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Agricultural intensification has led to a dramatic impoverishment of biodiversity. Moths are not an exception: rapid declines of common and widespread species have been reported and it is still not clear which conservation measures should be applied to restore their populations.We investigated how much of the variation in moth assemblages inhabiting extensively managed meadows in a region of high‐intensity agriculture is explained by surrounding woody landscape features, meadow management and vegetation composition, and which specific variables are the most influential.Results show that the percentage of forest and the length of hedgerows within a 250 m radius were especially important for forest macromoths, explaining 42% of variation in abundance and 23% of species richness, whereas meadow management played a relatively marginal role. The abundance of grassland macromoths was also positively influenced by the length of hedgerows in the landscape (combined with elevation it explained 10% of the variance), while it responded negatively to uncut refuge and to delayed mowing (7%). Regarding grassland macromoth species richness, the annual harvesting frequency was the main predictor (4%). In contrast, micromoth abundance was more influenced by meadow management, notably the date of the first cut (4%) and vegetation composition (8%, though not conclusive due to a single outlier), whereas landscape features explained nothing.Altogether, these results demonstrate the importance of both woody features within farmed landscapes and biodiversity‐friendly meadow management for the maintenance of integral moth communities. [ABSTRACT FROM AUTHOR]

Sown wildflower strips can support insects that collect pollen for their larvae. How these strips affect flower visitors with carnivorous larvae, however, is almost unknown. We studied the impact of wildflower strips and their surroundings on two common solitary wasps: the caterpillar-hunting Ancistrocerus nigricornis Curtis and the spider-hunting Trypoxylon figulus Linnaeus., Trap-nest locations at 22 semi-natural habitats in central Germany formed independent gradients in landscape complexity and distance to either one or several wildflower strips in their surroundings. For each brood cell, we recorded the number of prey items, total caterpillar weight and spider species richness., Ancistrocerus nigricornis built more cells in proximity to wildflower strips and with increasing amount of surrounding grassland. Fewer prey items provided in landscapes with large shares of semi-natural habitats suggest that in these landscapes high-quality prey is available. In contrast, T. figulus built more cells with increasing distance of nests to wildflower strips. If there were few strips, T. figulus built more cells in grassland-rich landscapes, whereas low shares of grassland were compensated when several wildflower strips were present. Benefits of flowering strips for T. figulus seem related to flower resources for adults, rather than through prey provisioning., In conclusion, wildflower strips promote prey-hunting wasps through species-specific effects on adult and larval food provisioning. Considering the differential effects of wasps on crop pests (caterpillars) and natural enemies (spiders), the functional role of wildflower strips in agroecosystems may be much greater than assumed when solely focusing on pollination. [ABSTRACT FROM AUTHOR]

Mitigation tools aimed at counteracting the loss of farmland insect diversity and associated ecosystem services are usually conducted on cultivated fields. Possibilities of managing field-forest ecotones for biodiversity have been rarely discussed, despite their importance for flower-visiting insects., The effectiveness of logging in enhancing three aspects of insect diversity (bumblebee abundance, total species richness, and habitat specialist butterfly abundance) and changes in insect community composition were studied in a three-year field experiment. The study included 15 field-forest ecotones, each with a 50 m long and 25 m wide treated area and a corresponding control. At forest edge, a 5 m wide strip was clear-cut and behind this strip, a 20 m wide belt was thinned to a basal area of 8 m2 ha−1., Logging simultaneously promoted all three aspects of insect diversity. Changes were more apparent at clear-cut edge than in the thinned interior. Community composition changed via increased abundance of open habitat species, especially butterflies., Logging promoted warm microclimates and flower availability at clear-cut edges. All three aspects of insect diversity showed a positive response to flower coverage, which in turn was negatively correlated with the amount of logging residue., Creating open field-forest ecotones is beneficial for flower-visiting insects and open habitat species in particular. This approach is expected to be most beneficial at sunny forest edges and sites which become overgrown slowly. In addition, we suggest logging residue to be removed when aiming to promote flower-visitors. [ABSTRACT FROM AUTHOR]