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Central European calcareous grasslands are particularly rich in species, harbouring an endangered flora and fauna. In this study, we analyse how invertebrates, like ground beetles, react on vegetation changes in these habitats. We ask if and how species of both groups may react on local environmental changes associated with conservation management regimes. For this reason, vascular plant and ground beetle communities were assessed at six semi-natural calcareous grasslands in Luxembourg before (1988–1992) and after (2008–2010) restoration had started. All studied grassland sites are protected as nature reserves and managed to preserve an open and diverse plant species composition. Our data indicate diverging trends for plant and ground beetle composition: Richness and abundance of species increased for plants and decreased for ground beetles, particularly for forest and Red List species. Functional diversity of plants and ground beetles remained stable, although the abundance of nitrogen-loving plant species increased. In ground beetles, we identified increased proportions of species with strong habitat associations. These findings underline that plant species, in particular typical calcareous grassland species, benefited from ongoing conservation management, while many ground beetle species, mostly the non-grassland specialists, suffered under the applied management regimes. These results highlight the general dilemma in nature conservation of how to prioritise management regimes in situ.

Thickets along rivers in Eastern Kenya are important habitats for many endangered species. These habitats also provide fundamental ecosystem services for humans. Intense anthropogenic activities during the past decades have caused a severe reduction of this vegetation and resulted in fragmentation of the remaining thicket patches. We assessed the occurrence of the Kenyan endemic bird species Hinde's Babbler (Turdoides hindei) in a highly fragmented environment and performed detailed land use mapping along the Nzeeu River in East Kenya. We measured the time the birds spent in thicket patches, which differed in their habitat setting: pristine versus surrogate vegetation, different habitat size and different edge-size-ratio. Further, we identified areas of potential conflicts between human activities and our target species. Four T. hindei family groups were observed, mostly in invasive Lantana camara patches. Habitat size and edge-size-ratio of the respective thicket patches revealed a significant impact on the duration of stay of T. hindei with disproportional longer stays in small habitat patches and in patches with larger edge-size-ratio than in rather large patches or thickets with small edge-size-ratio. The 75%- and 95%-kernels showed no overlap between family groups and only marginal overlap with the 75%-kernels of human disturbances. Our data show that the invasive L. camara thickets (even small patches with high edge-size ratio) are a suitable surrogate habitat for the Kenyan endemic for T. hindei. The birds avoid open land likely because of higher predation pressure outside of thickets. Limited overlap between zones of human activity and the occurrence of T. hindei may be a response either to lacking thickets in these areas, and/or an adaptation to elevated hunting pressure in these zones. Therefore, the transformation of thickets into open agricultural land has a negative impact on the persistence of T. hindei. For the preservation of the remaining T. hindei family groups in our study area we suggest to establish an interconnected network of thicket patches, as the high mobility of the species allows persistence in such patchy environments.

Oligotrophic calcareous grasslands are among the most species-rich habitats in temperate Europe. Land use changes caused a severe decline of these species-rich grasslands over the last decades. Today, these ecosystems exist as highly isolated and small remnants being threatened by abandonment, afforestation and the transformation into agricultural land. Local conservation activities caused changes in habitat structures within such oligotrophic calcareous grasslands and their often isolated character may have led to stochastic species extinctions due to population fluctuations. In this study we focus on potential changes of grassland biota over the past decades. We analyse retrospective species inventories (14 for carabid beetles and 7 for butterflies) from calcareous grasslands located in western Germany with adjoining parts of Luxembourg over a period from 1972 to 2011. Our data indicate two distinct temporal cohorts (past versus present) that differ strongly in the composition and structure of carabid beetles and butterfly communities. Patterns of species co-occurrences tended to be segregated in the past communities while the co-occurrences in recent communities were either random or aggregated. β-Diversity increased with time. Our results indicate a temporal shift from past communities dominated by species interactions towards recent neutral assemblages. These changes might be caused by diverging conservation management being restricted to local sites. This resulted in a higher diversity of environmental structures combined with a loss of grassland habitats and declining matrix permeability. However, we detected no loss of rare carabid beetles, while butterflies showed severe extinctions of species with specific habitat demands, high endangerment and/or low dispersal behaviour. These trends let us argue that carabid communities mirror local changes in habitat structure (caused by conservation action), while butterflies show additional effects due to environmental stochasticity, local extinctions and a subsequent lack of re-colonization from adjoining populations.