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Flowering plants have evolved an extraordinary variety of signalling traits to attract their pollinators. Most flowers rely on visual and chemical signals, but some bat-pollinated plants have evolved passive acoustic floral signals. All known acoustic flower signals rely on the same principle of increased sonar reflectivity. Here, we describe a novel mechanism that relies on increased absorption of the area surrounding the flower. In a bat-pollinated cactus (Espostoa frutescens) we found a hairy inflorescence zone, a so-called cephalium. Flowers solely emerge out of this zone. We measured the echoes of cephalia, flowers and unspecialized column surfaces and recorded echolocation calls of approaching bats. We found that the cephalium acts as a strong ultrasound absorber, attenuating the sound by −14 dB. The absorption was highest around the echolocation call frequencies of approaching bats. Our results indicate that, instead of making flowers more reflective, plants can also evolve structures to attenuate the background echo, thereby enhancing the acoustic contrast with the target.

Individual-based networks provide the building blocks for community-level networks. However, network studies of bats and their parasites have focused only on the species level. Intrapopulation variation may allow certain host individuals to play important roles in the dynamics of the parasites. Therefore, we evaluated how the variation in host sex, body size, ectoparasite abundance and co-occurrence configure individual-based networks of the lesser bulldog bat Noctilio albiventris and bat flies. We expected bat individuals with greater body mass and forearms acting as the core in the network. We also expected males to play a more important role in the network. We sampled a network of N. albiventris bat individuals and their bat flies to describe the structure of an antagonistic individual-based network. We aimed to identify the most relevant bat individuals in the network, focusing on the implications inherent to each of the following approaches: (i) core-periphery organization; (ii) modularity; (iii) species level metrics; and (iv) the main ecological driver of bat individual roles in the network, using niche-based predictors (body mass, forearm and sex). We showed that a network of N. albiventris individuals and their bat flies had low modularity containing a persistent nucleus of individuals and bat flies with well-established interactions. Male individuals with greater body mass played an important role in the network, while for females neither mass nor forearm length were important predictors of their role in the network. Finally, individuals with a high abundance of Paradyschiria parvula played a core role. These results provide an alternative perspective to understand the patterns and mechanisms of interspecific interactions between parasites on the host, as well as sex-biased parasitism.

The study of animal–habitat interactions is of primary importance for the formulation of conservation recommendations. Flying, gliding, and climbing animals have the ability to exploit their habitat in a three‐dimensional way, and the vertical canopy structure in forests plays an essential role for habitat suitability. Forest bats as flying mammals may seasonally shift their microhabitat use due to differing energy demands or changing prey availability, but the patterns are not well understood. We investigated three‐dimensional and seasonal habitat use by insectivorous bats in a temperate lowland old‐growth forest, the Belovezhskaya Pushcha in Belarus. We acoustically sampled broadleaved and mixed coniferous plots in the forest interior and in gaps in three heights during two reproductive periods (pregnancy/lactation vs. postlactation). In canopy gaps, vertical stratification in bat activity was less pronounced than in the forest interior. Vertical activity patterns differed among species. The upper canopy levels were important foraging habitats for the open‐space forager guild and for some edge‐space foragers like the Barbastelle bat Barbastella barbastellus and the soprano pipistrelle Pipistrellus pygmaeus. Myotis species had highest activity levels near the ground in forest gaps. Moreover, we found species‐dependent seasonal microhabitat shifts. Generally, all species and species groups considered except Myotis species showed higher activity levels during postlactation. Myotis species tended toward higher activity in the forest interior during postlactation. P. pygmaeus switched from high activity levels in the upper canopy during pregnancy and lactation to high activity levels near the ground during postlactation. We conclude that a full comprehension of forest bat habitat use is only possible when height in canopy and seasonal patterns are considered., We investigated three‐dimensional and seasonal habitat use by insectivorous bats in a temperate lowland old‐growth forest. We identified guild‐ and species‐specific differences in canopy height use and species‐dependent seasonal microhabitat shifts that can be explained by ecomorphological adaptations.

The vampire bat Desmodus rotundus is the main transmitter of domestic herbivorous rabies, which causes economic losses in cattle raising, being a serious public health problem. The use of Geographic Information Systems (GIS) allows the spatial monitoring of these bats shelters, which is an efficient way to prevent and control rabies. This study located shelters of D. rotundus in the Eastern Center region of São Paulo state and identified the types of shelters used (natural or artificial), their proximity to water, sexual composition, and population estimated of the colonies. Searches were carried out by colonies of vampire bats in natural and artificial shelters during 2002 to 2004, covering 18 municipalities. After located, the shelters were georeferenced, being recorded the nature of the shelter (natural or artificial), use (shelters of males, maternities, digestive) and estimated population. The data were incorporated into a GIS, producing a thematic map of the shelter’s location and their distance from the local water bodies. There were found 1.567 D. rotundus distributed in 94 shelters, where only six shelters (6.38%) were natural (caves). Most shelters (79.78%) were sparsely populated, with up to 15 bats, including male shelters (46 shelters) and 30 maternities (63.82% of maternities). Five shelters (5.37%) had between 50 and 100 bats and only two shelters (2.15%) had a population greater than 100 bats. Six shelters (6.38%) were inhabited houses, which is a concern for public health, as these may constitute a source of dangerous contamination for domestic and human carnivores. All the shelters were at a distance of up to 2 km of rivers or streams. The high percentage of artificial shelters found is a consequence of the intensification of the anthropic changes that increase the supply of food and shelter to D. rotundus, which associated with a large drainage network favors the dispersion of this species of bat in the region. The proximity of all D. rotundus shelters to the drainage network corroborates other studies in São Paulo state, where the areas close to the main rivers generally favor the existence of a larger number of shelters.

