Multisource noninvasive genetics of brown bears (Ursus arctos) in Greece reveals a highly structured population and a new matrilineal contact zone in southern Europe

In human-dominated landscapes, connectivity is crucial for maintaining demographically stable mammalian populations. Here, we provide a comprehensive noninvasive genetic study for the brown bear population in the Hellenic Peninsula. We analyze its population structuring and connectivity, estimate its population size throughout its distribution, and describe its phylogeography in detail for the first time. Our results, based on 150 multilocus genotypes and on 244-bp sequences of the mtDNA control region, show the population is comprised by three highly differentiated genetic clusters, consistent with geographical populations of Pindos, Peristeri, and Rhodope. By detecting two male bears with Rhodopean ancestry in the western demes, we provide strong evidence for the ongoing genetic connectivity of the geographically fragmented eastern and western distributions, which suggests connectivity of the larger East Balkan and Pindos-Dinara populations. Total effective population size (N e) was estimated to be 199 individuals, and total combined population size (N C) was 499, with each cluster showing a relatively high level of genetic variability, suggesting that migration has been sufficient to counteract genetic erosion. The mtNDA results were congruent with the microsatellite data, and the three genetic clusters were matched predominantly with an equal number of mtDNA haplotypes that belong to the brown bear Western mitochondrial lineage (Clade 1), with two haplotypes being globally new and endemic. The detection of a fourth haplotype that belongs to the Eastern lineage (Clade 3a1) in three bears from the western distribution places the southernmost secondary contact zone between the Eastern and Western lineages in Greece and generates new hypotheses about postglacial maxima migration routes. This work indicates that the genetic composition and diversity of Europe's low-latitude fringe population are the outcome of ancient and historical events and highlight its importance for the connectivity and long-term persistence of the species in the Balkans.

Wolf diet and livestock selection in central Greece

Understanding the feeding habits of wolves is essential for designing and implementing fundamental management processes across the range of the species. This is even more important within human-dominated areas, such as southern Europe, and more especially Greece. In this context, we analyzed 123 scat samples, collected between 2010 and 2012, from a mixed agricultural, forested and human-dominated area, centered on the municipality of Domokos in central continental Greece. We used standard laboratory procedures for scat analysis and calculated percentages of frequency of occurrence (FO%), average volume (AV%) and biomass index (BM%) to assess diet composition, and estimated prey selectivity. Domestic prey composed the bulk of wolf diet (FO%=73.5, AV%=84.8, BM%=97.2), wild ungulates were almost absent (FO%=0.5, AV%=0.8, BM%=1.2), whereas grass consumption was high in our area (FO%=19.5, AV%=11.0). The high dependence on livestock corroborates previous studies from Greece and other countries in southern Europe. Goat (FO%=46.0, AV%=61.2, BM%=64.9) was the main prey and was strongly selected, with sheep (FO%=11.5, AV%=9.0, BM%=11.2), pig carrion and cattle ranking behind (FO%=11.5, AV%=10.1, BM%=8.7 and FO%=4.5, AV%=4.5, BM%=12.4, respectively). No differences across seasons were detected, except from pig carrion, which increased during winter. The preference for goats is probably associated with its grazing behavior. High livestock consumption generally results in increased human-wolf conflict. Thus, substantial improvement of husbandry practices and restoration of wild ungulate populations are recommended to facilitate wolf-human coexistence in Greece.