriculture in the last decade. Besides their positive effects on biological diversity they also bear a risk of sheltering potential pest species such as common voles (Microtus arvalis). To assess the influence of wildflower strips on the spatio-temporal behavior of voles and their impact on adjacent crop fields, a common vole population living in a wildflower strip was monitored from May to October 2000 and from March to September 2001. A new system for automatic radio tracking was used which allowed tracking at 1 min intervals and up to 1000 bearings per vole per day. Voles showed small home ranges with a median size of 125 m2 (minimum convex polygon) and 30 m2 (Kernel), respectively. Home ranges were stable with a median overlap of 90% for consecutive days, were almost exclusively within the wildflower strip and contained several core areas per range. A polyphasic activity pattern with a phase length of 1.7 h was found during summer with a trend towards diurnal activity. Overall wildflower strips were high-quality habitats for voles and sustained high population densities without increased risk of voles dispersing into adjacent fields.