Small wind turbines (SWTs) have become increasingly common in several European countries, but knowledge of their impact on wildlife, especially bats, remains relatively scarce. We applied an operational experiment at 10 SWTs in Northern Germany to determine the bat species commonly found at those SWT sites and whether the operational state of the SWT affects bat activity or behavior. During the experiment, the SWT operational state (“ON”, “OFF”) was altered and the flight trajectories of bats around the SWTs were documented using a specifically designed 3D camera with a high spatial resolution able to capture collisions with the structures. Several bat species were detected in the close vicinity (20 m) of the SWTs at all study sites. The bat species group “Nyctaloids” dominated bat acoustic activity at most SWTs, followed by Pipistrellus pipistrellus and P. nathusii. Only 41 of the 499 flight trajectories approached the nacelle closer than 10 m, including one that passed the rotor blades directly. Generally, there was no evidence of collisions nor was there an influence of operation mode on either bat acoustic activity levels or the distance of bat flight trajectories to the nacelle. However, we strongly caution that the results of our study cannot be generalized to other landscapes, weather conditions, bat species, or SWT types.

Funder: Queensland Government Accelerate Postdoctoral Research Fellowship, Outbreaks of infectious viruses resulting from spillover events from bats have brought much attention to bat‐borne zoonoses, which has motivated increased ecological and epidemiological studies on bat populations. Field sampling methods often collect pooled samples of bat excreta from plastic sheets placed under‐roosts. However, positive bias is introduced because multiple individuals may contribute to pooled samples, making studies of viral dynamics difficult. Here, we explore the general issue of bias in spatial sample pooling using Hendra virus in Australian bats as a case study. We assessed the accuracy of different under‐roost sampling designs using generalized additive models and field data from individually captured bats and pooled urine samples. We then used theoretical simulation models of bat density and under‐roost sampling to understand the mechanistic drivers of bias. The most commonly used sampling design estimated viral prevalence 3.2 times higher than individual‐level data, with positive bias 5–7 times higher than other designs due to spatial autocorrelation among sampling sheets and clustering of bats in roosts. Simulation results indicate using a stratified random design to collect 30–40 pooled urine samples from 80 to 100 sheets, each with an area of 0.75–1 m2, and would allow estimation of true prevalence with minimum sampling bias and false negatives. These results show that widely used under‐roost sampling techniques are highly sensitive to viral presence, but lack specificity, providing limited information regarding viral dynamics. Improved estimation of true prevalence can be attained with minor changes to existing designs such as reducing sheet size, increasing sheet number, and spreading sheets out within the roost area. Our findings provide insight into how spatial sample pooling is vulnerable to bias for a wide range of systems in disease ecology, where optimal sampling design is influenced by pathogen prevalence, host population density, and patterns of aggregation.

Bats serve as natural hosts of Pteropine orthoreovirus (PRV), an emerging group of bat-borne, zoonotic viruses. Bats appear to possess unique innate immune system responses that can inhibit viral replication, thus reducing clinical symptoms. We examined the innate immune response against PRV and assessed viral replication in cell lines derived from four bat species (Miniopterus fuliginosus, Pteropus dasymallus, Rhinolophus ferrumequinum, and Rousettus leschenaultii), one rodent (Mesocricetous auratus), and human (Homo sapiens). The expression levels of pattern recognition receptors (PRRs) (TLR3, RIG-I, and MDA5) and interferons (IFNB1 and IFNL1) were higher and PRV replication was lower in cell lines derived from M. fuliginosus, R. ferrumequinum, and R. leschenaultii. Reduction of IFNB1 expression by the knockdown of PRRs in the cell line derived from R. ferrumequinum was associated with increased PRV replication. The knockdown of RIG-I led to the most significant reduction in viral replication for all cell lines. These results suggest that RIG-I production is important for antiviral response against PRV in R. ferrumequinum. Supplementary Information The online version contains supplementary material available at 10.1007/s11262-021-01865-6.

Geographical barriers, distance, and environmental gradients may determine variation in species composition of bat assemblages in tropical regions. For example, bats assume a wide variety of foraging strategies, dietary traits, different flight abilities, and New World leaf-nosed bats (Phyllostomidae) are among the most functionally diverse family of bats. Nonetheless, this variation remains uncharacterized in Honduras. Our study investigated the relationship of environmental and climatic variables that influence leaf-nosed bat assemblages in terms of alpha and beta taxonomic and functional diversity. From February 2015 to May 2019, we sampled 56 sites and captured 1086 phyllostomid bats. We found that taxonomic alpha diversity decreased with elevation, and that functional alpha diversity decreased with elevation and humidity. Changes in taxonomic β-diversity were associated with elevation and changes in functional β-diversity were associated with humidity, elevation, and precipitation. Our findings suggest that elevation is the key environmental variable influencing New World leaf-nosed bat assemblages in Honduras, and even though species composition varies among different habitats, the functional composition of assemblages remains similar.

Before the arrival of white-nose syndrome in North America, the northern long-eared bat (Myotis septentrionalis) was a common cavity-roosting bat species in central Appalachian hardwood forests. Two successive prescribed burns on the Fernow Experimental Forest, West Virginia, in 2008 and 2009, were shown to positively affect maternity colony day-roost availability and condition in the near-term. However, whether immediate benefits were temporary and if burned forests actually experienced an accelerated loss of trees and snags possibly suitable for bats more than background loss in unburned forests became an important question following the species’ threatened designation. In 2016, we revisited 81 of 113 northern long-eared bat maternity colony day-roosts initially discovered in 2007–2009 with the objective of ascertaining if these trees and snags were still standing and thus potentially “available” for bat use. Initial tree or snag stage condition class and original year of discovery were contributory factors determining availability by 2016, whereas exposure to prescribed fire and tree/snag species decay resistance were not. Because forest managers may consider using habitat enhancement to improve northern long-eared bat survival, reproduction, and juvenile recruitment and must also protect documented day-roosts during forestry operations, we conclude that initial positive benefits from prescribed burning did not come at the expense of subsequent day-roost loss greater than background rates in these forests at least for the duration we examined.

