Abstract 162 – A country divided: how barriers affect the gene flow of apex predator in Slovakia

Jana Šrutová, Nikola Tkáčová, Barbora Černá Bolfíková, Michal Kalaš, Mária
Apfelová, Dušan Romportl, Kristýna Vlková, Marián Hletko, Vladimír Antal, Slavomír Finďo,
Pavel Hulva

The brown bear (Ursus arctos) is currently the largest apex predator in Europe. This species
occupies an important position in ecological networks and is often referred to as a keystone,
umbrella, and flagship species. Like populations of other large carnivores, the European brown
bear population has been radically fragmented over the past centuries due to intensive hunting
and lack of protection. Based on more than 2,000 mostly non-invasive samples collected mainly
in the Western Carpathians between 2019 and 2021 and using a microsatellite panel, a
population structure that includes several genetic clusters was determined. This may be related
to the occurrence of refugia in isolated mountain ranges in Slovakia, which may have led to
genetic diversification of individual subpopulations. By linking landscape genetic and geographic
habitat modeling analyses, the main natural and anthropogenic barriers to gene flow were
identified. Currently, Slovak bear populations face not only natural barriers to gene flow related
to the sky island model, but also the increasing impact of anthropogenic barriers, which may
facilitate genetic differentiation. Examples include the construction of linear infrastructure in
valleys between orographic units and along major rivers. Populations that are geographically
close are thus genetically relatively distant. These findings can also serve as a basis in the
applied sphere for ensuring the viability of the population not only of the brown bear in
Slovakia.