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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. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

An astonishing number of bat fatalities (2,371 belonging to 15 species) were recovered in a provincial surveillance program at wind farms in Cádiz, at the southern tip of Spain, in 2005–2016. We carefully analysed a subset of this sample intending to estimate the true fatality rate in the year 2011, the year for which we had the richest data set (582 fatalities at 38 wind farms). To estimate the true fatality rate, we conducted search-efficiency and scavenger-removal trials in nine wind farms involving 122 turbines and 289 observed fatalities and calculated the searchable surface. An annual fatality rate of 41.1 dead bats per turbine (26.4 per MW) was estimated in the study area using a self-developed estimator due to the singularities of the surveillance program. Our estimator results are lower than those obtained using the Generalized Mortality Estimator (GenEst) developed by U.S. Geological Survey. Estimates of 37,689 or 33,370 fatalities were made according to the province's number of turbines or MW in 2011. Some areas have registered the highest fatality rates ever recorded for bats in wind turbines anywhere globally, even more so because we have been conservative. There is an urgent need for efficient preventive and mitigation measures at wind farms in risky landscapes and with a high rate of bat fatalities, but trials are also needed to know how well the post-operational monitoring is done and how far it is from reality. Clearly, current official post-construction surveillance programs are inefficient for searching bats and therefore mask a high fatality rate, mainly of sedentary bats. [ABSTRACT FROM AUTHOR]

Paraguay lies in an area of transition between the tropics and subtropics, and encompasses the interface of six South American ecoregions. Because of its central location within the climatic and biotic schema of the South American continent, Paraguay is ideal for exploring a variety of biogeographic and ecological questions. Several studies have evaluated the taxonomic, biogeographic and migratory status of the 59 species of bats currently recognized in Paraguay, and other studies have evaluated aspects of population genetics and community ecology of frugivorous bats in eastern Paraguayan forests. However, no study has evaluated the environmental factors influencing bat community structure within the mosaic of savanna ecoregions which extend over a majority of the Paraguayan territory. Based on conservative selection criteria, six bat communities from the Cerrado, Humid Chaco and Dry Chaco were evaluated in this study. Climatic data included a suite of temperature and precipitation parameters for each site. Latitude and longitude were also included as factors potentially predicting bat community parameters. Gini-Simpson diversity indices were calculated for each site, separately for species diversity, taxonomic diversity and trophic diversity. Environmental variables were evaluated for their associations with each of the three diversity indices. Significant differences were found among the six sites based on each of the three diversity indices. In general, precipitation variables are more influential than temperature variables in determining bat community diversity levels in Paraguayan savanna ecosystems. Species diversity can best be predicted with a linear combination of mean annual precipitation and mean precipitation of the driest month. Taxonomic diversity is best predicted using mean annual precipitation alone. In contrast, best prediction of trophic diversity is with mean precipitation of driest month. Species and taxonomic diversity patterns were generally concordant for the Cerrado and Humid Chaco communities, whereas trophic diversity was inconsistent among the Humid Chaco communities. An analysis of variance combining the three diversity indices, showed three non-significantly different groups of communities: (1) the two Dry Chaco communities; (2) a Dry Chaco and a Humid Chaco community; and (3) the Cerrado and three Humid Chaco localities. These results should be considered in bat conservation management strategies, which should incorporate benchmarks not only of species diversity, but also of taxonomic and trophic diversity. Paraguay se encuentra en un área de transición entre los trópicos y subtrópicos, abarcando una interfaz de seis ecorregiones sudamericanas. Por su ubicación central a nivel climático y biótico del continente sudamericano, es ideal para presentar diferentes preguntas biogeográficas y ecológicas. Varios estudios han evaluado el estado taxonómico, biogeográfico y migratorio de las 59 especies de murciélagos actualmente registradas, otros han evaluado aspectos de genética poblacional y ecología de comunidades de murciélagos frugívoros en los bosques del este de Paraguay, pero ninguno ha evaluado los factores ambientales que influyen en la estructura de la comunidad dentro del mosaico de ecorregiones de sabana que se extienden sobre gran parte del territorio. Se evaluaron seis comunidades de murciélagos, considerando criterios conservadores de selección. Los datos climáticos incluyeron parámetros de temperatura y precipitación para cada sitio. La latitud y la longitud se incluyen como potenciales factores para predecir parámetros de la comunidad. Se calcularon por separado, índices de diversidad de Gini-Simpson para cada sitio, para diversidad de especies, diversidad taxonómica y diversidad trófica. Así también, variables ambientales fueron evaluadas y asociadas con cada índice de diversidad. Se registraron diferencias significativas entre los seis sitios con respecto a los tres índices de diversidad. Las variables de precipitación influyen más que las de temperatura para determinar los niveles de diversidad de la comunidad en ecosistemas de sabana. La diversidad de especies fue determinada utilizando la combinación lineal de precipitación media anual y precipitación media del mes más seco. La diversidad taxonómica se predice mejor utilizando únicamente la precipitación media anual. La predicción de la diversidad trófica es más compleja, ya que combina la precipitación media anual, error estándar de precipitación media anual, precipitación media del mes más seco y rango de temperatura diurna media. Los patrones de diversidad taxonómica y de especies fueron semejantes para comunidades del Cerrado y Chaco Húmedo, mientras que la diversidad trófica fue inconsistente entre comunidades del Chaco Húmedo. El análisis de la varianza de los tres índices de diversidad juntos, mostró que tres grupos de comunidades no presentaron diferencias significativas: las dos comunidades del Chaco Seco; una del Chaco Seco y una del Chaco Húmedo; la del Cerrado y tres localidades del Chaco Húmedo. Estos resultados deben ser considerados para estrategias de manejo de conservación, incorporando puntos de referencia no solo de diversidad de especies, sino también de diversidad taxonómica y diversidad trófica. [ABSTRACT FROM AUTHOR]

