Toward solving the global green-green dilemma between wind energy production and bat conservation.

Wind energy production is growing rapidly worldwide in an effort to reduce greenhouse gas emissions. However, wind energy production is not environmentally neutral. Negative impacts on volant animals, such as bats, include fatalities at turbines and habitat loss due to land-use change and displacement. Siting turbines away from ecologically sensitive areas and implementing measures to reduce fatalities are critical to protecting bat populations. Restricting turbine operations during periods of high bat activity is the most effective form of mitigation currently available to reduce fatalities. Compensating for habitat loss and offsetting mortality are not often practiced, because meaningful offsets are lacking. Legal frameworks to prevent or mitigate the negative impacts of wind energy on bats are absent in most countries, especially in emerging markets. Therefore, governments and lending institutions are key in reconciling wind energy production with biodiversity goals by requiring sufficient environmental standards for wind energy projects.

Exploring the potential for online data sources to enhance species threat mapping through the case study of global bat exploitation.

Expanding digital data sources, including social media and online news, provide a low-cost way to examine human-nature interactions, such as wildlife exploitation. However, the extent to which using such data sources can expand or bias understanding of the distribution and intensity of threats has not been comprehensively assessed. To address this gap, we quantified the geographical and temporal distribution of online sources documenting the hunting and trapping, consumption, or trade of bats (Chiroptera) and compared these with the distribution of studies obtained from a systematic literature search and species listed as threatened by exploitation on the International Union for Conservation of Nature Red List. Online records were collected using automated searches of Facebook, Twitter, Google, and Bing and were filtered using machine classification. This yielded 953 relevant social media posts and web pages, encompassing 1099 unique records of bat exploitation from 84 countries. Although the number of records per country was significantly predicted by the number of academic studies per country, online records provided additional locations and more recent records of bat exploitation, including 22 countries not present in academic literature. This demonstrates the value of online resources in providing more complete geographical representation. However, confounding variables can bias the analysis of spatiotemporal trends. Online bat exploitation records showed peaks in 2020 and 2014, after accounting for increases in internet users through time. The second of these peaks could be attributed to the COVID-19 outbreak, and speculation about the role of bats in its epidemiology, rather than to true changes in exploitation. Overall, our results showed that data from online sources provide additional knowledge on the global extent of wildlife exploitation, which could be used to identify early warnings of emerging threats and pinpoint locations for further research.

Sondeo del potencial de las fuentes virtuales de datos para mejorar el mapeo de amenazas para las especies por medio del estudio de caso de la explotación mundial de murciélagos Resumen La expansión de las fuentes virtuales, incluidas las redes sociales y las noticias en línea, proporciona una forma asequible de analizar las interacciones entre el humano y la naturaleza, como la explotación de fauna. Sin embargo, no se ha analizado por completo el rango al que dichas fuentes pueden expandir o sesgar el conocimiento de la distribución e intensidad de las amenazas. Para abordar este vacío cuantificamos la distribución geográfica y temporal de las fuentes virtuales que documentan la caza, captura, consumo o mercado de murciélagos (Chiroptera) y las comparamos con la distribución de los estudios obtenidos de una búsqueda sistemática en la literatura y con las especies catalogadas como amenazadas por la explotación según la Lista Roja de la Unión Internacional para la Conservación de la Naturaleza. Recolectamos los registros virtuales por medio de búsquedas automatizadas en Facebook, Twitter, Google y Bing y después las filtramos con clasificaciones automatizadas. Esto arrojó 953 publicaciones relevantes en redes sociales y sitios web que englobaban 1099 registros únicos de la explotación de murciélagos en 84 países. Aunque pronosticamos de forma significativa el número de registros por país con el número de estudios académicos por país, los registros virtuales proporcionaron localidades adicionales y registros más recientes de la explotación de murciélagos, incluyendo a 22 países que no se encuentran en la literatura académica. Lo anterior demuestra el valor que tienen los recursos en línea para proporcionar una representación geográfica más completa. Sin embargo, las variables confusas pueden sesgar el análisis de las tendencias espaciotemporales. Los registros virtuales de la explotación de murciélagos mostraron picos en 2020 y en 2014, esto después de considerar el incremento de usuarios de internet con el tiempo. El segundo pico podría atribuirse al brote de COVID­19 y la especulación en torno al papel que tenían los murciélagos en su epidemiología y no tanto a un verdadero cambio en la explotación. En general, nuestros resultados mostraron que los datos de las fuentes virtuales proporcionan conocimiento adicional sobre el alcance mundial de la explotación de fauna, el cual podría usarse para identificar señales tempranas de amenazas emergentes y ubicar localidades para su mayor investigación.

