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Light pollution is a major threat to biodiversity worldwide. There is a crucial need to elaborate artificial lighting recommendations to mitigate its impact on wildlife. In the present study, we investigated how streetlight spatial position and light trespass impacted the use of ecological corridors by transiting bats in anthropogenic landscapes. Through a paired, in situ experiment, we estimated how streetlight distance of impact and vertical and horizontal illuminance influenced the transiting activity of 6 species and 2 genera of bats. We selected 27 pairs composed of 1 lit site and 1 control unlit site in areas practicing either part-night or full-night lighting. We recorded bat activity at 0, 10, 25, 50 and 100 m, and measured vertical and horizontal light illuminance at the 5 distance steps (range = 0.1–30.2 lx). While streetlight attraction effect was mostly limited to a 10 m radius for Pipistrellus sp. and Nyctalus sp., streetlight avoidance was detected at up to 25 and 50 m for Myotis sp. and Eptesicus serotinus , respectively. Streetlight effects on Myotis sp. and Nyctalus sp. remained after lamps were turned-off. Illuminance had a negative effect on Myotis sp. below 1 lx, a mixed effect on E. serotinus , and a positive effect on the other species, although a peak of activity was observed between 1 and 5 lx for P. pipistrellus and N. leisleri. We recommend separating streetlights from ecological corridors by at least 50 m and avoiding vertical light trespass beyond 0.1 lx to ensure their use by light-sensitive bats. [ABSTRACT FROM AUTHOR]

As light pollution is currently considered to be a major threat to biodiversity, different lighting management options are being explored to mitigate the impact of artificial lighting on wildlife. Although part-night lighting schemes have been adopted by many local authorities across Europe to reduce the carbon footprint and save energy, their effects on biodiversity are unknown. Through a paired, in situ experiment, we compared the activity levels of 8 bat species under unlit, part-night, and full-night lighting treatments in a rural area located 60 km south of Paris, France. We selected 36 study locations composed of 1 lit site and a paired unlit control site; 24 of these sites were located in areas subject to part-night lighting schemes, and 12 sites were in areas under standard, full-night lighting. There was significantly more activity on part-night lighting sites compared to full-night lighting sites for the late-emerging, light-sensitive Plecotus spp., and a similar pattern was observable for Myotis spp., although not significant. In contrast, part-night lighting did not influence the activity of early emerging bat species around streetlights, except for Pipistrellus pipistrellus for which there was significantly less activity on part-night lighting sites than on full-night lighting sites. Overall, no significant difference in activity between part- and full-night lighting sites were observed in 5 of the 8 species studied, suggesting that current part-night lighting schemes fail to encompass the range of activity of most bat species. We recommend that such schemes start earlier at night to effectively mitigate the adverse effects of artificial lighting on light-sensitive species, particularly along ecological corridors that are especially important to the persistence of biodiversity in urban landscapes. [ABSTRACT FROM AUTHOR]

Farmland biodiversity continues to decline mainly because of agricultural intensification and land abandonment. Agri-environment schemes can be designed to halt this loss by favouring extensification of agricultural practices and through sympathetic management of field boundaries and fallow land. In Europe, High Nature Value (HNV) farmland is defined as low-intensity farmland supporting or associated with a high rate of biodiversity, in terms of species richness or habitat diversity and therefore plays a crucial role in the maintenance of European biodiversity. However, no large-scale analysis has explored the role of these areas in achieving conservation goals. We analysed information from widely used indicators in order to describe the impact of low-intensity agriculture on farmland biodiversity in France. We used the HNV farmland indicator, based on agricultural statistics such as the Farm Structure Survey and the grassland survey, and common bird indicators, i.e. the Farmland Bird Indicator (FBI), the Community Specialization Index (CSI) and species richness indexes, based on the French Breeding Bird Survey. Temporal trends in the farmland bird indicator showed that populations of farmland birds were more likely to increase inside HNV areas compared to non-HNV areas. Although species richness is not higher within HNV farmland, bird communities are composed by more specialist species than in non-HNV areas. In addition, these specialist bird species are significantly more abundant in HNV areas. Synthesis and applications. Further farmland biodiversity decline is potentially reversible through an appropriate management of HNV areas. Existing and future agri-environment schemes should focus on preserving and extending HNV farmland, by favouring the maintenance of low-intensity agriculture and landscape complexity. Priority should be given to preserving diversity at the community level, with the help of adequate indicators, such as the ones presented here. The role of HNV farmland or similar concepts in combining agriculture and biodiversity goals should be further analysed and further used as large-scale conservation tools. [ABSTRACT FROM AUTHOR]

Although positive effects on biodiversity of woody features in agricultural landscapes are widely recognized, questions remain as to which landscape context to prioritize their implementation and in what proportion. To investigate the response of farmland biodiversity to small woody features (SWF) density in different landscape compositions (cropland, grassland, mixed), we analyzed fine-resolution data from standardized monitoring schemes on 111 birds, 22 bats, and 25 bush cricket's species, at national scale (relying on 3772, 834 and 727 monitoring points) over the period 2015–2019, in metropolitan France. We used Generalized Additive Mixed Models to analyze population and community responses, through different metrics (abundance, species diversity, and functional composition). We found a positive response exhibited by the three taxa to SWF, more especially in cropland where the SWF density is the lowest relative to grassland and mixed landscapes. Also, our results suggested a non-linear response common to the three taxa, with an increased benefit up to at least 6 % of SWF density in cropland, and beyond for most of the metrics but to a lesser extent (e.g., maximum abundance reached at 7–12 % SWF). We note, however, that some species among farmland bird specialists are negatively impacted by SWF. Overall, we emphasize the benefits to promote woody features in agricultural landscapes, notably in cropland, to support biodiversity and its associated ecosystem functions. Our study provides crucial empirical evidence to the recommendations from previous studies and the relevance of the EU Biodiversity Strategy for 2030 to dedicate at least 10 % of farmland to high-diversity landscape features. [ABSTRACT FROM AUTHOR]