The vespertilionid bat genus Hesperoptenus, comprising only five species and showing a distribution in the tropical regions from India to Sulawesi, was hitherto underrepresented in recent taxonomic studies. Here, modern cytogenetic techniques were applied to compare the karyotypes of two Hesperoptenus species, H. tomesi and H. blanfordi. Despite having the same chromosome number, 2n = 32, the karyotypes of H. tomesi and H. blanfordi were found to differ extensively. Instead, H. tomesi was found to share all nine derived Robertsonian fusion products with the previously published karyotype of H. doriae (2n = 26), which points to a closer relationship between both species. In line with our chromosomal data, mitochondrial DNA analyses also provided evidence for a closer relationship of H. tomesi with H. doriae and H. tickelli, for which no banded karyotype has been examined. Again, H. blanfordi was clearly separated from the remaining Hesperoptenus species. As a consequence, the subgenus Milithronycteris, comprising all species of Hesperoptenus except the type species H. doriae, is rendered paraphyletic. We therefore suggest to synonymize Milthronycteris with the subgenus Hesperoptenus. A chromosomal character, found in all three Hesperoptenus species examined but absent in other vespertilionid genera studied so far, namely a particular G-banding pattern on the homolog to Myotis chromosome MMY13, may serve as a synapomorphy for the genus Hesperoptenus.

Frugivory and seed dispersal are fundamental processes for biodiversity, especially in forest environments, which are increasingly fragmented and scarce. Bats are crucial seed dispersers due to the large number of species that feed on fruits, coupled with their wide dispersal ability through flight. We evaluated the bat-plant interaction network structure in forest areas of the Amazon, Cerrado, and the ecotonal region between these biomes. Using ecological network theory, we examined the contribution of species in structuring these networks and the main predictors of the roles bat species play. We captured bats in the field and collected seeds from fecal samples to identify plant species consumed in three landscape-scale environments. We built interaction networks for each environment, and evaluated the number of links, specialization, and modularity of each network. We also calculated species-level metrics to assess the contribution of bat and plant species to structuring the interaction networks. Finally, we tested the influence of bat mass, degree of frugivory, and abundance on their role in the networks. We identified 348 interactions and 177 links in the three networks, recording 21 bat species and 77 plant species. We found a higher number of links in the ecotone network, which is also the most modular network. Carollia brevicauda and C. perspicillata had highest species strength and centrality values among bat species in the three interaction networks. Cecropia obstusa and Piper sp07 exhibited the highest species strength metric among plant species. Bat abundance was the best predictor of the role played by bats in the frugivory networks. The low specialization of the Amazon network may be due to the plant dominance of some species. However, the ecotone areas had the highest plant species richness, emphasizing the importance of this landscape in the context of environmental functionality and conservation in the ecotone.

La frugivoría y la dispersión de semillas son procesos fundamentales para la biodiversidad, especialmente en ambientes forestales, cada vez más fragmentados y escasos. Los murciélagos son dispersores de semillas cruciales debido a la gran cantidad de especies que se alimentan de frutas, junto con su amplia capacidad de dispersión a través del vuelo. Evaluamos la estructura de la red de interacción murciélago-planta en áreas forestales del Amazonas, Cerrado y la región ecotonal entre estos biomas. Utilizando la teoría de redes ecológicas, examinamos la contribución de las especies en la estructuración de estas redes y los principales predictores del papel que desempeñan las especies de murciélagos. Capturamos murciélagos en el campo y recolectamos semillas de muestras fecales para identificar especies de plantas consumidas en tres ambientes a escala de paisaje. Construimos redes de interacción para cada entorno y evaluamos la cantidad de enlaces, especialización y modularidad de cada red. También calculamos métricas a nivel de especie para evaluar la contribución de las especies de murciélagos y plantas a la estructuración de las redes de interacción. Finalmente, probamos la influencia de la masa de los murciélagos, el grado de frugivoría y la abundancia en su papel en las redes. Identificamos 348 interacciones y 177 vínculos en las tres redes, registrando 21 especies de murciélagos y 77 especies de plantas. Encontramos un mayor número de enlaces en la red ecotone, que también es la red más modular. Carollia brevicauda y C. perspicillata tuvieron los valores más altos de fuerza y centralidad entre las especies de murciélagos en las tres redes de interacción. Cecropia obstusa y Piper sp07 exhibieron la métrica de fuerza de especie más alta entre las especies de plantas. La abundancia de murciélagos fue el mejor predictor del papel desempeñado por los murciélagos en las redes frugívoras. La baja especialización de la red amazónica puede deberse a la dominancia vegetal de algunas especies. Sin embargo, las áreas del ecotono tuvieron la mayor riqueza de especies vegetales, resaltando la importancia de este paisaje en el contexto de la funcionalidad y conservación ambiental en el ecotono.