Bat Motion can be Described by Leap Frogging.

We present models of bat motion derived from radio-tracking data collected over 14 nights. The data presents an initial dispersal period and a return to roost period. Although a simple diffusion model fits the initial dispersal motion we show that simple convection cannot provide a description of the bats returning to their roost. By extending our model to include non-autonomous parameters, or a leap frogging form of motion, where bats on the exterior move back first, we find we are able to accurately capture the bat's motion. We discuss ways of distinguishing between the two movement descriptions and, finally, consider how the different motion descriptions would impact a bat's hunting strategy.

Lack of detection of SARS-CoV-2 in British wildlife 2020-21 and first description of a stoat (Mustela erminea) Minacovirus.

Repeat spillover of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) into new hosts has highlighted the critical role of cross-species transmission of coronaviruses and establishment of new reservoirs of virus in pandemic and epizootic spread of coronaviruses. Species particularly susceptible to SARS-CoV-2 spillover include Mustelidae (mink, ferrets and related animals), cricetid rodents (hamsters and related animals), felids (domestic cats and related animals) and white-tailed deer. These predispositions led us to screen British wildlife with sarbecovirus-specific quantitative PCR and pan coronavirus PCR assays for SARS-CoV-2 using samples collected during the human pandemic to establish if widespread spillover was occurring. Fourteen wildlife species (n=402) were tested, including: two red foxes (Vulpes vulpes), 101 badgers (Meles meles), two wild American mink (Neogale vison), 41 pine marten (Martes martes), two weasels (Mustela nivalis), seven stoats (Mustela erminea), 108 water voles (Arvicola amphibius), 39 bank voles (Myodes glareolous), 10 field voles (Microtus agrestis), 15 wood mice (Apodemus sylvaticus), one common shrew (Sorex aranaeus), two pygmy shrews (Sorex minutus), two hedgehogs (Erinaceus europaeus) and 75 Eurasian otters (Lutra lutra). No cases of SARS-CoV-2 were detected in any animals, but a novel minacovirus related to mink and ferret alphacoronaviruses was detected in stoats recently introduced to the Orkney Islands. This group of viruses is of interest due to pathogenicity in ferrets. The impact of this virus on the health of stoat populations remains to be established.

Sarbecoviruses of British horseshoe bats; sequence variation and epidemiology.

Horseshoe bats are the natural hosts of the Sarbecovirus subgenus that includes SARS-CoV and SARS-CoV- 2. Despite the devastating impact of the COVID-19 pandemic, there is still little known about the underlying epidemiology and virology of sarbecoviruses in their natural hosts, leaving large gaps in our pandemic preparedness. Here we describe the results of PCR testing for sarbecoviruses in the two horseshoe bat species (Rhinolophus hipposideros and R. ferrumequinum) present in Great Britain, collected in 2021-22 during the peak of COVID-19 pandemic. One hundred and ninety seven R. hipposideros samples from 33 roost sites and 277 R. ferrumequinum samples from 20 roost sites were tested. No coronaviruses were detected in any samples from R. ferrumequinum whereas 44 and 56 % of individual and pooled (respectively) faecal samples from R. hipposideros across multiple roost sites tested positive in a sarbecovirus-specific qPCR. Full genome sequences were generated from three of the positive samples (and partial genomes from two more) using Illumina RNAseq on unenriched samples. Phylogenetic analyses showed that the obtained sequences belong to the same monophyletic clade, with >95 % similarity to previously-reported European isolates from R. hipposideros. The sequences differed in the presence or absence of accessory genes ORF 7b, 9b and 10. All lacked the furin cleavage site of SARS-CoV-2 spike gene and are therefore unlikely to be infective for humans. These results demonstrate a lack, or at least low incidence, of SARS-CoV-2 spill over from humans to susceptible GB bats, and confirm that sarbecovirus infection is widespread in R. hipposideros. Despite frequently sharing roost sites with R. ferrumequinum, no evidence of cross-species transmission was found.

