Hotspots of the Habitats Directive Species in the Carpathians

Knowledge of species distribution is crucial for their protection, and this was our motivation to identify hotspots of the Habitats Directive (HD) species in the Carpathians. As a data source we used reports and species distribution maps submitted by the EU Member States according to the Habitats Directive Article 17 in 2019.The highest HD species richness areas are in the south-eastern part of the Western Carpathians and in the south-west outcrops of the Carpathians at the SK/AT and CZ/AT borders. The south-eastern part of the Western Carpathians is important for all studied species groups, specific patterns of distribution exhibit fish (distribution along big rivers), amphibians (high diversity also in the outer Western Carpathians and Transylvanian Basin) and partially plant species (besides SE Western Carpathians, quite high diversity also in other parts of the Western Carpathians).We analysed the relation between species richness, proportion of species groups, and concentration of rare species. Mammals are the dominant taxonomical group, especially in species-poor grid cells. The proportion of invertebrates increases with increased species richness. The widespread species prevail in species-poor grid cells and their proportion decreases with increasing species richness.We also identified areas with low Natura 2000 coverage, but with high biodiversity or a high number of rare species. These areas have high potential to improve protection of the HD species by designating new Natura 2000 sites or enlarging existing ones.