We investigated the effect of anthropogenically-driven habitat modifications on insectivorous bat activity and diversity along a stretch of the Eerste River, Stellenbosch, South Africa, by determining insect abundance, water quality and vegetation and river characteristics at four sites of varying anthropogenic impact. Passive acoustic monitoring was used to determine species composition and activity of bats at each of the sites. A total of 14,457 bat passes was recorded, with the same six species being found at each of the sites: four clutter edge foragers (Myotis tricolor, Eptesicus hottentotus, Miniopterus natalensis and Laephotis capensis) and a single clutter forager (Rhinolophus clivosus) and open-air forager (Tadarida aegyptiaca). Bat activity was greater at the lower two most eutrophied sites, and greatest at the residential (urban) site. Laephotis capensis, an urban-adapted species, was by far the most active, probably on account of both insensitivity to light pollution, and roost-site availability. The highest and most pristine site (Eiland) and the lowest and most polluted site (Spier) displayed the greatest diversity, despite highly elevated levels of chloride and nitrate at the latter site. So anthropogenic effects on water quality appear not to have negatively affected bat diversity along this stretch of the Eerste River. As these effects are likely to increase, this study serves as a baseline for future monitoring of bats along its course.

Roads have a multitude of direct negative effects on wildlife due to collisions and noise and play a prominent role in overall habitat fragmentation. For bats, landscape fragmentation by roads causes disturbance during nocturnal movements and road kill negatively affects local abundance and bat population dynamics. Mitigation measures such as wildlife crossings (green bridges) are among the proposed improvements intended to reduce the fragmentation impact of roads for many taxa, but their efficiency has rarely been tested for bats. In this study, we performed a control-impact analysis to assess the efficiency of two structures on the number of bat crossings by assessing their collision risk using an acoustic flight path reconstruction (AFPR) approach. We obtained data for 458 crossings for six bat taxa that showed how the number of bat crossings is significantly higher on green bridges than control sites for all species (pooled) and for two guilds — one with species with a low flight height and the other with a higher flight height. We also found that bat activity on either side of a green bridge is not a predictor of the true use of the bridge to cross roads. Considering these results, wildlife crossings can be envisaged as a mitigation measure to reduce impacts of road construction on bat movements.

This study examines the impact of habitat management on the seasonal and spatial activities of bat species in Mediterranean scrublands of southern France. Three study sites, presenting managed and unmanaged scrublands, were sampled by acoustic recording to assess their ecological potential for bat conservation. General linear mixed models (GLMMs) were used to identify the key factors driving variation in activity patterns of these areas. A total of 16 bat species were recorded, and no significant differences in taxonomic composition were found between managed and unmanaged areas. Bats have an opportunistic tendency to explore different habitats over long distances. In addition to the strong seasonal dynamics observed in most species, we found evidence of a shift in activity rhythms suggesting species adaptation to seasonal thermal variations and prey availability. In this study, the impact of managed areas on activity patterns depends on the functional traits of each species. Level of activity differed considerably from one species to another, suggesting that the ‘management’ effect is not the only ecological parameter involved in conditioning bats’ preferred occupancy patterns.