Using high-resolution LiDAR-derived canopy structure and topography to characterise hibernaculum locations of the hazel dormouse.

The hazel dormouse is predominantly an arboreal species that moves down to the ground to hibernate in the autumn in temperate parts of its distributional ranges at locations not yet well understood. The main objective of this study is to test whether environmental characteristics surrounding hazel dormouse hibernacula can be identified using high-resolution remote sensing and data collected in situ. To achieve this, remotely sensed variables, including canopy height and cover, topographic slope, sky view, solar radiation and cold air drainage, were modelled around 83 dormouse hibernacula in England (n = 62) and the Netherlands (n = 21), and environmental characteristics that may be favoured by pre-hibernating dormice were identified. Data on leaf litter depth, temperature, canopy cover and distance to the nearest tree were collected in situ and analysed at hibernaculum locations in England. The findings indicated that remotely sensed data were effective in identifying attributes surrounding the locations of dormouse hibernacula and when compared to in situ information, provided more conclusive results. This study suggests that remotely sensed topographic slope, canopy height and sky view have an influence on hazel dormice choosing suitable locations to hibernate; whilst in situ data suggested that average daily mean temperature at the hibernaculum may also have an effect. Remote sensing proved capable of identifying localised environmental characteristics in the wider landscape that may be important for hibernating dormice. This study proposes that this method can provide a novel progression from habitat modelling to conservation management for the hazel dormouse, as well as other species using habitats where topography and vegetation structure influence fine-resolution favourability.

Trends and knowledge gaps in field research investigating effects of anthropogenic noise.

Anthropogenic noise is a globally widespread sensory pollutant, recognized as having potentially adverse effects on function, demography, and physiology in wild animals. Human population growth and associated changes in urbanization, transportation, and resource extraction all contribute to anthropogenic noise and are predicted to increase in the coming decades. Wildlife exposure to anthropogenic noise is expected to rise correspondingly. Data collected through field research are uniquely important in advancing understanding of the real-world repercussions of human activity on wildlife. We, therefore, performed a systematic review of literature published from 2008 to 2018 that reported on field investigations of anthropogenic noise impacts. We evaluated publication metrics (e.g., publication rates and journal type), geographical distribution of studies, study subject, and methods used. Research activity increased markedly over the assessment period. However, there was a pronounced geographical bias in research, with most being conducted in North America or Europe, and a notable focus on terrestrial environments. Fewer than one-fifth of terrestrial studies were located in rural areas likely to experience urbanization by 2030, meaning data on ecosystems most likely to be affected by future changes are not being gathered. There was also bias in the taxonomic groups investigated. Most research was conducted on birds and aquatic mammals, whereas terrestrial mammals, reptiles, amphibians, fish, and invertebrates received limited attention. Almost all terrestrial studies examined diurnal species, despite evidence that nocturnality is the prevailing animal activity pattern. Nearly half the studies investigated effects of road or urban noise; the bulk of research was restricted to functional, rather than physiological or demographic consequences. Few experimental studies addressed repercussions of long-term exposure to anthropogenic noise or long-term postexposure effects, and multiple noise types or levels were rarely compared. Tackling these knowledge gaps will be vital for successful management of the effects of increasing wildlife exposure to anthropogenic noise.