The mysterious predator–prey interaction between bats and nocturnally migrating birds is a very rare and incredible process in natural ecosystems. So far only three avivorous bat species, including two noctule bats (Nyctalus lasiopterus and Nyctalus aviator) and the great evening bat (Ia io), are known to regularly prey on songbirds during nocturnal avian migration. The information related to the diversity and the characteristics of the birds as prey and the hunting strategy in both species of noctule bats are already clear. However, the diversity of bird prey in the diet of I. io as confirmed by molecular identification remains unknown. Moreover, like hunting insects, it remains unclear whether the avivorous bats opportunistically prey on birds. Here, we used DNA metabarcoding to investigate the bird prey composition, diversity, and choice in diets of I. io. We found I. io consumed 22 species of seven families from Passeriformes with a body mass of 6–19 g, and preferentially selected small‐sized passerine birds for optimizing the benefit/risk trade‐off. Moreover, most of the species preyed upon were migratory birds, while four species were local resident birds, indicating that I. io may adopt both aerial‐hawking and gleaning strategies on songbirds as do the other two noctules. Further, I. io body mass did not influence in prey choice and predation richness on birds, suggesting I. io is an opportunistic avivorous predator. This study provides novel insights into the avian dietary ecology of I. io and completes the analysis of predator/prey interaction between three avivorous bats and nocturnally migrating birds. Our results also indicate bat predation on birds which occurs as an act of ecological opportunity may subject bats to intense natural selection pressure, causing them access to the new diet‐defined adaptive zones., We used DNA metabarcoding to investigate the bird prey composition, diversity, and choice in diets of the avivorous bat, Ia io. We found I. io consumed 22 species of seven families from Passeriformes. Moreover, I. io may adopt both aerial‐hawking and gleaning strategies on songbirds as do the other two noctules. Ia io body mass did not influence in prey choice and predation richness on birds, suggesting I. io is an opportunistic avivorous predator. Our work provides novel insights into the avian dietary ecology of I. io and completes the analysis of predator/prey interaction between three avivorous bats and nocturnally migrating birds.

Mature forest is a key resource for hollow-using bats, but its importance in shaping where bats roost during breeding is not well understood. This lack of understanding limits the ability of forest managers to make informed decisions on the type, amount and spatial arrangement of mature forest to retain for bats in areas used for timber production. Using radio-telemetry, day roosts of three sympatric hollow-using bat species – the chocolate wattled bat (Chalinolobus morio), the Tasmanian long-eared bat (Nyctophilus sherrini) and the lesser long-eared bat (Nyctophilus geoffroyi) – were located in two forested landscapes in south-eastern Tasmania, Australia. By radio-tracking 24 bats in the maternity season, 76 roosts were located, with interspecific variation in roosting preferences evident at the roost, patch and landscape scale. Maternal colonies showed a clear selection for roosting in areas of the landscape containing the highest availability of mature forest, with smaller patches, strips and individual trees used to a greater extent for roosting in the landscape where mature forest was scarce. These findings showcase the importance of retaining mature forest at multiple spatial scales for hollow-using bats.

The bat fly genus Ascodipteron Adensamer, 1896 currently contains 15 species, all of which occur in tropical and subtropical areas of the Eastern Hemisphere. A new species of endoparasitic bat fly, Ascodipteron sanmingensis sp. nov., was collected from the Great Himalayan Leaf-nosed Bat, Hipposideros armiger (Hodgson, 1853), during ecological studies on bats in Fujian, China. A new species, Ascodipteron sanmingensis sp. nov., is described, based on dealate neosomic females and is supported by molecular data from a 368 bp fragment of the cytochrome B (Cytb) gene. Habitus and diagnostic details, as well as the attachment sites on the host, are documented with photographs. A detailed comparison of the new species with related species is provided and the new species is accommodated in the most recent key to the world species of Ascodipteron.

Using questionnaires and serologic testing, we evaluated bat and lyssavirus exposure among persons in an area of Nigeria that celebrates a bat festival. Bats from festival caves underwent serologic testing for phylogroup II lyssaviruses (Lagos bat virus, Shimoni bat virus, Mokola virus). The enrolled households consisted of 2,112 persons, among whom 213 (10%) were reported to have ever had bat contact (having touched a bat, having been bitten by a bat, or having been scratched by a bat) and 52 (2%) to have ever been bitten by a bat. Of 203 participants with bat contact, 3 (1%) had received rabies vaccination. No participant had neutralizing antibodies to phylogroup II lyssaviruses, but >50% of bats had neutralizing antibodies to these lyssaviruses. Even though we found no evidence of phylogroup II lyssavirus exposure among humans, persons interacting with bats in the area could benefit from practicing bat-related health precautions.

