Pond characteristics as determinants of species diversity and community composition in desert bats

Although water availability is known to affect landscape-scale patterns of wildlife diversity and distribution in arid environments, little is known about the microhabitat characteristics that shape the local-scale distribution of desert bats. We examined the relative importance of pond microhabitat characteristics for the conservation of bats, and hypothesized that in arid environments, patterns of bat diversity and community composition relate to the size of the pond and its hydroperiod (the number of months a pond holds water), a term we use to distinguish between permanent, semi-permanent and temporary ponds. We combined acoustic monitoring with video recording and an experimental approach to study bat activity over natural ponds in the Negev Desert, Israel. We found that both within and between ponds bat species richness and activity significantly increased with pond size. An experimental reduction of pond size led to a significant reduction in bat species richness and activity and affected the bat community composition. In contrast to pond size, pond hydroperiod did not affect bat diversity, as temporary ponds had equivalent levels of bat species richness and activity to permanent ponds. However, hydroperiod did couple with pond size to affect the bat community composition, whereby non-desert bat species that have a higher frequency of drinking were associated with larger and more permanent ponds. Our results highlight the importance of larger temporary ponds (ponds over 15 m in length and 0.5 m in depth) for the conservation of biodiversity in arid environments

Does interspecific competition drive patterns of habitat use in desert bat communities?

Bodies of water are a key foraging habitat for insectivorous bats. Since water is a scarce and limiting resource in arid environments, bodies of open water may have a structuring effect on desert bat communities, resulting in temporal or spatial partitioning of bat activity. Using acoustic monitoring, we studied the spatial and temporal activity patterns of insectivorous bats over desert ponds, and hypothesised that sympatric bat species partition the foraging space above ponds based on interspecific competitive interactions. We used indirect measures of competition (niche overlap and competition coefficients from the regression method) and tested for differences in pond habitat selection and peak activity time over ponds. We examined the effect of changes in the activity of bat species on their potential competitors. We found that interspecific competition affects bat community structure and activity patterns. Competing species partitioned their use of ponds spatially, whereby each species was associated with different pond size and hydroperiod (the number of months a pond holds water) categories, as well as temporally, whereby their activity peaked at different hours of the night. The drying out of temporary ponds increased temporal partitioning over permanent ponds. Differences in the activity of species over ponds in response to the presence or absence of their competitors lend further support to the role of interspecific competition in structuring desert bat communities. We suggest that habitat use and night activity pattern of insectivorous bats in arid environments reflect the trade-offs between selection of preferred pond type or activity time and constraints posed by competitive interactions

Predicting the effect of interspecific competition on habitat suitability for the endangered african wild dog under future climate and land cover changes

Apex predators play an important role in regulating ecological interactions, and therefore their loss can affect biodiversity across trophic levels. Large carnivores have experienced substantial population and range declines across Africa, and future climate change is likely to amplify these threats. Hence it is important to understand how future environmental changes will affect their long-term habitat suitability and population persistence. This study aims to identify the factors limiting the distribution of the endangered African wild dog,Lycaon pictus,and determine how biotic interactions and changing climate and land cover will affect future range suitability. We use Species Distribution Models (SDMs) to predict the current and future distribution of suitable conditions forL. pictusand its dominant competitorPanthera leo. We show that range suitability forL. pictusis limited by climatic and land cover variables, as well as high niche and range overlap withP. leo. Although both species are predicted to experience range contractions under future climate change,L. pictusmay benefit from release from the effect of interspecific competition in eastern and central parts of its range. Our study highlights the importance of including land cover variables with corresponding future projections and incorporating the effects of competing species when predicting the future distribution of species whose ranges are not solely limited by climate. We conclude that SDMs can help identify priority areas for the long-term conservation of large carnivores, and therefore should be used to inform adaptive conservation management in face of future climate change

Unravelling the evolutionary history and future prospects of endemic species restricted to former glacial refugia