Tendencias y Vacíos de Conocimiento en el Trabajo de Campo que Investiga los Efectos del Ruido Antropogénico Resumen El ruido antropogénico es un contaminante sensorial con amplia distribución global. Se le reconoce como un contaminante con efectos adversos potenciales sobre la función, demografía y fisiología de la fauna silvestre. El crecimiento de las poblaciones humanas y los cambios asociados a la urbanización, transporte y extracción de recursos contribuyen al ruido antropogénico y se pronostica que todos incrementarán en las siguientes décadas. Se espera que la exposición de la fauna al ruido antropogénico aumente en correspondencia. Los datos recolectados por medio del trabajo de campo tienen una importancia única en el avance del entendimiento de las repercusiones reales de la actividad humana en la fauna. Por lo tanto realizamos una revisión sistémica de la literatura publicada de 2008 a 2018 en la que se reportaron investigaciones en campo de los impactos del ruido antropogénico. Evaluamos las medidas de publicación (p. ej.: las tasas de publicación y el tipo de revista), la distribución geográfica de los estudios, el sujeto del estudio y los métodos que se utilizaron. La actividad de investigación aumentó de manera marcada a lo largo del periodo de evaluación. Sin embargo, hubo un sesgo geográfico pronunciado en las investigaciones pues la mayoría se realizó en América del Norte o en Europa y hubo un enfoque notable sobre los ambientes terrestres. Menos de la quinta parte de los estudios terrestres estuvieron ubicados en áreas rurales con una probabilidad de sufrir urbanización para el 2030, lo que significa que no se están recopilando datos para los ecosistemas con mayor probabilidad de ser afectados en el futuro. También hubo un sesgo en los grupos taxonómicos investigados. La mayoría de las investigaciones se realizó en aves y en mamíferos acuáticos, mientras que los mamíferos terrestres, los reptiles, los anfibios, los peces y los invertebrados recibieron una atención limitada. Casi todos los estudios terrestres trabajaron con especies diurnas, a pesar de la evidencia existente de que los hábitos nocturnos son el patrón prevaleciente de actividad animal. Casi la mitad de los estudios investigaron los efectos del ruido urbano o de las carreteras; el grueso de las investigaciones estuvo restringido a las consecuencias funcionales y no tanto a las fisiológicas o demográficas. Pocos estudios experimentales trataron el tema de las repercusiones a largo plazo de la exposición al ruido antropogénico o el de los efectos post-exposición a largo plazo. Tampoco encontramos muchos estudios en los que se compararan los tipos o niveles de ruido. Será vital lidiar con estos vacíos de conocimiento para el manejo exitoso de los efectos de la creciente exposición de la fauna al ruido antropogénico.

Hydrogen isotopes reveal evidence of migration of Miniopterus schreibersii in Europe.

BACKGROUND: The Schreiber's bat, Miniopterus schreibersii, is adapted to long-distance flight, yet long distance movements have only been recorded sporadically using capture-mark-recapture. In this study, we used the hydrogen isotopic composition of 208 wing and 335 fur specimens from across the species' European range to test the hypothesis that the species migrates over long distances. RESULTS: After obtaining the hydrogen isotopic composition (δ2H) of each sample, we performed geographic assignment tests by comparing the δ2H of samples with the δ2H of sampling sites. We found that 95 bats out of 325 showed evidence of long-distance movement, based on the analysis of either fur or wing samples. The eastern European part of the species range (Greece, Bulgaria and Serbia) had the highest numbers of bats that had moved. The assignment tests also helped identify possible migratory routes, such as movement between the Alps and the Balkans. CONCLUSIONS: This is the first continental-scale study to provide evidence of migratory behaviour of M. schreibersii throughout its European range. The work highlights the need for further investigation of this behaviour to provide appropriate conservation strategies.

Elevated risk of stillbirth in males: systematic review and meta-analysis of more than 30 million births.

