Livestock grazing is a key factor in many grassland ecosystems and can substantially influence the conservation of grassland species. The Crau steppe in southern France is a protected area that is traditionally grazed by sheep. The Critically Endangered Crau plain grasshopper Prionotropis rhodanica is endemic to the area and a flagship for the conservation of this unique ecosystem. Its population has declined significantly during the last 2 decades, but the reasons remain poorly understood. One potential factor is an altered habitat structure caused by changes in the grazing regime. We examined the microhabitat preferences of the species and compared the habitat structure of populated sites with those where the species is now extinct (former habitat). We found that populated sites had denser and higher vegetation, whereas former habitat had higher cover of stones and bare ground. Vegetation structure in the habitat of the smallest subpopulation was similar to areas of former habitat, suggesting a marginal habitat quality. Our results show that P. rhodanica requires 50–70% vegetation cover and suggest that grazing has contributed considerably to the population decline, but it remains unclear whether this is a direct effect of habitat degradation or an indirect effect by attracting predators associated with grazing activities. We recommend careful management of grazing to improve habitat quality, which would also benefit other invertebrates and insectivores. Continued monitoring is required to conserve habitat specialists in protected areas.

Dry, oligotrophic ecosystems are highly threatened in Europe due to massive changes in land use and eutrophication. The conservation of these xeric habitats has received much attention, whereas the ecotones between xeric habitats and other habitat types are often disregarded. One species which mainly inhabits the transition zone between pine forests and adjacent xeric habitats is the heath grasshopper, Chorthippus vagans. This species is endangered in large parts of Europe. One of the largest populations in northern Germany is found on a degraded inland dune near Hanover. This population is threatened by dense growth of deciduous trees and litter accumulation. We analyzed changes in the distribution of this population after the implementation of conservation measures (thinning out the forest and removal of leaf litter). Moreover, we examined dispersal distances of the species in order to assess its colonization potential. We also studied the microhabitat preferences of C. vagans to assess key factors influencing its local distribution. Our data show a substantial growth in population size, which might be a consequence of the conservation measures. New patches on the dune were colonized, promoting dispersal between the subpopulations. We propose that restoration of forest-dune ecotones should be considered more often in landscape planning and conservation management.

Fire has become a frequent tool in nature conservation and hazard reduction, but there is still dispute about the responses of many taxa, especially concerning invertebrate populations. While the effects of fire on plants and animals have been examined intensively in prairies, savannahs and coniferous forests, wetlands have rarely been considered in this context, yet wetland ecosystems do experience periodic fires. This study examines the effects of prescribed burning and wildfires on Orthoptera in four Central European peat bogs. All species persisted on the burned plots and none experienced a massive decline in abundance compared to unburned treatments. Generally, differences in species composition and abundance were more distinct between the bogs than between the fire treatments or fire season. One threatened species, Omocestus rufipes, occurred more often in burned than in unburned samples. The abundances of Orthoptera species in the transition zone between burned and unburned plots were either uniform or step-like rather than gradual in nature, conflicting with a hypothesis of post-fire recolonization from unburned plots. This pattern supported by non-metric multidimensional scaling suggests that the vegetation structure plays a substantial role in habitat choice of these insects. Small-scale fires between February and May do not seem to represent a threat to Orthoptera species. However, in the longer term, peat bog restoration may be affected by negative vegetation responses.