Are there differences in the morphology of communal mounds of overwintering mound-building mice (Mus spicilegus Petényi, 1882) in Slovakia?

Abstract

To describe variations in overwintering mounds and nest sizes of the mound-building mouse (Mus spicilegus), mounds were measured and excavated in 16 locations in south-eastern and south-western Slovakia in autumn and/or winter between 2002 and 2011. The study was carried out in fields where crops had been harvested before the investigations. All evaluated mounds were located in agroecosystems with sunflower, maize and wheat crops as well as on field margins. Comparisons were made by basis of their dimensions (length, width, height, volume, nest depth) and the plant material collected. Data between the sampling groups were compared using the Mann-Whitney U test and Kruskal-Wallis H test. Spearman’s correlation (rs) was used to examine the relation between mound and nest size (dependent variables) and four independent variables (season, geomorphological, soil and field types). We found habitat and soil-related variation in mound size which also diminished by season. Mounds vary in size among geographical populations, i.e. mounds from south-eastern Slovakia (basin and lowland) had larger dimensions than those from south-western Slovakia (upland). In contrast, we didn’t confirm a correlation between the sizes of the mounds and the nests.