BACKGROUND: Stillbirth rates have changed little over the last decade, and a high proportion of cases are unexplained. This meta-analysis examined whether there are inequalities in stillbirth risks according to sex. METHODS: A systematic review of the literature was conducted, and data were obtained on more than 30 million birth outcomes reported in observational studies. The pooled relative risk of stillbirth was estimated using random-effects models. RESULTS: The crude mean rate (stillbirths/1,000 total births) was 6.23 for males and 5.74 for females. The pooled relative risk was 1.10 (95% confidence interval (CI): 1.07-1.13). The attributable fraction in the whole population was 4.2% (95% CI: 3.70-4.63), and the attributable fraction among male fetuses was 7.8% (95% CI: 7.0-8.66). Study populations from countries with known sex-biased sex selection issues had anomalous stillbirth sex ratios and higher overall stillbirth risks than other countries, reflecting increased mortality among females. CONCLUSIONS: Risk of stillbirth in males is elevated by about 10%. The population-attributable risk is comparable to smoking and equates to approximately 100,000 stillbirths per year globally. The pattern is consistent across countries of varying incomes. Given current difficulties in reducing stillbirth rates, work to understand the causes of excess male risk is warranted. We recommend that stillbirths are routinely recorded by sex. This will also assist in exposing prenatal sex selection as elevated or equal risks of stillbirth in females would be readily apparent and could therefore be used to trigger investigation.

A simple and fast method for estimating bat roost locations.

Bats play a pivotal role in pest control, pollination and seed dispersal. Despite their ecological significance, locating bat roosts remains a challenging task for ecologists. Traditional field surveys are time-consuming, expensive and may disturb sensitive bat populations. In this article, we combine data from static audio detectors with a bat movement model to facilitate the detection of bat roosts. Crucially, our technique not only provides a point prediction for the most likely location of a bat roost, but because of the algorithm's speed, it can be applied over an entire landscape, resulting in a likelihood map, which provides optimal searching regions. To illustrate the success of the algorithm and highlight limitations, we apply our technique to greater horseshoe bat (Rhinolophus ferrumequinum) acoustic data acquired from six surveys from four different UK locations and over six different times in the year. Furthermore, we investigate what happens to the accuracy of our predictions in the case that the roost is not contained within the area spanned by the detectors. This innovative approach to searching rural environments holds the potential to greatly reduce the labour required for roost finding, and, hence, enhance the conservation efforts of bat populations and their habitats.

Multiple novel caliciviruses identified from stoats (Mustela erminea) in the United Kingdom.

The Caliciviridae family, comprising positive-sense RNA viruses, is characterised by its non-enveloped, small virions, broad host range, and notable tendency for host switching. These viruses are primarily associated with gastroenteric disease, though they can lead to haemorrhagic or respiratory infections. Our study employed a metagenomics analysis of faecal samples from stoats (Mustela erminea), identifying two novel calicivirus species, named stoat vesivirus and stoat valovirus. Stoat vesivirus was identified in three samples (ST008, ST006, ST004), exhibiting a genome wide nucleotide identity of approximately 92 %. The complete coding sequences of these samples were 8471 (ST004) and 8322 (ST006) nucleotides in length, respectively. Each comprised three open reading frames (ORF), closely resembling the Vesivirus mink calicivirus (China/2/2016), with 70-72 % similarity in ORF1, 61-62 % in ORF2 and 71 % in ORF3. Phylogenetic analysis robustly supported stoat vesivirus as belonging within the Vesivirus genus. The second calivicirus (stoat valovirus), detected solely in sample ST008, was 6527 nucleotides in length and with complete coding sequences present. It shared highest similarity with St-Valérien swine virus and marmot norovirus HT16, showing 39.5 and 38.8 % protein identity with ORF1 and 43.3 and 42.9 % for VP1. Stoat valovirus is borderline for meeting the ICTV criteria for a new genus, demonstrating 60 % divergence in ORF1 compared to the other valovirus', however it clusters basally within the Valovirus genus, supporting leaving it included in this genus.