P[3] rotavirus (RV) has been identified in many species, including human, simian, dog, and bat. Several glycans, including sialic acid, histo-blood group antigens (HBGAs) are reported as RV attachment factors. The glycan binding specificity of different P[3] RV VP8*s were investigated in this study. Human HCR3A and dog P[3] RV VP8*s recognized glycans with terminal sialic acid and hemagglutinated the red blood cells, while bat P[3] VP8* showed neither binding to glycans nor hemagglutination. However, the bat P[3] VP8* mutant of C189Y obtained the ability to hemagglutinate the red blood cells, while human P[3] HCR3A/M2-102 mutants of Y189C lost the ability. Sequence alignment and structural analysis indicated that residue 189 played an important role in the ligand recognition and may contribute to the cross-species transmission. Structural superimposition exhibited that bat P[3] VP8* model was quite different from the simian P[3] Rhesus rotavirus (RRV) P[3] VP8*, indicating that bat P[3] RV was relatively distinct and partially contributed to the no binding to tested glycans. These results promote our understanding of P[3] VP8*/glycans interactions and the potential transmission of bat/human P[3] RVs, offering more insight into the RV infection and prevalence.

Background Inaccurate diagnosis of encephalitis is a major issue as immunosuppressive treatments can be deleterious in case of viral infection. The European bat lyssavirus type 1 (EBLV-1), a virus related to rabies virus, is endemic in European bats. No human case has yet been reported in Western Europe. A 59-year-old patient without specific past medical history died from encephalitis. A colony of bats lived in an outbuilding of his house. No diagnosis was made using standard procedures. Methods We used a next generation sequencing (NGS) based transcriptomic protocol to search for pathogens in autopsy samples (meninges and brain frontal lobe). Results were confirmed by polymerase chain reaction (PCR) and by antibody testing in serum. Immunochemistry was used to characterize inflammatory cells and viral antigens in brain lesions. Cells and mice were inoculated with brain extracts for virus isolation. Results The patient’s brain lesions were severe and diffuse in white and gray matter. Perivascular inflammatory infiltrates were abundant and rich in plasma cells. NGS identified European bat lyssavirus type 1a in brain, which was confirmed by PCR. A high titer of neutralizing antibodies was found in serum. No viral antigen was detected, and the virus could not be isolated by cell culture or by mouse inoculation. Conclusions The patient died from European bat lyssavirus type 1a infection. NGS was key to identifying this unexpected viral etiology in an epidemiological context that did not suggest rabies. People exposed to bats should be strongly advised to be vaccinated with rabies vaccines, which are effective against EBLV-1.

The free-tailed bat (Tadarida brasiliensis) likely migrates from the southwestern USA and northern Mexico to the south of Mexico to spend the winter in the Cueva San Francisco (CSF), which is the southernmost known roost of the species. In this study, we examined colony size and composition of the free-tailed bats at the CSF for two annual cycles to know if these parameters fluctuate throughout the year and whether these fluctuations indicate that the CSF is a winter roost. From February 2018 to November 2019, we conducted monthly observations and captured bats with a mist net of 12 × 2.6 m to determine sex, age, reproductive status, and relative abundance. The duration of the emergence flight (DEF) was also recorded. We detected significant fluctuations in colony size that were caused by the movement of pregnant females in spring, lactating and post-lactating females and males in summer, and by females and males in autumn and winter. The CSF was occupied all year-round by females and males. Our results indicate that the cave is a winter roost for females and males, a transitional roost for pregnant females that form their maternity colony elsewhere in summer, and a temporary roost for males in summer. We suggest that the CSF is crucial for the conservation of the free-tailed bat.

Severe acute respiratory syndrome coronavirus 2 did not replicate efficiently in 13 bat cell lines, whereas severe acute respiratory syndrome coronavirus replicated efficiently in kidney cells of its ancestral host, the Rhinolophus sinicus bat, suggesting different evolutionary origins. Structural modeling showed that RBD/RsACE2 binding may contribute to the differential cellular tropism.

Bats are considered ideal reservoirs for zoonotic viruses with emerging capabilities over the past two decades and spotted evidence points out that they may play a role as a reservoir host for SARS-CoV-2. To investigate the possible role of bats as part of SARS-CoV-2 anthropozoonotic spill-over infections in Egypt, a total of 800 samples obtained from 200 Egyptian fruit bats (Rousettus aegyptiacus) were tested for SARS-CoV-2 using quantitative RT-PCR assay (RT-qPCR). RT-qPCR analysis of RNA extracted from bat tissues showed no positive results for SARS-CoV-2 nucleic acid. These findings suggest that during the study period, the Rousettus aegyptiacus bat was not a reservoir or amplifying host for SARS-CoV-2 infection in Egypt. The lack of SARS-CoV-2 nucleic acid in Egyptian fruit bats is thought to make a significant contribution to SARS-CoV-2 epidemiology.

In Australia, there are at least 50 000 derelict mines, many of which provide habitat for cave-roosting bats. Grating of derelict mines, be it horizontal (adits) or vertical (shafts) drives, is commonly undertaken to prevent human access, though longer-term responses of bats are largely unknown. We assessed the long-term (2–20 years) effects of grating on bats by documenting trends in emergence activity and bat abundance at grated and ungrated derelict mines and quantified behavioural responses of bats in autumn and winter. Emergence activity was dominated by the eastern horseshoe bat (Rhinolophus megaphyllus) with limited activity of other less manoeuvrable species. Both emergence activity and minimum colony size at horizontal adits were 8–9 times greater than at vertical shafts, with bats observed emerging from only 2 of 13 shafts. Emergence activity and minimum colony size were 7–10 times greater at adits with ‘bat friendly’ grating (horizontal bars with spacing >125 mm) than at other treatments (ungrated adits and adits with standard grating). In winter, there were 4–11 times more aborted exit attempts per bat at adits with ‘bat friendly’ grating compared with other treatments, which corresponded to greater emergence activity. Emergence activity and minimum colony size were not related to spacing between bars or time since grating, indicating rapid habituation by R. megaphyllus. However, circling at grates continued for many years and bentwing bats (Miniopterus spp.) made little use of these sites. Bat-friendly grates appear to be an effective management option for R. megaphyllus, but alternatives need to be trialled for other species.

