Balancing renewable energy and biodiversity: Assessing solar farm effects on bat activity

The Mangrove forests underpin coastal resilience, biodiversity, and livelihoods across Papua New Guinea, yet conventional monitoring in the Kamiali Wildlife Management Area (KWMA) remains sporadic and invasive. This study synthesizes evidence from a PRISMA-guided systematic literature review and evaluates a suite of complementary technologies—UAV-based multispectral/hyperspectral and LiDAR sensing, SAR and optical satellites, environmental DNA (eDNA) metabarcoding, passive acoustic monitoring (PAM), UAV thermal imaging, and uncrewed surface vessels (USVs)—to propose a hybrid monitoring framework tailored to the biophysical and social conditions of the KWMA. Across recent sources, we assess detection capacities, spatiotemporal coverage, cost efficiency, and operational feasibility under crocodile-inhabited tidal channels, dense canopies, and limited access, and we integrate outputs with global mangrove watch classifications and community priorities to inform conservation decisions and climate adaptation. The findings indicate that UAV LiDAR and hyperspectral imaging resolve canopy structure, height, and dieback at plot scales; SAR plus optical imagery enables wall-to-wall change detection across tidal regimes; eDNA reveals cryptic and rare taxa while reducing field disturbance; PAM and thermal imaging track the seasonal activity of birds, bats, and other fauna; and USVs extend water quality and geomorphological observations along hazardous channels. A cost comparison revealed that mixed sensor stacks outperform single-method approaches in terms of accuracy, repeatability, and safety when paired with streamlined field protocols. To ensure equitable practice, the framework embeds free, prior, and informed consent; data sovereignty; and coproduction with local stewards, coupled with training pathways via UN volunteers. We outline stepwise protocols for sensor selection, sampling design, QA/QC, and data fusion, culminating in decision-ready indicators aligned with reporting and sustainable development goals. The resulting roadmap is pilot-ready for KWMA and transferable to similar Pacific contexts, strengthening evidence-based governance while building local capacity. This study demonstrates how combining aerial, satellite, molecular, acoustic, thermal, and surface-vessel observations can deliver rigorous, cost-aware mangrove monitoring that advances biodiversity conservation, climate resilience, and community well-being.

Spatial proximity to farmland enhances bat richness and activity in planted forests

Mitigating light pollution through motion-controlled LED lighting to protect bats.

Both composition and configuration of forests and urban development shape bat activity and diversity in North American temperate forests

Abstract Hedgerows are key semi‐natural elements in European agricultural landscapes supporting diverse wildlife, including bats, that depend on these linear elements for foraging and commuting. Despite replanting initiatives, many hedgerows remain degraded due to intensive management practices such as overtrimming. To develop effective and generalisable conservation guidelines, more research is needed to understand how both management practices and intrinsic hedgerow characteristics influence bat species with different foraging strategies. We conducted passive acoustic monitoring across 448 hedgerows to assess the influence of six characteristics on bat activity: trimming method, height, width, foliage density, connectivity and woody plant diversity. We examined responses for two species associated with hedgerow landscapes ( Barbastella barbastellus , Rhinolophus ferrumequinum ) and three echolocation guilds: short‐, mid‐ and long‐range echolocators (SRE, MRE, LRE), corresponding to clutter, edge and open‐space foragers, respectively. Pollarding consistently increased bat activity, especially for tree‐dwelling species, likely by maintaining mature trees with larger crowns and diversified microhabitats. Coppicing generally reduced activity for SRE, B. barbastellus and R. ferrumequinum , while increasing LRE activity. Taller, tree‐filled hedgerows generally supported higher bat activity, whereas width and foliage density had more limited effects. Finally, uninterrupted hedgerow segments enhanced SRE and MRE activity, highlighting the importance of local habitat continuity in creating effective corridors for bat movement. Woody plant diversity was also positively associated with SRE activity. These results were mostly consistent across simplified open croplands and structurally complex bocage landscapes. Synthesis and applications . Our findings underscore the value of extensive hedgerow management in promoting on‐farm bat activity and support the integration of simple hedgerow quality assessment protocols into agri‐environment schemes. Consistent with previous research, we confirm the importance of tall, tree‐filled hedgerows and emphasise the need to preserve mature trees. We also provide novel insights: hedgerow continuity and low‐intensity trimming methods can further improve habitat suitability, particularly for tree‐dwelling bats. Our management recommendations align with evidence from other taxonomic groups, including birds and invertebrates, and can contribute to broader biodiversity conservation strategies.