Plastic Entanglement Poses a Potential Hazard to European Hedgehogs Erinaceus europaeus in Great Britain.

A questionnaire to gather evidence on the plastic entanglement of the European hedgehog (Erinaceus europaeus) was sent to 160 wildlife rehabilitation centres in Great Britain. Fifty-four responses were received, and 184 individual admissions owing to plastic entanglement were reported. Death was the outcome for 46% (n = 86) of these cases. A high proportion of Britain's hedgehogs enter rehabilitation centres annually (approximately 5% of the national population and potentially 10% of the urban population), providing a robust basis for assessing the minimum impacts at a national level. We estimate that 4000-7000 hedgehog deaths per year are attributable to plastic, with the true rate likely being higher, since many entangled hedgehogs-in contrast to those involved in road traffic accidents-will not be found. Population modelling indicates that this excess mortality is sufficient to cause population declines. Although the scale of the impact is much lower than that attributable to traffic, it is nevertheless an additional pressure on a species that is already in decline and presents a significant welfare issue to a large number of individuals.

Marvellous moths! pollen deposition rate of bramble (Rubus futicosus L. agg.) is greater at night than day.

Widespread concerns about declines of wild pollinating insects has attracted considerable research interest, largely directed towards identifying key nectar sources and assessing the contribution of pollinators towards ecosystem services. However, previous work has almost exclusively focussed on bees and other diurnal invertebrate taxa. This study aimed to assess the relative contribution of diurnal and nocturnal insects to the pollination of bramble (Rubus fruticosus agg.), a common and widespread species aggregate across Europe, which has been identified as a key source of pollen and nectar for diurnal pollinators. Bramble flower visitation rates by diurnal and nocturnal insects were quantified by analysing over 380,000 interval photographs taken over a 3-day period across 10 sites. A pollinator exclusion experiment was also undertaken to assess the importance of diurnal and nocturnal insects for pollination by analysing pollen deposition on 480 bramble stigmas of nocturnally exposed, diurnally exposed and unvisited control flowers across all sites. Flower visitation was significantly higher during the day, comprising 83% of all visits made by a range of taxa. Nocturnal visitation was almost exclusively by moths. Crucially, pollen deposition rates of bramble were significantly higher during the night compared with the day. No relationship was detected between pollen counts and flower visitation rates, suggesting that moths are more efficient pollinators of bramble compared with diurnal insects. Overall, this work provides further evidence of the value of bramble as a resource for pollinators and demonstrates that moths likely play an important role in bramble pollination.

An acoustic-based method for locating maternity colonies of rare woodland bats.

Locating colonies of rare bats can be a time consuming process, as it is often difficult to know where to focus survey effort. However, identifying peaks of bat activity via acoustic monitoring may provide insights into whether a colony is locally present, and help screen out sites with low potential. Using a triage approach, we developed a survey methodology for locating colonies of the woodland-specialist barbastelle bat (Barbastella barbastellus). We investigated whether woodland occupancy by a colony could be predicted by acoustic data, and assessed the influence of survey effort (number of acoustic detectors deployed) on detectability. The methodology was then trialled in citizen science surveys of 77 woodlands, with follow-up radio-tracking surveys by specialists being used to confirm presence or absence. Using Receiver Operating Characteristic (ROC) curve analysis, we found that a threshold of four barbastelle passes recorded by at least one detector within one hour of sunset optimised the balance between the true- and false-positive rates. Subsequently, we found that a minimum survey effort of one detector per 6.25 hectares of woodland was needed to ensure a colony would be detected using this threshold, based on a survey sensitivity of 90%. Radio-tracking surveys in a subset of the woodlands, identified as having a high probability of being occupied by a colony based on acoustic monitoring, confirmed the presence of five previously unknown barbastelle maternity colonies. These results demonstrate that a triage system, in which high probability woodland sites are identified based on acoustic survey data, can be used to prioritise sites for future specialist surveys and conservation action.