Dispersal plays an important role in the ecological and evolutionary processes of natural populations. Mating behavior (or mating system) is a critical factor shaping dispersal patterns and extents in social mammals, sometimes driving the evolution of sex-biased dispersal. Using molecular markers with contrasting modes of inheritance (mitochondrial DNA and nuclear microsatellites), we determined the population genetic structure and evolutionary history of the great horseshoe bat, Rhinolophus ferrumequinum inhabiting eleven national parks of South Korea, being known as a biodiversity hotspot. Despite apparent matrilineal structure observed over space, there was weak nuclear geographic structure, suggesting female philopatry with male-biased dispersal. The analyses indicated the signal of nonrandom mating (i.e. inbreeding), which is at least partly due to female’s sedentary lifestyle. The large-scale phylogenetic analysis revealed unexpected deep divergence among three distinct clades (Southwest China, East China, and Northeast Asia including South Korea), suggesting these may possibly represent cryptic species complex in R. ferrumequinum. Our findings of sex differences in dispersal in R. ferrumequinum inform conservation managements to enhance the population connectivity among the national parks through promoting female dispersal. Our study also highlights cryptic species diversity in a temperate bat that should have a priority for conservation.

Bats as flying mammals are potent vectors and natural reservoir hosts for many infectious viruses, bacteria, and fungi, also detected in their excreta such as guano. Accelerated deforestation, urbanization, and anthropization hastily lead to overpopulation of the bats in urban areas allowing easy interaction with other animals, expansion, and emergence of new zoonotic disease outbreaks potentially harmful to humans. Therefore, getting new insights in the microbiome of bat guano from different places represents an imperative for the future. Furthermore, the use of novel high-throughput sequencing technologies allows better insight in guano microbiome and potentially indicated that some species could be typical guano-dwelling members. Bats are well known as a natural reservoir of many zoonotic viruses such as Ebola, Nipah, Marburg, lyssaviruses, rabies, henipaviruses, and many coronaviruses which caused a high number of outbreaks including ongoing COVID-19 pandemic. Additionally, many bacterial and fungal pathogens were identified as common guano residents. Thus, the presence of multi-drug-resistant bacteria as environmental reservoirs of extended spectrum β-lactamases and carbapenemase-producing strains has been confirmed. Bat guano is the most suitable substrate for fungal reproduction and dissemination, including pathogenic yeasts and keratinophilic and dimorphic human pathogenic fungi known as notorious causative agents of severe endemic mycoses like histoplasmosis and fatal cryptococcosis, especially deadly in immunocompromised individuals. This review provides an overview of bat guano microbiota diversity and the significance of autochthonous and pathogenic taxa for humans and the environment, highlighting better understanding in preventing emerging diseases. Key points Bat guano as reservoir and source for spreading of autochthonous and pathogenic microbiota Bat guano vs. novel zoonotic disease outbreaks Destruction of bat natural habitats urgently demands increased human awareness

Investigating factors that promote group living in animals can help us to understand the evolution of sociality. The dark woolly bat, Kerivoula furva, forms small groups and uses furled leaves of banana (Musa formosana) as day roosts in subtropical Taiwan. In this study, we reported on the roosting ecology and social organization of K. furva. We examined whether ecological constraints, demographic traits, and physiological demands contributed to its sociality. From July 2014 to May 2016, we investigated the daily roost occupation rate, group size, and composition of each roost, and we calculated association indices in pairs. The results showed K. furva lived in groups throughout the year, and the average daily roost occupation rate was approximately 6.7% of all furled leaves that were suitable for roosting. The size of roosting groups of adults in each roost varied between 1 and 13; group size was independent of air temperature during both reproductive and nonreproductive seasons. The vast majority of roosting groups was composed of females and their young, and males frequently roosted solitarily or in a bachelor group. Forty adult bats were captured ≥4 times during the study period. The association indices in pairs of these 40 bats ranged between 0 and 0.83 with an average of 0.05 ± 0.14 (n = 780). The average association index of female–female pairs was significantly higher than that of female–male pairs and male–male pairs. Based on the association indices, the 40 bats were divided into seven social groups with social group sizes that varied between 2 and 10. Despite changing day roosts frequently, the relatively stable social bonds were maintained year‐round. Our results that groups of K. furva were formed by active aggregation of multiple generation members supported the demographic traits hypothesis.

The lesser long-nosed bat (Leptonycteris yerbabuenae Martínez & Villa-R, 1940) is a specialized nectar feeding species found from southern USA to Nicaragua in Central America, mostly in dry forest. We sampled bats using mist nets and Anabat detectors, and also looked for them at refuges and other sites in Honduras from 2011 to 2016. The lesser long-nosed bat is known in Honduras from only two localities in the southern dry forests below 100 m elevation, and there are no recent records of this species in the country. Our objective is to report new records on distribution and habitat of the lesser long-nosed bat in Honduras. We found eight lesser long-nosed bats at Cerro de Hula, Francisco Morazán department in 2012, and 10 at La Anonilla, Choluteca department, southern Honduras in 2015. Based on these 18 individuals of the lesser long-nosed bat, we report two new localities in Honduras, an altitude record, and the use of another habitat other than the dry forest. The highest point registered was at 1710 m a.s.l. in pastureland with forest remnants in an area heavily impacted by human activities. The new localities are found in the Subtropical Moist Forest. Populations of long-nosed bats in Honduras are probably resident and may include altitudinal movements. Although this species has been described widely in North America, its behavior in Honduras is practically unknown. It is a key species for the tequila and mezcal industry, but its range extends beyond the tequila production area, where it maintains a key role as a pollinator and link between habitats. As a result, research and conservation efforts should be an international goal.