The tricolored bat (Perimyotis subflavus) has experienced extensive declines in regional abundance — near 30% as of 2013 — due to disease, habitat loss, and anthropogenic conflict. There is urgency to determine whether the species should be protected in the United States; however, critical species-specific information required to make this decision is lacking. Here, we address those critical knowledge gaps by (i) estimating genetic diversity, and (ii) assessing population structure. We utilized sequence data from a 562 base pair region of the mitochondrial genome and eight autosomal microsatellite loci from 14 sampling locations across the core of P. subflavus' range and found substantial diversity in both data types. Further, we found contrasting patterns of population structure between the data types. Weak evidence for population structure was detected using the mitochondrial data, with the most probable population break dividing eastern and western sampling sites, and evidence for isolation-by-distance across the sampled region. Conversely, we detected no evidence for structure or isolation-by-distance using microsatellite data, revealing a panmictic population. The findings reported here represent a baseline understanding of genetic diversity and structure for P. subflavus; additional analyses using samples collected post white-nose syndrome emergence are required to understand losses in genetic diversity due to recent population declines. [ABSTRACT FROM AUTHOR]

Spatio-temporal patterns of species richness, Hill numbers, captures per species, feeding guilds, sex ratio, and biomass were studied in a Neotropical bat assemblage during 17 continuous months in four bands (low: 50–150, mid-low: 375–500, mid-high: 975–1,050, and high: 1,950–2,050 m a.s.l.) in an elevational gradient in Costa Rica. We found an effect of elevation on species richness. As expected, species richness was high in the low elevations; unexpectedly, however, we noted that species richness was highest in the mid-high band, a diversity pattern that has not been previously recorded in bats. We also found an effect of precipitation periods on species richness; in particular, at mid-high elevations, when precipitation was intermediate and highest, we observed a larger number of species. When analyzing data separately by feeding ensemble, we found an effect of elevation on species richness for three ensembles: animalivorous bats were more diverse at the mid-low band, nectarivorous bats were more diverse in the mid-high and high bands, and frugivorous bats were more diverse in the mid-low and low bands. Species richness of frugivorous bats was also affected by precipitation; when rainfall was intermediate and highest, we noted a higher species richness of this ensemble. There was no effect of elevation on species richness for the insectivorous, omnivorous or hematophagous ensemble, nor on the species capture, sex ratio or biomass. Our results not only provide further evidence of the importance of lowland forests as reservoirs of high species diversity, but also highlight the importance of tropical premontane rainforests for the conservation of bat communities given their high species richness, particularly for the nectarivorous and frugivorous ensembles. This is particularly relevant not only because this ecosystem has been heavily affected by land use changes in the Neotropical region, but also because the predicted future decrease of precipitation at this elevation could potentially affect overall species richness and particularly for certain feeding ensembles. Thus, conservation efforts in this life zone are of critical importance for maintaining functional and ecological diversity of bat communities in elevational gradients. [ABSTRACT FROM AUTHOR]

