Airports for the genetic rescue of a former agricultural pest.

The intensification of agricultural practices and urbanisation are widespread causes of biodiversity loss. However, the role of artificial habitats in genetic rescue is an aspect that is not well understood. Implementing genetic rescue measures to improve gene flow and maintain a viable population of keystone species is a crucial prerequisite for promoting diverse and resilient ecosystems. Landscape fragmentation and modern agricultural methods have caused the decline and the isolation of the remnant colonies of the endangered European ground squirrel (Spermophilus citellus) throughout its range. However, the artificial habitat, such as airport fields with regular grass mowing, provides suitable conditions for this grassland specialist. We measured home range size and genetic variation of seven souslik colonies in western Slovakia. Based on the 6904 ddRAD SNPs, we found significantly higher individual heterozygosity in colonies on airports compared to colonies on pastures. This indicates a potential for higher fitness of individuals from airport colonies, which can serve as a source for evidence-based translocations. Such an intervention can preserve the genetic diversity of small and isolated populations in the region. We emphasize that conservation management strategies would be strengthened including a specific focus on human-made grassland habitats.

Monitoring of species' genetic diversity in Europe varies greatly and overlooks potential climate change impacts.

Genetic monitoring of populations currently attracts interest in the context of the Convention on Biological Diversity but needs long-term planning and investments. However, genetic diversity has been largely neglected in biodiversity monitoring, and when addressed, it is treated separately, detached from other conservation issues, such as habitat alteration due to climate change. We report an accounting of efforts to monitor population genetic diversity in Europe (genetic monitoring effort, GME), the evaluation of which can help guide future capacity building and collaboration towards areas most in need of expanded monitoring. Overlaying GME with areas where the ranges of selected species of conservation interest approach current and future climate niche limits helps identify whether GME coincides with anticipated climate change effects on biodiversity. Our analysis suggests that country area, financial resources and conservation policy influence GME, high values of which only partially match species' joint patterns of limits to suitable climatic conditions. Populations at trailing climatic niche margins probably hold genetic diversity that is important for adaptation to changing climate. Our results illuminate the need in Europe for expanded investment in genetic monitoring across climate gradients occupied by focal species, a need arguably greatest in southeastern European countries. This need could be met in part by expanding the European Union's Birds and Habitats Directives to fully address the conservation and monitoring of genetic diversity.

Assessment of drivers of spatial genetic variation of a ground-dwelling bird species and its implications for conservation.

In modern wildlife ecology, spatial population genetic methods are becoming increasingly applied. Especially for animal species in fragmented landscapes, preservation of gene flow becomes a high priority target in order to restore genetic diversity and prevent local extinction. Within Central Europe, the Alps represent the core distribution area of the black grouse, Lyrurus tetrix. At its easternmost Alpine range, events of subpopulation extinction have already been documented in the past decades. Molecular data combined with spatial analyses can help to assess landscape effects on genetic variation and therefore can be informative for conservation management. Here, we addressed whether the genetic pattern of the easternmost Alpine black grouse metapopulation system is driven by isolation by distance or isolation by resistance. Correlative ecological niche modeling was used to assess geographic distances and landscape resistances. We then applied regression-based approaches combined with population genetic analyses based on microsatellite data to disentangle effects of isolation by distance and isolation by resistance among individuals and subpopulations. Although population genetic analyses revealed overall low levels of genetic differentiation, the ecological niche modeling showed subpopulations to be clearly delimited by habitat structures. Spatial genetic variation could be attributed to effects of isolation by distance among individuals and isolation by resistance among subpopulations, yet unknown effects might factor in. The easternmost subpopulation was the most differentiated, and at the same time, immigration was not detected; hence, its long-term survival might be threatened. Our study provides valuable insights into the spatial genetic variation of this small-scale metapopulation system of Alpine black grouse.