Feeding exclusively on blood, vampire bats represent the only obligate sanguivorous lineage among mammals. To uncover genomic changes associated with adaptations to this unique dietary specialization, we generated a new haplotype-resolved reference-quality genome of the common vampire bat (Desmodus rotundus) and screened 26 bat species for genes that were specifically lost in the vampire bat lineage. We discovered previously-unknown gene losses that relate to metabolic and physiological changes, such as reduced insulin secretion (FFAR1,SLC30A8), limited glycogen stores (PPP1R3E), and a distinct gastric physiology (CTSE). Other gene losses likely reflect the biased nutrient composition (ERN2,CTRL) and distinct pathogen diversity of blood (RNASE7). Interestingly, the loss ofREP15likely helped vampire bats to adapt to high dietary iron levels by enhancing iron excretion and the loss of the 24S-hydroxycholesterol metabolizing enzymeCYP39A1could contribute to their exceptional cognitive abilities. Finally, losses of key cone phototransduction genes (PDE6H,PDE6C) suggest that these strictly-nocturnal bats completely lack cone-based vision. These findings enhance our understanding of vampire bat biology and the genomic underpinnings of adaptations to sanguivory.

As practitioners of mitigation and conservation of bats, we think use of artificial bat roosts contribute to bat conservation and should be encouraged. Problems with boxes identified by Reed and O'Keefe also exist with natural roosts, and they are more readily studied and managed with artificial than natural roosts. Use of boxes also provides an opportunity for citizen science, but more importantly engenders citizen conservation.

Three rod-shaped, Gram-stain-positive, and catalase-positive, phenotypically closely related isolates (HY052T, HY050, and HY045) were obtained from fecal samples collected from bats in Guangxi province and Chongqing city of China. Circular, smooth, light-yellow colonies appeared on brain heart infusion plate after 24–48 h incubation at 28°C. The optimal pH for growth was between 6.0 and 7.5. Based on 16S rRNA, the three isolates were phylogenetically related to Agromyces terreus DS-10T, Agromyces aureus AR33T, Agromyces salentinus 20-5T, Agromyces allii UMS-62T, Agromyces lapidis CD55T, and Agromyces italicus CD1T. Moreover, based on 296 core genes, the phylogenomic tree indicated that the three isolates clustered together, closest to Agromyces cerinus VKM Ac-1340T and Agromyces fucosus VKM Ac-1345T but separated distantly from other Agromyces species. The average nucleotide identity values between strain HY052T and other Agromyces species ranged from 79.3% to 87.9%, lower than the 95–96% threshold. Furthermore, the genome of strain HY052T contains a circular chromosome of 3,437,203 bp with G + C content of 69.0 mol%. Main fatty acids were anteiso-C15:0 and anteiso-C17:0. The polar lipids comprised diphosphatidylglycerol, phosphatidylglycerol, and unidentified glycolipids. Rhamnose, ribose, and glucose were the primary cell wall sugars. The major peptidoglycan amino acids included alanine, glutamic acid, glycine, and 2,4-diaminobutyric acid. An additional remarkable difference from other Agromyces species is that MK-12 was the sole menaquinone in strain HY052T. Based on results from the polyphasic characterizations performed in this study, our isolates are proposed to be members of a novel species in genus Agromyces, named Agromyces laixinhei. The type strain is HY052T (= CGMCC 1.17175T = JCM 33695T). Electronic Supplementary Material Supplementary material is available in the online version of this article at 10.1007/s12275-021-0546-5.

The emergence of SARS-CoV-2, a coronavirus with suspected bat origins, highlights a critical need for heightened understanding of the mechanisms by which bats maintain potentially zoonotic viruses at the population level and transmit these pathogens across species. We review mechanistic models, which test hypotheses of the transmission dynamics that underpin viral maintenance in bat systems. A search of the literature identified only twenty-five mechanistic models of bat-virus systems published to date, derived from twenty-three original studies. Most models focused on rabies and related lyssaviruses (eleven), followed by Ebola-like filoviruses (seven), Hendra and Nipah-like henipaviruses (five), and coronaviruses (two). The vast majority of studies has modelled bat virus transmission dynamics at the population level, though a few nested within-host models of viral pathogenesis in population-level frameworks, and one study focused on purely within-host dynamics. Population-level studies described bat virus systems from every continent but Antarctica, though most were concentrated in North America and Africa; indeed, only one simulation model with no associated data was derived from an Asian bat-virus system. In fact, of the twenty-five models identified, only ten population-level models were fitted to data – emphasizing an overall dearth of empirically derived epidemiological inference in bat virus systems. Within the data fitted subset, the vast majority of models were fitted to serological data only, highlighting extensive uncertainty in our understanding of the transmission status of a wild bat. Here, we discuss similarities and differences in the approach and findings of previously published bat virus models and make recommendations for improvement in future work.

Anatomy of bat genital organs has been conventionally studied by gross and microscopic observations to date. Here, we employ both histological observation and diceCT (diffusible iodine-based contrast-enhanced computed tomography) to study the detailed three-dimensional morphological structure of the male genital organs in bats, using the greater horseshoe bat, Rhinolophus ferrumequinum. This is the first study to three-dimensionally describe the whole reproductive organs of bats in detail. Our highly resolved three-dimensional reconstruction reveals that the male organs of R. ferrumequinum consist of paired testes, epididymides, deferent ducts, and five accessory genital glands. The boundary between the ampullary and vesicular glands has been difficult to identify in previous observations, but our diceCT imaging allowed us to clearly differentiate the two. We found that the ampullary gland is located at the terminal part of the deferent ducts, and the vesicular gland lies distal to the ampullary glands. This species possesses a single and carrot-shaped urethral gland, which is not found in most chiropteran families. The presence of the urethral gland in this species and its secretions suggest that after copulation this species is capable of forming a vaginal plug, which can seal the female’s vaginal orifice to block the entrance of spermatozoa from other males. The presence of the urethral gland and elongated epididymal tail and the fact that some individuals can terminate their hibernation and reactivate imply forced copulation on hibernating females can occur in R. ferrumequinum.