Association between bat-predator species richness and Nipah virus spillover risk in Bangladesh

Bat activity at ecovoltaic solar energy developments in the Midwestern United States

Tree and landscape characteristics outweigh insect abundance in driving bat activity in West African rice fields

Forest proximity enhances bat activity in Midwestern agricultural fields: Implications for edge management and ecosystem services

South Mediterranean forests are known for their spatial and temporal variability in fauna and flora species abundance. Using acoustic surveys and generalized linear models, we investigated the nocturnal activity of bats in five forest sites in northeast Algeria from March to November. A total of 12 species were detected: Rhinolophus blasii, R. hipposideros, Tadarida teniotis, Miniopterus schreibersii, Eptesicus isabellinus, Hypsugo savii, Pipistrellus kuhlii, P. pipistrellus, Plecotus gaisleri, Myotis cappaccinii, M. emarginatus, and M. punicus. Activity levels varied significantly among months and sites. Overall bat activity and P. kuhlii activity increased from spring to summer, peaked in August, and slightly decreased in early autumn. Activity levels also differed markedly among forest sites, with low activity levels in the urban forest site, and E. isabellinus was mostly active in only two forest sites. These results suggest that both environmental conditions and location-specific factors shape the activity patterns.

Disclosure: A.D. De Jesus: None. A. Karagiannidis: None. P. Sridhar: None. M.A. Cowley: None. T. Mustafa: None. B.A. Henry: None.Introduction: It is estimated that Worldwide, over 200 million women use a hormonal contraceptive, yet few studies have addressed possible side-effects on energy balance and glucose metabolism. To date, the role of 17β-estradiol on energy balance has been well-documented; however, the role of progesterone or synthetic progestins is largely unknown. The aim of the study was to investigate the effects of different hormonal contraceptives on energy expenditure and glucose metabolism in healthy young women. Furthermore, we aimed to address whether the dose or pharmacological profile of progestin influenced the metabolic effects of hormonal contraceptives. Methods: Young female participants (ages 18-39y/o; n=9-12), who were eumenorrheic (luteal phase of the menstrual cycle) or taking hormonal contraceptives, including either combined oral contraceptive pill (COCP) or progestin-only implant were recruited. Women using COCP were subdivided into two groups: low dose (progestin concentration of 100-150μg/ day) or high dose (progestin concentrations of 2-3mg/ day). Resting energy expenditure (REE) was determined using the indirect calorimetry in fasted conditions. Body composition (BMI, weight, waist circumference) was assessed. Cutaneous supraclavicular (SCV) temperatures in response to a mild cold exposure (15oC) or an oral glucose tolerance test (75g) were assessed using infrared thermography. Continuous glucose monitors determined changes in transcutaneous glucose concentrations over time. A single blood sample was collected to measure 17β-estradiol, progesterone, follicle stimulating hormone (FSH), and insulin concentrations. Results: Concentrations of 17β-estradiol and progesterone were negligible in women using high dose COCPs (p<0.0001). In addition, FSH levels were lower in the high dose COCP group compared to control (p<0.05) and progestin-only groups (p<0.0001). Overall, cold-induced adaptive thermogenesis was shown to be lower with contraceptive use (p<0.0001). The inhibitory effect on BAT heat production was greatest in the high dose COCP (p<0.0001) and progestin-only groups (p<0.0001). In response to the glucose challenge, BAT activity was reduced with contraceptive use (p<0.01). Similarly, the inhibitory effect on BAT temperature was greatest in the high dose COCP group (p<0.0001). Moreover, the reduction in BAT temperature was associated with increased glucose concentrations and impaired glucose tolerance in the high dose COCP group (p<0.01). Insulin levels were similar in all groups. There was no effect of low dose COCPs on BAT activation in response to cold or glucose. Conclusion: Hormonal contraceptives that contain high dose progestin inhibited BAT activation and caused glucose intolerance in young women. These results support the use of low dose COCPs particularly in women who are at risk of developing cardiometabolic disease.Presentation: Monday, July 14, 2025

