Badger

Morphometric variation in 30 craniometric characters of 465 skulls of the European badgers (Meles meles) from across Europe was analysed. Multivariate analyses revealed that the populations from Norway, Sweden, and Finland differ from other European populations in having smaller skulls. The analyses also revealed significant differences between the ‘south-western Norwegian’ and ‘main Fennoscandian’ forms. On average, badgers from south-west Norway were smaller than those of the remaining Fennoscandia. Morphological differences between the ‘south-western Norwegian’ and ‘main Fennoscandian’ populations of M. meles suggest a possible in situ semisympatric divergence since the beginning of the Holocene warming, or a complex history of two groups involving at least two colonization routes. The small-sized Scandinavian badgers may be close to the ancestral form that used to be widespread in Denmark and throughout Europe. The animals from south-west Norway may instead be descendants of ancestors that were the first to penetrate the southern parts of the Scandinavian Peninsula. The ‘main Fennoscandian’ badgers are likely to have been the descendants of the second wave of recolonization of Scandinavia. Specifically, they might have colonized the Scandinavian Peninsula from the east after the last glaciation.

An analysis of 30 craniological characters of Eurasian badgers (Meles spp.) revealed different levels of sexual size dimorphism (SSD) and geographic variation in the three different species. SSD is displayed mostly in the general size of the skull (condylobasal length, zygomatic width, width of rostrum, and cranial height) and mandible (height of the vertical mandibular ramus, total length of the mandible, and length between the angular process and infradentale), and in some dental characters (length of the upper molar M1). The most stable size dimorphism is manifested in the size of the canines, which is pronounced in all studied samples. SSD is not apparent in the length of the auditory bulla, the postorbital width, the minimum palatal width, the length of the lower molar M2, and the talonid length of the lower carnassial tooth M1.In both the European badgers, Meles meles, and the Asian badgers, Meles leucurus, two geographic forms that differ in the degree of SSD have been found. The most pronounced SSD of cranial characters is found in the Transcaucasian form of Meles meles and the Far-Eastern form of Meles leucurus. In the large European form of Meles meles, SSD is less pronounced in both absolute and relative criteria than in the smaller Transcaucasian form. An analogous situation is observed in the larger Siberian and smaller Far-Eastern forms of Meles leucurus. In the Japanese badgers, Meles anakuma, a downsizing of the skull is accompanied by a decrease in SSD (except in canine size) in comparison to the continental species. The significant differences in the manifestation of SSD in the Eurasian badgers support an earlier hypothesis (Abramov, 2001. Proc. Zool. Inst. Russ. Acad. Sci. 288, 221–233; Abramov, 2002. Russ. J. Theriol. 1 (1), 57–60; Abramov, 2003. Small Carnivore Conserv. 29, 5–7) that Meles meles, Meles leucurus, and Meles anakuma are separate species. The differences in the level of SSD among and within these three species of badgers may be attributed not to differences in the diet or social structure, but to the history of speciation events and formation of intraspecific distribution ranges.

The principal aim of this research was to study coarsescale habitat selection and distribution of main setts of the Eurasian badger (Meles meles L., 1758). The study area extends for 161 Km2 in the hilly territory of southern Lombardy (Italy). The positions of 23 main setts (SP) and 28 random points (RP) were mapped into a GIS. For each point, several environmental characteristics were measured in the field or taken from thematic digital maps. A statistical comparison of the distribution of these characteristics in a circular area (radius 300 m) around each point was carried out. Eurasian badger setts were primarily dug in sheltered places, with high tree cover. The Manly selection index pointed to a strong selection for deciduous woods. Southern slope orientation and the presence of chestnut trees, a potentially important resource for badgers in this area, were also preferred. Similar to other studies, geological and lithological characters and the distance from water did not appear to influence den use. However, the substratum of the study area was mainly formed with sedimentary rocks, loam rocks and sandstones, with also easy-to-dig alluvial soils. Water is a resource easily available over the whole territory, with a well-branched network of rivers and streams. The road network and the presence of urban or industrial infrastructures seem to be a real factor of danger and disturbance, as one of the leading causes of mortality for badgers are road casualties. Our results suggest that badgers of this region are more selective for the sett site than for food resources.