Polyomaviruses (PyVs) are small, circular dsDNA viruses carried by diverse vertebrates, including bats. Although previous studies have reported several horseshoe bat PyVs collected in Zambia and China, it is still unclear how PyVs evolved in this group of widely dispersed mammals. Horseshoe bats (genus Rhinolophus) are distributed across the Old World and are natural reservoirs of numerous pathogenic viruses. Herein, non-invasive bat samples from European horseshoe bat species were collected in Hungary for PyV identification and novel PyVs with complete genomes were successfully recovered from two different European horseshoe bat species. Genomic and phylogenetic analysis of the Hungarian horseshoe bat PyVs supported their classification into the genera Alphapolyomavirus and Betapolyomavirus. Notably, despite the significant geographical distances between the corresponding sampling locations, Hungarian PyVs exhibited high genetic relatedness with previously described Zambian and Chinese horseshoe bat PyVs, and phylogenetically clustered with these viruses in each PyV genus. Correlation and virus–host relationship analysis suggested that these PyVs co-diverged with their European, African and Asian horseshoe bat hosts distributed on different continents during their evolutionary history. Additionally, assessment of selective pressures over the major capsid protein (VP1) of horseshoe bat PyVs showed sites under positive selection located in motifs exposed to the exterior of the capsid. In summary, our findings revealed a pattern of stable intrahost divergence of horseshoe bat PyVs with their mammalian hosts on the African and Eurasian continents over evolutionary time.

The molossid bat Tadarida brasiliensis has a wide and apparently continuous distribution in South America. Although it has been reported in several localities of both versants of the Peruvian Andes, the potential distribution for this species has not been formally analyzed. Therefore, we describe its distributional pattern in the territory and provide comments about the possible influence of the Andes in its distribution. We gathered occurrence records from museums, acoustic surveys, literature, GBIF and Vertnet sources, and we selected localities to minimize spatial correlation. After defining a minimum-convex polygon of Peruvian records as background area, we use Maxent software with bioclimatic variables to construct species distribution models. Several models were evaluated using different metrics, and the model with the lowest AICc was selected. Then, the model was projected for Peruvian territory. Tadarida brasiliensis is reported for the first time in Cajamarca, Piura and Ica departments. The potential distribution model showed two disjunct suitable areas, one for the Pacific versant and other for the Amazonian versant of the Andes, but connected with moderate suitable conditions in the Huancabamba Depression region in northern Peru. Mean diurnal range and annual mean temperature were identified as the main limiting factors for the potential distribution of this species in this territory. Tadarida brasiliensis exhibits a discontinuous distribution in the Peruvian territory. In northern part, the Huancabamba depression zone has climatic conditions that may allow the east-west dispersal for this species. In central and southern parts, the higher crest of the Andes (> 4,500 m) has low suitable conditions due to the extreme climate. In the eastern, the lowland Amazonian forests has low suitability for this species, probably due to high temperatures. We suggest that the Andes could be acting a biogeographical barrier that limits the dispersal for this species, but population-genetic studies are needed to confirm this hypothesis. We identified that temperature is the main climatic factor that limit the dispersal of this bat. In conclusion, T. brasiliensis is mainly associated with desert and Andean slopes ecosystems in Peru, and we highlight the importance of incorporating acoustic records in the analysis of its distribution patterns.

Moonlight intensity influences the activity patterns of bats. Some bat species reduce their activity levels during brighter nights, a phenomenon known as “lunar phobia.” While lunar phobia of bats has been extensively studied in tropical regions, the same is not the case of bats in temperate regions. By using acoustic detectors, we examined differences in the activity of insectivorous bats on nights with different moonlight intensity in an agricultural landscape of central Chile. We also examined the hourly activity patterns throughout the night and how these varied between full and new moon nights. All bat species modified their activity based on the moonlight intensity; however, their effects were species-specific. The activity of Lasiurus varius, L. villosissimus, Myotis chiloensis, and Histiotus montanus was lower during bright nights, while Tadarida brasiliensis was the only species whose activity was higher during bright nights. Hourly activity throughout the night differed between full moon nights and new moon nights in most bat species. During full moon, bats concentrated their activities in the early hours of the nights; a more homogeneous activity pattern was exhibited during new moon night. Our study demonstrates that moonlight affects the activity of bats in Chile, a factor that should be considered when studying bats.