Bats have unique reproductive strategies that are closely related to testicular metabolic adaptations, such as prolonged sperm storage. This study examined the expression of glucose transporter 5 (GLUT-5), a fructose-specific member of the facilitative glucose transporter family, in the testes of roundleaf bats (Hipposideros spp.) collected from various locations in Thailand during their active reproductive season (July to September) and explored its association with biometric traits. To assess GLUT-5's localization and expression levels, testicular tissues from 50 adult males representing Hipposideros larvatus, Hipposideros armiger, and Hipposideros lekaguli species were analyzed using immunohistochemistry and Western blotting. Strong GLUT-5 immunoreactivity was observed in the cytoplasm of spermatocytes, spermatids, and spermatozoa, while weak staining was seen in spermatogonia. No GLUT-5 expression was detected in Leydig or Sertoli cells. Staining intensity varied significantly by month, with the highest levels observed in August (p < 0.05), exceeding those in July and September. Western blotting identified two GLUT-5 isoforms (55 and 100 kDa), with relative intensities that changed across the reproductive timeline. In parallel, morphometric analysis revealed that the height of the germinal epithelium and the diameter of the seminiferous tubules were significantly greater in July than in August and September, reflecting peak spermatogenic activity. These findings suggest that the seasonal regulation of fructose transport, along with changes in testicular architecture, may support testicular function and sperm maturation. The differential expression of GLUT-5 isoforms may reflect their distinct roles in body growth, reproductive maturation, and seasonal testicular activity in Hipposiderid bats.

Leptin is known to enhance BAT activity through sympathetic stimulation. However, in vitro studies suggest leptin could also act directly on adipocytes to promote lipolysis. Whether these peripheral effects of leptin are relevant to systemic metabolic control, in obesity, remain ill-defined. We addressed this question by selectively restoring leptin receptor (LEPR) in adipocytes of obese LEPR conditional KO mice. LEPR restoration selectively enhanced BAT activity in male mice, which led to improved glycemic control and cardiovascular function. These findings revealed a crucial role for BAT leptin signaling in regulating energy expenditure, glycemic and cardiovascular health, primarily in males.

Research Highlight: Moser, V., Capitani, L., Zehnder, L., Hürbin, A., Obrist, M., Ecker, K., Boch, S., Minnig, S., Angst, C., Pomati, F., & Risch, A. (2025). Habitat heterogeneity and food availability in beaver-engineered streams foster bat richness, activity and feeding. Journal of Animal Ecology. https://doi.org/10.1111/1365-2656.70136. Ecosystem engineers increase habitat heterogeneity, altering abiotic and biotic resources and are key to effective nature recovery. Reintroductions of Eurasian beavers (Castor fiber) in Europe have indirectly benefitted multiple taxonomic groups, aquatic and terrestrial, as their activities result in wetland restoration and diversification of vegetation composition and structure. Bats have been found to be positively impacted by beaver activity, yet the causal drivers were unknown. In a recent study, Moser etal. (2025) monitored bat species richness, activity and foraging activity at beaver pools and control beaver-free sites in Switzerland, finding significant increases in all three measures. Importantly, this study is the first to show significant positive impacts on bat foraging at beaver-engineered sites, and increases in species richness included red-listed species of conservation concern. By testing causal links of the impact of direct (increased canopy heterogeneity and standing deadwood density) and indirect (increased arthropod prey abundance) impacts of beaver engineering on bats, the authors found mixed responses at the foraging guild level. Edge-hunting aerial hawkers benefitted most from beaver engineering, and increased standing deadwood density was shown to have the strongest impact on bats. This study provides key evidence for the positive outcomes of beaver reintroductions on local biodiversity, highlighting the value of ecosystem engineers for nature recovery strategies.

Abstract The impact on wildlife of large‐scale outdoor music events held in urban green spaces remains poorly understood. Bats are a taxon of focus for evening events, because of their protected status, nocturnality, sensitivity to artificial lighting, and reliance on sound for navigation and foraging. While experimental field studies have singly demonstrated the effects of artificial night‐time lighting and noise on bat activity, studies made during actual music events, associated with unusually high levels of both artificial lighting and noise, are lacking. In this study, we deployed passive acoustic detectors within an urban parkland to monitor bat activity over a 23‐night period, during which two large weekend concert events were held. Nine bat species were recorded. Activity minutes were calculated for all bats and some species groups, and the effect of concerts, alongside several abiotic variables, were measured. Total bat activity was not depressed on concert nights, but total bat activity was reduced during concert hours compared with the same times on nights without concerts. This was significant at the species level for Pipistrellus pipistrellus and Myotis species, with the latter also showing a marginally significant delay in peak activity on concert nights. We suggest that the reduction and delay in bat activity observed during concerts may impair bat foraging success with potential implications for fitness. Solutions. We propose practical solutions to reduce these risks, such as a better‐informed placement and timing of urban outdoor concerts away from important bat habitats and outside the breeding season.

