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The effectiveness of organic farming on biodiversity has been widely documented especially for plants, arthropods and birds; however, the effects of the transition period required to become an organic farm on wildlife remain poorly understood.We assessed the effects of organic farming on insectivorous bats in citrus orchards in the Republic of Cyprus employing two matched designs (conventional vs. 3‐year organic‐transitional and conventional vs. organic‐certified) and a third unmatched design (3‐year organic‐transitional vs. organic‐certified). We specifically investigated whether the transition period prior to full organic certification influenced bat activity with a special focus on any moderation effects from surrounding semi‐natural areas.The activity of three (Pipistrellus kuhlii, Hypsugo savii and Miniopterus schreibersii) of four bat species was significantly lower in farms undergoing the transitional period than in conventional farms, and P. kuhlii and H. savii were significantly less active in organic transitional farming systems that in organic‐certified ones. Furthermore, the activity of the most dominant species (P. kuhlii) was significantly higher on organic than transitional and conventional citrus orchards, thus suggesting a time‐lag effect. Landscape complexity measured as the amount of semi‐natural areas did not moderate the effects of farming system for any study species.Synthesis and application. The transition to organic farming had persistent detrimental effects on bats and potentially on the pest suppression services they provide. Future agri‐environmental policy should consider the transition period and implement measures to mitigate any negative effects on biodiversity, alongside promoting asynchronous transition of nearby farms. Our findings further highlight the crucial need to consider the time since transition to organic farming when assessing potential benefits of organic management on biodiversity. [ABSTRACT FROM AUTHOR]

Renewable energy is growing at a rapid pace globally but as yet there has been little research on the effects of ground‐mounted solar photovoltaic (PV) developments on bats, many species of which are threatened or protected.We conducted a paired study at 19 ground‐mounted solar PV developments in southwest England. We used static detectors to record bat echolocation calls from boundaries (i.e. hedgerows) and central locations (open areas) at fields with solar PV development, and simultaneously at matched sites without solar PV developments (control fields). We used generalised linear mixed‐effect models to assess how solar PV developments and boundary habitat affected bat activity and species richness.The activity of six of eight species/species groups analysed was negatively affected by solar PV panels, suggesting that loss and/or fragmentation of foraging/commuting habitat is caused by ground‐mounted solar PV panels. Pipistrellus pipistrellus and Nyctalus spp. activity was lower at solar PV sites regardless of the habitat type considered. Negative impacts of solar PV panels at field boundaries were apparent for the activity of Myotis spp. and Eptesicus serotinus, and in open fields for Pipistrellus pygmaeus and Plecotus spp.Bat species richness was greater along field boundaries compared with open fields, but there was no effect of solar PV panels on species richness.Policy implications: Ground‐mounted solar photovoltaic developments have a significant negative effect on bat activity, and should be considered in appropriate planning legislation and policy. Solar photovoltaic developments should be screened in Environmental Impact Assessments for ecological impacts, and appropriate mitigation (e.g. maintaining boundaries, planting vegetation to network with surrounding foraging habitat) and monitoring should be implemented to highlight potential negative effects. [ABSTRACT FROM AUTHOR]

With the ever-increasing dependency on electric power, electrical grid networks are expanding worldwide. Bats exhibit a wide diversity of foraging and flight behaviours, and their sensitivity to anthropogenic stressors suggests this group is very likely to be affected by power lines in a myriad of ways. Yet the effects of power lines on bats remains unknown. Here we assessed the responses of insectivorous bats to very high voltage power lines (VHVPL; greater than 220 kV). We implemented a paired sampling design and monitored bats acoustically at 25 pairs, one pair consisting of one forest edge near to VHVPL matched with one control forest edge. Relative humidity mediates the effects of power lines on bats: we detected bat attraction to VHVPL at high relative humidity levels and avoidance of VHVPL by bats at low relative humidity levels. We argue that the former could be explained by insect attraction to the light emitted by VHVPL owing to corona discharges while the latter may be owing to the physical presence of pylons/cables at foraging height and/or because of electromagnetic fields. Our work highlights the response of bats to power lines at foraging habitats, providing new insight into the interactions between power lines and biodiversity. [ABSTRACT FROM AUTHOR]