The contemporary distribution and genetic composition of biodiversity bear a signature of species’ evolutionary histories and the effects of past climatic oscillations. For many European species, the Mediterranean peninsulas of Iberia, Italy and the Balkans acted as glacial refugia and the source of range recolonization, and as a result, they contain disproportionately high levels of diversity. As these areas are particularly threatened by future climate change, it is important to understand how past climatic changes affected their biodiversity. We use an integrated approach, combining markers with different evolutionary rates and combining phylogenetic analysis with approximate Bayesian computation and species distribution modelling across temporal scales. We relate phylogeographic processes to patterns of genetic variation in Myotis escalerai, a bat species endemic to the Iberian Peninsula. We found a distinct population structure at the mitochondrial level with a strong geographic signature, indicating lineage divergence into separate glacial refugia within the Iberian refugium. However, microsatellite markers suggest higher levels of gene flow resulting in more limited structure at recent time frames. The evolutionary history of M. escalerai was shaped by the effects of climatic oscillations and changes in forest cover and composition, while its future is threatened by climatically induced range contractions and the role of ecological barriers due to competition interactions in restricting its distribution. This study warns that Mediterranean peninsulas, which provided refuge for European biodiversity during past glaciation events, may become a trap for limited dispersal and ecologically limited endemic species under future climate change, resulting in loss of entire lineages

Painting maps with bats: Species distribution modelling in bat research and conservation

Species distribution models (SDMs) offer an effective tool for identifying species conservation requirements and forecasting how global environmental changes will affect species diversity and distribution. This approach is particularly relevant for bats because their nocturnal behaviour hinders detectability and identification in flight. Despite their important contribution to global biodiversity and wide geographical ranges, bats have been under-represented in early SDM studies, and only in the last few years has this approach become more widely used in bat research. We carried out a meta-analysis of the published literature to review the history of the use of SDMs in bat research and their application in conservation, climate change assessments and genetic studies. We focus on the geographical coverage, theme and modelling algorithm of published studies, and compare studies that are uniquely dedicated to bats to multi-taxa studies that include bats. We provide recommendations for good modelling practices through considering spatial scale and spatial biases, selecting ecologically relevant variables, following rigorous modelling protocols, and recognising the limitations of extrapolation across temporal scales. We suggest future developments that will further favour the use of SDMs to study bat ecology and biogeography, as well as inform conservation management. We conclude that despite an increase in bat SDM studies, their scope and application can be further enhanced through incorporating dispersal, landscape connectivity and biotic interactions between bats, their prey and their pathogens

Predicting the effect of interspecific competition on habitat suitability for the endangered African wild dog under future climate and land cover changes

Apex predators play an important role in regulating ecological interactions, and therefore their loss can affect biodiversity across trophic levels. Large carnivores have experienced substantial population and range declines across Africa, and future climate change is likely to amplify these threats. Hence it is important to understand how future environmental changes will affect their long-term habitat suitability and population persistence. This study aims to identify the factors limiting the distribution of the endangered African wild dog, Lycaon pictus, and determine how biotic interactions and changing climate and land cover will affect future range suitability. We use Species Distribution Models (SDMs) to predict the current and future distribution of suitable conditions for L. pictus and its dominant competitor Panthera leo. We show that range suitability for L. pictus is limited by climatic and land cover variables, as well as high niche and range overlap with P. leo. Although both species are predicted to experience range contractions under future climate change, L. pictus may benefit from release from the effect of interspecific competition in eastern and central parts of its range. Our study highlights the importance of including land cover variables with corresponding future projections and incorporating the effects of competing species when predicting the future distribution of species whose ranges are not solely limited by climate. We conclude that SDMs can help identify priority areas for the long-term conservation of large carnivores, and therefore should be used to inform adaptive conservation management in face of future climate change

Insectivorous bats in Indian rice fields respond to moonlight, temperature, and insect activity

ABSTRACT: Context - Rice, India’s most widely grown crop, suffers substantial and increasing yield loss to insect pests. Insectivorous bats are known suppressors of insect pests, providing significant economic value to agricultural systems worldwide, yet their ecology in Indian agricultural landscapes is poorly understood. Objectives - We assess the influence of key biotic and abiotic factors on the activity of insectivorous bats over the growing season and within a night in a rice cultivation landscape. Methods - Passive acoustic recorders were used to track bat activity in a rice field in the Sonitpur district of Assam, India. We used generalised linear mixed models to analyse the effect of temperature, insect activity, and moonlight intensity on the activity of six bat sonotypes. We also used a multimodal analysis to describe the within-night activity patterns of these sonotypes. Results - Minimum nightly temperature and moonlight intensity had a positive and negative influence, respectively, on the activity of six bat sonotypes, while the activity of four bat sonotypes increased with insect activity. Within-night activity showed one of two patterns: three sonotypes displayed a dusk peak in activity, while the three other sonotypes were active through the night. Conclusion - The potential to maximise natural pest control in agricultural landscapes can only be realised through understanding the ecology of natural enemies in these landscapes. Our findings suggest that bats in rice fields are tracking insects over a season and within a night, pointing to a valuable ecosystem service in Indian agriculture that is yet to be quantified.info:eu-repo/semantics/publishedVersio