ABSTRACTSky islands, ecosystems found on geographically isolated mountain peaks, are among the most biodiverse ecosystems in the world but face a disproportionately high threat from climate change. High‐elevation, montane ecosystems, which are already at their upper altitudinal limits, are predicted to severely contract in response to climate change. The identification and conservation of refugia is an increasingly important approach for protecting biodiversity associated with imperiled ecosystems. We explored the spruce‐fir–northern hardwood ecotone as a possible refugium for mammals in the Southern Appalachian red spruce (Picea rubens)‐Fraser fir (Abies fraseri) sky islands. We conducted livetrapping, camera trapping, and ultrasonic acoustic surveys to characterize mammal diversity across the spruce‐fir–northern hardwood forest gradient on Grandfather Mountain and Roan Mountain Highlands in western North Carolina, USA. We detected four out of the five spruce‐fir‐associated small mammal species in both spruce‐fir and ecotone habitats. Mammal species richness, alpha diversity, and bat activity tended to be higher in the ecotone than in the other forest types on both mountains. Next, the abundance of small mammals associated with spruce‐fir was higher in the spruce‐fir and ecotone forests for one of the three species we were able to estimate. Together, our results suggest that the spruce‐fir–northern hardwood ecotone might serve as refugium for mammal species that are associated with spruce‐fir sky islands in the Southern Appalachian Mountains and mammalian conservation efforts in this biodiversity hotspot should consider focusing on the ecotone in addition to the adjacent spruce‐fir ecosystem.

Warming winters disrupt bat activity and hibernation in mediterranean olive agroecosystems

Abstract Bat populations are declining globally. Maintaining high‐quality habitat for bats can help mitigate extinction risk. Natural and semi‐natural linear vegetation features have been shown to provide shelter and foraging habitat for bats in temperate agroecosystems in Europe, yet their value for bats in North America has received little attention. Using automated ultrasonic recorders, we assessed bat species richness and activity across agricultural drainage ditches that varied in mean vegetation height, variability in vegetation height, and mean width in agroecosystems in eastern Ontario, Canada. Landscapes surrounding recording sites also varied in forest amount and mean field size, and recording sites were located at different distances from the nearest forest patch. We found that in general, bat activity at the community level and at the individual species level was positively associated with mean vegetation height and mean vegetation width; however, species appeared to vary in their response to variation in vegetation height. We also found a general positive relationship within and across species for bat activity with forest amount at the landscape scale. Overall, our results suggest maintaining or increasing vegetation height along drainage ditches and field margins as well as maintaining or increasing forest amount at the landscape scale will best support bats in temperate North American agroecosystems.

Abstract Passive acoustic monitoring of bats is used in a growing number of studies in applied and basic research, from local to global scales. Despite the publication of good‐practice recommendations, several unsettled debates persist about the possibilities and limits offered by passive acoustic monitoring of bats. In this paper, we summarise and discuss these debates and invite the research community to invest efforts in resolving them. These debates include the correlation between acoustic bat counts and the actual number of individuals, the influence of weather and bat behaviour on acoustic detectability, the impact of prey size on bat activity counts and the influence of biogeography on bat call characteristics. We also shed light on promising metrics and models which, in spite of their potential, are not broadly used by ecologists and researchers. Indeed, some alternative acoustic metrics can be easily measured to quantify and qualify bat foraging activity, and several models have been developed to assess bat population sizes using passive acoustic monitoring. Such models and metrics have the potential to revolutionise how we interpret the results of passive acoustic monitoring. We strongly recommend that the community of bat researchers and practitioners progress in standardising the protocols for spatiotemporal analyses on large scales, such as estimating population trends and building species distribution models. We also insist on the importance of archiving and sharing data to make raw sound recordings available for re‐analysis, to adapt to the evolution of the technology, the metrics developed and the taxonomy.