Riparian ecosystems are valuable habitats for bats, due to high densities of emergent aquatic invertebrates that provide high-quality feeding areas. Throughout Europe, decline and extirpation of European beaver (Castor fiber) has been a key driver in the decline of the extent and quality of riparian habitat, and thus recolonisation has considerable potential to restore degraded areas. Previous research has shown that beaver-modified ecosystems can support more bats, but the assumed causal link (an increase in invertebrate prey) has not been tested. Here, we study bat activity and richness/abundance of aquatic macroinvertebrates at a site where free-roaming beavers have colonised naturally from a nearby (unofficial) release location versus a nearby control site with very similar hydrology and habitat matrix. Bat activity was recorded using walked activity transects and fixed-point acoustic detectors. Although bat species richness was similar, bat activity was substantially and significantly higher at the beaver site versus the control site overall (42.7%) and for four specific taxa: soprano pipistrelle (Pipistrellus pygmaeus; 8.4%), Daubenton's (Myotis daubentonii; 46.5%), common pipistrelle (Pipistrellus pipistrellus; 110.4%) and common noctule (Nyctalus noctula; 170.9%). Richness of the larvae/nymphs of emergent aquatic macroinvertebrate species known to form an important part of bat diet was 205.5% higher at the beaver site compared to the control site, while abundance was 817.4% higher. Overall bat activity was also linked to habitat (lotic > lentic), survey method (transect > fixed-point), and season (May–July peak). This is the first evidence of a likely causal link between beaver recolonisation and bat activity via an increase in abundance of key aquatic invertebrate prey and we recommended that benefits of beaver reintroduction on bats be considered in future feasibility studies.

Integrated air temperature between January 1 and March 31 was recorded from 1983 to 2023 near a nursery roost of Pipistrellus pygmaeus in West Wales, U.K. Integrated air temperature was defined as accumulated heat above a threshold temperature above 5°C when Chironomid prey flew. Between 2003–2023 integrated air temperatures were in the same range (71–264 degree days) as those from 1983 to 2002 but the incidence of warm years increased. There were eight years from 2003–2023 when records were > 203 degree days compared with four years from 1983–2002. The effect on P. pygmaeus was investigated and weekly exit records from April 1 to September 27 during 1983–2002 showed six years when the first peak exit count in May–June (N_JN) occurred earlier than anticipated (weeks 6–8, April 1 = week 1) so N_JN counts were not within the U.K. national monitoring period (weeks 9–12). Subsequently, the probability of early N_JN counts in weeks 6–8, based on the changes in the integrated air temperature January to March, was calculated. A binary logistic model predicted that for 95% of the time, the likelihood of an earlier peak exit count in six to eight weeks exceeded 1.0 (OR = 1.06, 95% CI = 1.02–1.10) for every one degree day of increase in the integrated air temperature. The probability of an early peak exit count in weeks 6 to 8 stabilized to 0.80 to 0.95, when the integrated air temperature increased linearly from 210 to 264 degree days. The annual integrated air temperatures from January to March at 66.7% of 24 nursery roost sites in the U.K. from 2019–2023 ranged from 150–259 degree days, so prediction of early peak exit events could optimize nursery roost counts by addition of counts in weeks 6–8 at selected maternity roosts when the annual integrated air temperature ranged from 210–264 degree days and enable assessment of the extent and pace of climate change on P. pygmaeus.

The hairy-legged vampire bat, Diphylla ecaudata, is a relatively rare, poorly known, and specialized species that feeds primarily on the blood of birds. We studied a large colony of D. ecaudata rosting with the common hematophagous bats Desmodus rotundus, in a brick house in São Paulo, a large metropolis in southeastern Brazil. The colony size varied from 68 individuals in July 2011 to 21 in February 2014, and females were slightly larger than males. This is the first record of a large group of D. ecaudata sheltering in a man-made structure in Brazil and the first largest group of the species recorded in the country. As a rabies control measure, some animals were subjected to fluorescent antibody and mouse inoculation tests. Blood samples were collected from 24 animals, and the sera were tested for the presence of rabies antibodies using a simplified fluorescent inhibition microtest. No bat tested positive for rabies. Using 0.5 IU/ml as the cut-off, the prevalence of rabies antibodies was 58.8% in D. ecaudata and 83.0% in D. rotundus. The expressive levels of rabies antibodies indicate that the rabies virus actively circulates between the two species.