Wind power generation has grown exponentially over the past 20 years to meet international goals of increasing the share of renewables in energy production. Yet, this process has too often been conducted at the cost of airborne biodiversity such as birds and bats. The latter are severely threatened due to deaths by collision at wind turbine. The UNEP/EUROBATS agreement that came into force in 1994 is now ratified by 37 countries; since 2008, it recommends to site wind turbines at least 200 m away from woody edges to decrease bat fatality risks. However, 14 years later we still do not know to what extent this international recommendation has been applied in Europe. We assessed siting distances between woody edges and wind turbines for the largest wind energy producers among the UNEP/EUROBATS parties: the UK, Germany, and France. We show that 61%, 78%, and 56%, respectively, of the installed wind turbines did not comply with UNEP/EUROBATS guidelines, without improvement over time. We identified probable causes of these findings and provided key policy recommendations to achieve compliance to UNEP/EUROBATS guidelines such as better: (i) inclusion in regulatory texts, (ii) notification of the environmental authorities, and (iii) strategic, well‐informed, forward planning of areas suitable for wind turbine development. [ABSTRACT FROM AUTHOR]

Despite the key importance of the landscape matrix for bats, we still not fully understand how the effect of forest composition interacts at combined stand and landscape scales to shape bat communities. In addition, we lack detailed knowledge on the effects of local habitat structure on bat-prey relationships in forested landscapes. We tested the assumptions that (i) forest composition has interacting effects on bats between stand and landscape scales; and (ii) stand structure mediates prey abundance effects on bat activity. Our results indicated that in conifer-dominated landscapes (> 80% of coniferous forests) bat activity was higher in stands with a higher proportion of deciduous trees while bats were less active in stands with a higher proportion of deciduous trees in mixed forest landscapes (~ 50% of deciduous forests). Moth abundance was selected in the best models for six among nine bat species. The positive effect of moth abundance on Barbastella barbastellus was mediated by vegetation clutter, with dense understory cover likely reducing prey accessibility. Altogether, our findings deepen our understanding of the ecological processes affecting bats in forest landscapes and strengthen the need to consider both landscape context and trophic linkage when assessing the effects of stand-scale compositional and structural attributes on bats. [ABSTRACT FROM AUTHOR]

Mitigating the detrimental impacts of intensive farming on biodiversity requires the implementation of cost‐effective conservation actions. Targeted agri‐environment schemes (AESs) to enhance populations of threatened species inhabiting farmland have been proposed for this purpose, yet their effectiveness for nocturnal wildlife remains unknown.We assessed whether hedgerow management prescribed by targeted AESs to improve habitat conditions for the greater horseshoe bat (Rhinolophus ferrumequinum) in England may positively influence the species, the entire bat assemblage and the insect prey of bats. We specifically investigated the responses of bats (occurrence, activity and species richness) and insects (biomass, abundance and diversity) to time since last trimming (from 1 up to 10 years). We explored the mechanisms underlying the effects of AES via changes in trimming regime on bats. Moreover, we investigated the effects of landscape context on bats as we expected that highly mobile species would benefit further from landscape‐scale management.Bat species richness significantly increased with time since last trimming. Three bat taxa of major conservation concern in Western Europe substantially benefited from the targeted prescription, namely R. ferrumequinum, Rhinolophus hipposideros and Plecotus spp. Insect family richness and dipteran abundance were also significantly greater at hedgerows that were untrimmed for at least 3 years. The activity of more common bat species (i.e. pipistrelle bats) was not influenced by time since last trimming.Changes in trimming regime strongly affected hedgerow height which directly and indirectly (by increasing prey abundance) influenced bat occurrence, activity and species richness along hedgerows.The activity of highly mobile bat species was mainly associated with a range of landscape attributes. The amount of semi‐natural grassland within 0.5 km of the sampling sites positively influenced R. ferrumequinum while the presence of urban areas negatively affected light‐sensitive bat species.Synthesis and applications. The implementation of targeted agri‐environment schemes can include effective measures to enhance bats and their insect prey in farmland. Although we highlight the success of current prescriptions on hedgerow management, we suggest that their effectiveness can easily be optimized by encouraging farmers to keep hedgerows untrimmed for longer periods (>3 up to 10 years). We also highlight that a multi‐scale management approach is required to successfully promote bats in farmland. The implementation of targeted agri‐environment schemes can include effective measures to enhance bats and their insect prey in farmland. Although we highlight the success of current prescriptions on hedgerow management, we suggest that their effectiveness can easily be optimized by encouraging farmers to keep hedgerows untrimmed for longer periods (>3 up to 10 years). We also highlight that a multi‐scale management approach is required to successfully promote bats in farmland. [ABSTRACT FROM AUTHOR]