Landscape features drive insectivorous bat activity in Indian rice fields

Context Insectivorous bats have been shown to control a number of agricultural insect pests. As bats exhibit species-specific responses to the surrounding landscape, tied closely to their morphology and foraging mode, the activity and distribution patterns of bats, and consequently the ecosystem services they provide, are influenced by the landscape characteristics. Objectives This study aims to determine which features in the landscape surrounding rice fields influence the activity levels of insectivorous bats, and at what scales they are most influential. Methods We collected acoustic recordings to determine activity levels of seven bat sonotypes in rice fields surrounded by a variety of land-cover types in the Nagaon district of Assam, India. Using this, we determined the most important set of features in the surrounding landscape, and the scales at which had the strongest impact, for each sonotype. Results Our results suggest that tree cover variables are the most important predictors of bat activity in rice fields. Distance to nearest forest, area of forest within 1 km, distance to nearest forest edge, and landscape heterogeneity influenced all five of the analysed bat sonotypes. Also important were the amount of urban land within 1 km, which exerted a negative effect on the activity of one sonotype, and moonlight activity, which negatively influenced the activity levels of one sonotype. Conclusion Our results demonstrate that when flying over rice fields, bat activity is most influenced by presence and proximity of trees. Therefore, increasing tree cover in agricultural landscapes will increase bat activity and likely the level of pest control

Emerging zoonotic diseases originating in mammals: a systematic review of effects of anthropogenic land-use change

This is the final version. Available on open access from Wiley via the DOI in this record1. Zoonotic pathogens and parasites transmitted from vertebrates to humans are a major public health risk with high associated global economic costs. The spread of these diseases accelerates with anthropogenic land-use changes (LUC), like deforestation, urbanisation and agriculture, factors that are expected to increase in the future due to human population expansion and increasing demands for resources. 2. We systematically review the literature on anthropogenic LUC and zoonotic diseases, highlighting the most prominent mammalian reservoirs and pathogens, analysing trends in publications and identifying avenues for future research. 3. The number of publications increased over the past three decades. The majority of studies were global reviews that did not focus on specific taxa. South America and Asia were the most studied regions. The most studied mammalian taxa were rodents, livestock and carnivores, while the most studied LUC was urbanisation. Associations were identified between hosts and type of LUC, and hosts and pathogens. 4. Research into specific animal reservoirs has improved our understanding of how zoonotic diseases spread with LUC. Host behaviour can be altered when their habitats are changed, which in turn impacts the pathogens they carry and the probability of disease spread to humans. Understanding this has enabled the identification of factors that would alter the risk of emergence, like virulence, pathogen diversity or ease of transmission, and the pathogens most likely to emerge, though many pathogens have not been studied yet. 5. Predicting how zoonotic diseases emerge and spread in response to anthropogenic LUC requires more empirical and data synthesis studies that link host ecology and responses to LUC with pathogen ecology and disease spread. The link between anthropogenic impacts on the natural environment and the recent COVID-19 outbreak highlights the urgent need to understand how anthropogenic LUC affects the risk of spillover and spread of mammalian zoonotic diseasesNatural Environment Research Council (NERC

Beyond species distribution modelling: A landscape genetics approach to investigating range shifts under future climate change

Understanding how biodiversity will respond to future climate change is a major conservation and societal challenge. Climate change is predicted to force many species to shift their ranges in pursuit of suitable conditions. This study aims to use landscape genetics, the study of the effects of environmental heterogeneity on the spatial distribution of genetic variation, as a predictive tool to assess how species will shift their ranges to track climatic changes and inform conservation measures that will facilitate movement. The approach is based on three steps: 1) using Species Distribution Models (SDMs) to predict suitable ranges under future climate change, 2) using the landscape genetics framework to identify landscape variables that impede or facilitate movement, and 3) extrapolating the effect of landscape connectivity on range shifts in response to future climate change. I show how this approach can be implemented using the publicly available genetic dataset of the grey long-eared bat,Plecotus austriacus, in the Iberian Peninsula. Forest cover gradient was the main landscape variable affecting genetic connectivity between colonies. Forest availability is likely to limit future range shifts in response to climate change, primarily over the central plateau, but important range shift pathways have been identified along the eastern and western coasts. I provide outputs that can be directly used by conservation managers and review the viability of the approach. Using landscape genetics as a predictive tool in combination with SDMs enables the identification of potential pathways, whose loss can affect the ability of species to shift their range into future climatically suitable areas, and the appropriate conservation management measures to increase landscape connectivity and facilitate movement