El murciélago vampiro patas peludas, Diphylla ecaudata, es una especie especializada, relativamente rara y poco conocida, que se alimenta principalmente de sangre de aves. Estudiamos una gran colonia de D. ecaudata cohabitando con el murciélago vampiro común Desmodus rotundus en una casa de ladrillos en la ciudad de São Paulo, una gran metrópolis en el sureste de Brasil. El tamaño de la colonia varió de 68 individuos en julio de 2011 a 21 en febrero de 2014, y las hembras fueron ligeramente más numerosas que los machos. Este es el primer registro de un grupo grande de D. ecaudata ocupando una estructura artificial en Brasil y el primer registro de un grupo tan grande de la especie en el país. Como medida de control de la rabia, algunos animales fueron sometidos a pruebas de anticuerpos fluorescentes y de inoculación utilizadas en ratones. Se recolectaron muestras de sangre de 24 animales y los sueros se analizaron para detectar la presencia de anticuerpos contra la rabia mediante una microprueba de inhibición fluorescente simplificada. Ningún murciélago dio positivo por rabia. Utilizando 0,5 UI/ml como punto de corte, la prevalencia de anticuerpos contra la rabia fue del 58,8% en D. ecaudata y del 83,0% en D. rotundus. Los niveles de expresión de anticuerpos contra la rabia indican que el virus de la rabia circula activamente entre las dos especies.

To date, 55 species of bats have been recorded over a wide range of altitudes from 64 to 4,154 m above sea level (a.s.l.) in Nepal. One third of Nepal, including eight protected areas, most of the Higher Mountain region and the western part of the country, has yet to be surveyed. In this study, mist netting, harp trapping, roost and acoustic surveys revealed a total of 34 species of bats belonging to 22 genera from nine districts of Nepal. Coelops frithii and Harpiocephalus harpia were noted for the first time from the country. Bats were recorded at altitudes from 240 to 3,232 m, with 25 species recorded from middle elevation ranges (1,001–2,000 m a.s.l.), 21 species from higher elevation ranges (2,001–3,232 m a.s.l.), and 20 species from lower elevation ranges (240–1,000 m a.s.l.). The distribution patterns across different ranges were species-specific (e.g., irregular in Myotis csorbai, hump-shaped in Submyotodon caliginosus, and linear in Nyctalus noctula), with high species richness observed at elevations from 501 to 1,000 m a.s.l. (22 species), followed by 1,001–1,500 m a.s.l. (21 species). These data are expected to guide the designation of new survey and monitoring areas in the future. Consequently, further detailed surveys and monitoring, particularly in western Nepal and the Higher Mountain regions, are likely to yield new distribution records of bats, both nationally and globally.

Covariation patterns of dental traits vary greatly among mammals due to the effect of evolutionary factors. Studies of integration and modularity in dentition in closely related species could provide insights into evolutionary patterns at higher taxonomic levels. We studied the initial stage of trait divergence using two subspecies of closely related bat species, Myotis myotis myotis and M. blythii oxygnathus (family Vespertilionidae), utilizing a collection of 105 specimens from Ukraine and 63 paired quantitative characters. We identified modularities in the dentitions. For vestigial teeth, we found decreased correlations with other teeth and increased variation. The overall modularity of odontometric characters was slightly higher in M. b. oxygnathus. The internal constraints on evolutionary change were unexpectedly high. Variation and covariation in tooth sizes were critically limited in the studied Myotis species, which could be attributed to the need to maintain accurate occlusion. Using the example of M. myotis and M. blythii dentition, we observe the initial stage of the divergence in a highly canalized structure.

Measurement of bat guano deposition rate in caves can be an important research tool for estimation of colony size, for monitoring the record of long-term bat population trends, and for allied studies of guano invertebrate ecology, environmental contaminants, and paleoecology. However, previously published methodologies have lacked consistency. In the context of our recent studies of insectivorous bat guano deposition rates in Deer Cave, Sarawak, Borneo, we review some past studies and offer suggestions for best practises, along with proposed experimental design considerations for future studies (e.g., design of guano catchers, optimum deployment of catchers in relation to specific site characteristics, data reporting standards, and examples of mapping techniques). Consistent techniques will facilitate inter-site comparisons, and determination of intra-site changes over time. As a case study, and the first publication of detailed mapping of spatial variability in guano deposition rates, we present spatially explicit guano deposition rates for Deer Cave, ranging up to 88 g (dry weight)/m²/day in the main cave, and up to 540 g (dry weight)/m²/day in the northern extension.