The geography of high-value biodiversity areas for terrestrial vertebrates in Western Europe and their coverage by protected area networks

We identified high-value biodiversity areas (HVBAs) of terrestrial vertebrates according to a combined index of biodiversity (CBI) for each major taxon and a standardized biodiversity index (SBI) for all taxa in 2195 cells of 50 × 50 km in Western Europe to evaluate whether these areas are included in the current protected area networks. The World Database on Protected Areas (WDPA) and NATURA 2000 protected area network were used to assess the protected area cover in HVBAs. WDPA and NATURA 2000 were geographically quite complementary as WDPA is more densely represented in Central and Northern Europe and NATURA 2000 in the Mediterranean basin. A total of 729 cells were identified as HVBAs. From the total of these HVBA areas, NATURA 2000 network was present in more cells (660) than the WDPA network (584 cells). The sum of protected land percentages across all the HVBA cells was 28.8 %. The identified HVBA cells according to the SBI included 603 or 78.2% of all vertebrate species in the study region, whereas the identified HVBA cells according to the SBI for individual taxa included 47 (90.4 %) species of amphibians, 79 (74.5 %) of reptiles, 417 (88.5 %) of birds, and 130 (91.5 %) of mammals. However, neither network was present in 7 or 3% of the identified HVBA cells. Thus, we recommend expanding protected areas in Europe to fill this gap and improve coverage of vertebrate species to strengthen biodiversity conservation.