Efforts to mitigate the climate crisis result in a green‐green dilemma: the development of renewable energy technology is required worldwide to reduce greenhouse gas emissions but can have negative impacts on biodiversity. Impacts are being documented for wind farms, but effects of solar farms (photovoltaic power stations) on habitat use of vertebrates remain extremely poorly known.Using insectivorous bats as a biological model for high trophic levels, we tested whether the presence of ground‐mounted solar farms affected flight and feeding behaviour. We assessed behaviour using three‐dimensional flight path reconstruction systems from echolocation calls, via standardised paired sampling of 16 control and 16 solar farm (treatment) sites. We quantified bat flight and feeding behaviour as flight speed, sinuosity of flight trajectories, and the probability of emission of feeding buzzes (acoustic signatures of prey capture attempts), and demonstrated that feeding was characterised by slow, sinuous flight with feeding buzzes.We recorded 15,273 three‐dimensional bat positions, resulting in 1317 flight trajectories. We found strong behavioural responses to ground‐mounted solar farms in two of three bat guilds and five of seven taxa. Specifically, bats shifted their flight towards faster (+10 to +44%) and straighter trajectories (+33%) with lower probability of prey capture attempts (−18 to −39%) at solar farms.Since these changes in flight features are explicit indicators of a decrease in bat feeding behaviour, the implementation of ground‐mounted solar farms is likely to result in reduced feeding habitat quality for bats.Synthesis and applications: The negative effects of solar farms on bat flight and feeding behaviour should be considered when solar energy projects are planned. Research is needed to understand the mechanisms underlying the effects; for example, shading underneath solar panels may reduce plant biomass and therefore insect prey availability. Until exact mechanisms are identified, efforts should be made, first to avoid building solar farms on sites with great feeding potential for bats, and second to offset residual effects by improving the surrounding land and/or solar farms to provide better foraging opportunities. In this way, populations of bats can be supported alongside the generation of renewable energy. [ABSTRACT FROM AUTHOR]

Passive acoustic methods are increasingly used in biodiversity research and monitoring programs because they are cost-effective and permit the collection of large datasets. However, the accuracy of the results depends on the bioacoustic characteristics of the focal taxa and their habitat use. In particular, this applies to bats which exhibit distinct activity patterns in three-dimensionally structured habitats such as forests. We assessed the performance of 21 acoustic sampling schemes with three temporal sampling patterns and seven sampling designs. Acoustic sampling was performed in 32 forest plots, each containing three microhabitats: forest ground, canopy, and forest gap. We compared bat activity, species richness, and sampling effort using species accumulation curves fitted with the clench equation. In addition, we estimated the sampling costs to undertake the best sampling schemes. We recorded a total of 145,433 echolocation call sequences of 16 bat species. Our results indicated that to generate the best outcome, it was necessary to sample all three microhabitats of a given forest location simultaneously throughout the entire night. Sampling only the forest gaps and the forest ground simultaneously was the second best choice and proved to be a viable alternative when the number of available detectors is limited. When assessing bat species richness at the 1-km2 scale, the implementation of these sampling schemes at three to four forest locations yielded highest labor cost-benefit ratios but increasing equipment costs. Our study illustrates that multiple passive acoustic sampling schemes require testing based on the target taxa and habitat complexity and should be performed with reference to cost-benefit ratios. Choosing a standardized and replicated sampling scheme is particularly important to optimize the level of precision in inventories, especially when rare or elusive species are expected. [ABSTRACT FROM AUTHOR]

Voigt et al. (2021) provide a thorough analysis of the restrictions inherent to the estimation of bat abundance from acoustic surveys, and conclude that limitations of acoustic monitoring impede the reliable evaluation of bat fatalities at wind turbines. We argue that acoustic data recorded at the nacelle of wind turbines have been experimentally validated as a useful and appropriate measure of bat collisions. Therefore, acoustic data can be used to estimate bat fatalities at wind turbines, provided a referenced and standardised protocol for data acquisition and analysis is used. [ABSTRACT FROM AUTHOR]

Scientists have warned decision‐makers about the severe consequences of the global environmental crisis since the 1970s. Yet ecological degradation continues and little has been done to address climate change. We investigated early‐career conservation researchers' (ECR) perspectives on, and prioritization of, actions furthering sustainability. We conducted a survey (n = 67) and an interactive workshop (n = 35) for ECR attendees of the 5th European Congress of Conservation Biology (2018). Building on these data and discussions, we identified ongoing and forthcoming advances in conservation science. These include increased transdisciplinarity, science communication, advocacy in conservation, and adoption of a transformation‐oriented social–ecological systems approach to research. The respondents and participants had diverse perspectives on how to achieve sustainability. Reformist actions were emphasized as paving the way for more radical changes in the economic system and societal values linked to the environment and inequality. Our findings suggest that achieving sustainability requires a strategy that (1) incorporates the multiplicity of people's views, (2) places a greater value on nature, and (3) encourages systemic transformation across political, social, educational, and economic realms on multiple levels. We introduce a framework for ECRs to inspire their research and practice within conservation science to achieve real change in protecting biological diversity. [ABSTRACT FROM AUTHOR]