Renewable energy sources, such as wind energy, are essential tools for reducing the causes of climate change, but wind turbines can pose a collision risk for bats. To date, the population‐level effects of wind‐related mortality have been estimated for only 1 bat species. To estimate temporal trends in bat abundance, we considered wind turbines as opportunistic sampling tools for flying bats (analogous to fishing nets), where catch per unit effort (carcass abundance per monitored turbine) is a proxy for aerial abundance of bats, after accounting for seasonal variation in activity. We used a large, standardized data set of records of bat carcasses from 594 turbines in southern Ontario, Canada, and corrected these data to account for surveyor efficiency and scavenger removal. We used Bayesian hierarchical models to estimate temporal trends in aerial abundance of bats and to explore the effect of spatial factors, including landscape features associated with bat habitat (e.g., wetlands, croplands, and forested lands), on the number of mortalities for each species. The models showed a rapid decline in the abundance of 4 species in our study area; declines in capture of carcasses over 7 years ranged from 65% (big brown bat [Eptesicus fuscus]) to 91% (silver‐haired bat [Lasionycteris noctivagans]). Estimated declines were independent of the effects of mitigation (increasing wind speed at which turbines begin to generate electricity from 3.5 to 5.5 m/s), which significantly reduced but did not eliminate bat mortality. Late‐summer mortality of hoary (Lasiurus cinereus), eastern red (Lasiurus borealis), and silver‐haired bats was predicted by woodlot cover, and mortality of big brown bats decreased with increasing elevation. These landscape predictors of bat mortality can inform the siting of future wind energy operations. Our most important result is the apparent decline in abundance of four common species of bat in the airspace, which requires further investigation., Article impact statement: Data from 594 wind turbines suggest rapid declines in abundance for 4 common species of bat and identify spatial predictors of bat mortality at turbines.

A range of silvicultural treatments are applied to timber production forests, resulting in varied vegetation structural complexity. We compared the bat assemblage across three silvicultural treatments (unlogged forest, unthinned regrowth and thinned regrowth), two locations (on and off track) and three time periods (pre-thin, plus one and six years post-thinning) in wet sclerophyll forests, with treatments implemented at a small catchment scale. Linear edges provided important habitat for bats as total bat activity was substantially greater on tracks than off tracks, especially in unlogged and unthinned regrowth forest. Bat activity off track was greater in unlogged areas than in thinned and unthinned regrowth. Activity and species richness off track were greater in thinned than unthinned regrowth, but the time by treatment interaction was not significant for activity, indicating this difference cannot be ascribed to thinning alone. Thinning also led to a species composition that more closely resembled unlogged forest than unthinned regrowth. These patterns in bat activity across silvicultural treatments in wet sclerophyll forests were broadly consistent with other forest types, but subtleties, such as a subdued response to thinning, requires more replication to resolve. Nevertheless, differences between forest types need to be considered when developing management strategies.

A large number of bat fatalities have been reported in wind energy facilities in different regions globally. Wind farm operators are required to monitor bat fatalities by conducting carcass surveys at wind farms. A previous study implemented the ballistics model to characterize the carcass fall zone distributions after a bat is struck by turbine blades. The ballistics model considers the aerodynamic drag force term, which is dependent upon the carcass drag coefficient. The bat carcass drag coefficient is highly uncertain; no measurement of it is available. This paper introduces a methodology for bat carcass drag coefficient estimation. Field investigation at Macksburg wind farm resulted in the discovery of three bat species: the hoary bat (Lasiurus cinereus), eastern red bat (Lasiurus borealis), and evening bat (Nycticeius humeralis). Carcass drop experiments were performed from a dropping platform at finite height, and carcass position time series data were recorded using a high-speed camera. Falling carcasses were subjected to aerodynamic drag and gravitational forces. Carcasses were observed to undergo rotation, often rotating around multiple axes simultaneously, as well as lateral translation. The complex fall dynamics, along with drop from a limited height, prohibit the carcasses from attaining terminal velocity. Under this limitation, the drag coefficient is estimated by fitting a ballistics model to the measured velocity. Multivariable optimization was performed to fit the ballistics model to the measured velocity resulting, in an optimized estimate of the drag coefficient. A sensitivity analysis demonstrated significant variation in the drag coefficient with a small change in initial position, highlighting the chaotic nature of carcass fall dynamics. Based on the limited sample, the bat carcass drag coefficient and terminal velocity were found to be between 0.70–1.23 and 6.63–17.57 m s−1, respectively. The maximum distance carcasses are predicted to fall after impact with a typical utility-scale onshore wind turbine was computed using a 2-D ballistics model. Based on the range of drag coefficients found in this study, hoary and evening bats are estimated to fall within the rotor plane up to a maximum distance of 92 and 62 m, respectively, from the wind turbine tower. The ballistics model of carcasses after being struck by wind turbine blades can be used to obtain fall distributions for bats, guide carcass survey efforts, and correct survey data for limited or unsearched areas.

Bats are potential natural hosts of Encephalomyocarditis virus (EMCV) and Japanese encephalitis virus (JEV). Bats appear to have some unique features in their innate immune system that inhibit viral replication causing limited clinical symptoms, and thus, contributing to the virus spill over to humans. Here, kidney epithelial cell lines derived from four bat species (Pteropus dasymallus, Rousettus leschenaultii, Rhinolophus ferrumequinum, and Miniopterus fuliginosus) and two non-bat species (Homo sapiens and Mesocricetus auratus) were infected with EMCV and JEV. The replication of EMCV and JEV was lower in the bat cell lines derived from R. leschenaultii, R. ferrumequinum, and M. fuliginosus with a higher expression level of pattern recognition receptors (PRRs) (TLR3, RIG-I, and MDA5) and interferon-beta (IFN-β) than that in the non-bat cell lines and a bat cell line derived from P. dasymallus. The knockdown of TLR3, RIG-I, and MDA5 in Rhinolophus bat cell line using antisense RNA oligonucleotide led to decrease IFN-β expression and increased viral replication. These results suggest that TLR3, RIG-I, and MDA5 are important for antiviral response against EMCV and JEV in Rhinolophus bats., Highlights • Some bat cell lines showed a limited cytopathic effect after EMCV and JEV infection. • EMCV and JEV replication was inhibited in some bat cell lines. • Expression of PRRs and IFN-β was highly induced in some bat cell lines. • PRRs and IFN-β contributed to antiviral response against EMCV and JEV in bats.