Bat responses to climate change: a systematic review.

Understanding how species respond to climate change is key to informing vulnerability assessments and designing effective conservation strategies, yet research efforts on wildlife responses to climate change fail to deliver a representative overview due to inherent biases. Bats are a species-rich, globally distributed group of organisms that are thought to be particularly sensitive to the effects of climate change because of their high surface-to-volume ratios and low reproductive rates. We systematically reviewed the literature on bat responses to climate change to provide an overview of the current state of knowledge, identify research gaps and biases and highlight future research needs. We found that studies are geographically biased towards Europe, North America and Australia, and temperate and Mediterranean biomes, thus missing a substantial proportion of bat diversity and thermal responses. Less than half of the published studies provide concrete evidence for bat responses to climate change. For over a third of studied bat species, response evidence is only based on predictive species distribution models. Consequently, the most frequently reported responses involve range shifts (57% of species) and changes in patterns of species diversity (26%). Bats showed a variety of responses, including both positive (e.g. range expansion and population increase) and negative responses (range contraction and population decrease), although responses to extreme events were always negative or neutral. Spatial responses varied in their outcome and across families, with almost all taxonomic groups featuring both range expansions and contractions, while demographic responses were strongly biased towards negative outcomes, particularly among Pteropodidae and Molossidae. The commonly used correlative modelling approaches can be applied to many species, but do not provide mechanistic insight into behavioural, physiological, phenological or genetic responses. There was a paucity of experimental studies (26%), and only a small proportion of the 396 bat species covered in the examined studies were studied using long-term and/or experimental approaches (11%), even though they are more informative about the effects of climate change. We emphasise the need for more empirical studies to unravel the multifaceted nature of bats' responses to climate change and the need for standardised study designs that will enable synthesis and meta-analysis of the literature. Finally, we stress the importance of overcoming geographic and taxonomic disparities through strengthening research capacity in the Global South to provide a more comprehensive view of terrestrial biodiversity responses to climate change.

Parasites reveal movement of bats between the New and Old Worlds.

The global distribution of bat taxa indicates that the Atlantic and Pacific Oceans are effective barriers to movement between the Old and New Worlds. For instance, one of the major suborders, Yinpterochiroptera, has an exclusively Old World distribution, and within the other, Yangochiroptera, no species and only five genera are common to both. However, as bats are sometimes blown out to sea, and have colonised isolated islands, occasional natural movement between the New and Old Worlds does appear to be possible. Here we identify new genotypes of a blood parasite, Trypanosoma dionisii, in Old World bats that are closely related to South American strains. Using highly conservative calibration points, divergence of Old and New World strains is estimated to have occurred 3.2-5.0 million years ago (MYA), depending on the method used (upper 95% CL for maximum time 11.4MYA). The true date of divergence is likely to be considerably more recent. These results demonstrate that taxon-specific parasites can indicate historical movements of their hosts, even where their hosts may have left no lasting phylogenetic footprint.

Ingestion of plastics by terrestrial small mammals.

The exposure of wildlife to waste plastic is widely recognised as an issue for aquatic ecosystems but very little is known about terrestrial systems. Here, we addressed the hypothesis that UK small mammals are ingesting plastics by examining faecal samples for the presence of plastic using micro Fourier Transform infrared microscopy. Plastic polymers were detected in four out of the seven species examined (European hedgehog (Erinaceus europaeus), wood mouse (Apodemus sylvaticus); field vole (Microtus agrestis); brown rat (Rattus norvegicus)). Ingestion occurred across species of differing dietary habits (herbivorous, insectivorous and omnivorous) and locations (urban versus non-urban). Densities excreted were comparable with those reported in human studies. The prevalence of confirmed plastics in the 261 faecal samples was 16.5 % (95 % CI 13 %, 22 %). Most (70 %) of the 60 plastic fragments were <1 mm (microplastics). Polyester, likely to be derived from textiles, accounted for 27 % of the fragments and was found in all plastic-positive species except for the wood mouse. The high prevalence of polyester in terrestrial ecosystems was unexpected and suggests that evaluation is needed of practices likely to transfer this plastic into the environment (such as sewage sludge application to farmland). Polynorbornene, which is likely to be derived from tyre wear, and polyethylene were also commonly detected polymers. 'Biodegradable' plastics formed 27 % (n = 12) of the particles found in wild mammal faeces, warranting further research to assess their persistence in the environment.