We present the result of bat winter censuses in three old mines in southern Sweden from 1980 until present (2017). The Taberg and Kleva mines, each with about 1.5 km of accessible passages, have winter populations of 517 and 132 bats, respectively (maximum counts) belonging to six species, the highest numbers known in underground sites in Sweden. Ädelfors is less extensive and has fewer individuals (maximum 22). The two former sites were protected and gated in the 1980′s while the third site still has no formal protection and is subject to disturbance. Generally Daubenton's bat Myotis daubentonii and the brown long-eared bat Plecotus auritus are common species and the numbers are stable. The whiskered and Brandt's bats M. mystacinus/brandtii and Natterer's bat M. nattereri have increased significantly, while the northern bat Eptesicus nilssonii, which is relatively rare in mines generally, has shown a slight but significant decline. At the species level the population trends conform well to those of the respective species in continental Europe and the British Isles. This suggests that there is a common factor behind the population changes across Europe. Although our data are very limited, the results question some previous explanations for the observed trends, but are in line with theoretical predictions based on global warming scenarios. [ABSTRACT FROM AUTHOR]

Lactation is one of the most energetically demanding periods in the life cycle of a small mammal. Classified as income breeders, hibernating small colonial insectivorous bats are hypothesised to compensate for the energetic demand of lactation by increasing daily food intake, which increases body mass. The Natal long-fingered bat Miniopterus natalensis is a colonial hibernating species in southern Africa for which energy compensation was hitherto unknown. We tested predictions of the energy compensation hypothesis using a wild population of M. natalensis during the parturition and maternity period of November–December in 2015–2017. The study was conducted at the Meletse Bat Research and Conservation Training Centre near Gatkop Cave, in Limpopo Province, South Africa. We weighed and categorised 2,707 M. natalensis females captured during evenings and mornings into one of four groups including not pregnant with a sclerotized nipple (NP-SC), not pregnant with a non-sclerotized nipple (NP-NSC), lactating with a sclerotized nipple (L-SC), and pregnant with a sclerotized nipple (P-SC). NP-NSC and NP-SC females were classified as non-reproductive, whilst L-SC and P-SC females were classified as active breeders. Results showed that females in the L-SC category were 6% heavier than females in non-reproductive categories (NP-NSC and NP-SC). Pregnant females were 25% heavier than non-reproductive females due, at least in part, to foetus mass, whilst the mean body mass did not differ between females in non-reproductive categories. Whilst the body mass of females in the NP-NSC, NP-SC and L-SC categories did not differ during evening captures, L-SC females showed the biggest mass increase between evening and morning captures. Proportions of females captured from reproductive categories differed among years, with a higher overall proportion of active breeders (70%) in 2017 than either 2016 (33%) or 2015 (31%). This may be related to inter-annual variation in climate and warrants further investigation. Our results suggest female M. natalensis were heavier, on average, during lactation and support the energy compensation hypothesis. [ABSTRACT FROM AUTHOR]