Passing rail traffic reduces bat activity.

Rail transport is expanding, with a global increase in infrastructure of up to one-third predicted by 2050. Greater reliance on rail is expected to benefit the environment at a planetary level, by mitigating transport-related carbon emissions. However, smaller-scale, more direct consequences for wildlife are unclear, as unlike roads, railway impacts on animal ecology are rarely studied. As a group, bats frequently interact with transport networks due to their broad distribution and landscape-scale movements. Additionally, their nocturnality, and use of echolocation mean bats are likely to be affected by light and noise emitted by trains. To investigate whether passing trains affect bat activity levels, we monitored the two most abundant UK species using ultrasonic detectors at 12 wooded rail-side sites in southern England. Activity fell by ≥ 30-50% each time a train passed, for at least two minutes. Consequently, activity was reduced for no less than one-fifth of the time at sites with median rail traffic, and two-thirds or more of the time at the busiest site. Such activity changes imply repeated evasive action and/or exclusion from otherwise favourable environments, with potential for corresponding opportunity or energetic costs. Hence, disturbance by passing trains may disadvantage bats in most rail-side habitats.

Can effective population size estimates be used to monitor population trends of woodland bats? A case study of Myotis bechsteinii.

Molecular approaches to calculate effective population size estimates (Ne) are increasingly used as an alternative to long-term demographic monitoring of wildlife populations. However, the complex ecology of most long-lived species and the consequent uncertainties in model assumptions means that effective population size estimates are often imprecise. Although methods exist to incorporate age structure into Ne estimations for long-lived species with overlapping generations, they are rarely used owing to the lack of relevant information for most wild populations. Here, we performed a case study on an elusive woodland bat, Myotis bechsteinii, to compare the use of the parentage assignment Ne estimator (EPA) with the more commonly used linkage disequilibrium (LD) Ne estimator in detecting long-term population trends, and assessed the impacts of deploying different overall sample sizes. We used genotypic data from a previously published study, and simulated 48 contrasting demographic scenarios over 150 years using the life history characteristics of this species The LD method strongly outperformed the EPA method. As expected, smaller sample sizes resulted in a reduced ability to detect population trends. Nevertheless, even the smallest sample size tested (n = 30) could detect important changes (60%-80% decline) with the LD method. These results demonstrate that genetic approaches can be an effective way to monitor long-lived species, such as bats, provided that they are undertaken over multiple decades.

Peaks in bat activity at turbines and the implications for mitigating the impact of wind energy developments on bats.

Wind turbines are a relatively new threat to bats, causing mortalities worldwide. Reducing these fatalities is essential to ensure that the global increase in wind-energy facilities can occur with minimal impact on bat populations. Although individual bats have been observed approaching wind turbines, and fatalities frequently reported, it is unclear whether bats are actively attracted to, indifferent to, or repelled by, the turbines at large wind-energy installations. In this study, we assessed bat activity at paired turbine and control locations at 23 British wind farms. The research focussed on Pipistrellus species, which were by far the most abundant bats recorded at these sites. P. pipistrellus activity was 37% higher at turbines than at control locations, whereas P. pygmaeus activity was consistent with no attraction or repulsion by turbines. Given that more than 50% of bat fatalities in Europe are P. pipistrellus, these findings help explain why Environmental Impact Assessments conducted before the installation of turbines are poor predictors of actual fatality rates. They also suggest that operational mitigation (minimising blade rotation in periods of high collision risk) is likely to be the most effective way to reduce collisions because the presence of turbines alters bat activity.