Insectivorous Bats Research Articles

Functional diversity and trait filtering of insectivorous bats relate to forest biogeography and fragmentation in South Africa

AbstractAimForest fragmentation is a major driver of biodiversity loss causing declines in species richness and functional diversity of biotic communities. Bats are essential components of ecosystems and are useful bio‐indicators of habitat disturbance, yet the response and vulnerability of bats to fragmentation have been poorly studied in Africa. We aim to assess the effects of forest biogeographical history and fragmentation on functional diversity of bats and their functional traits.LocationEastern Cape and southern KwaZulu‐Natal, South Africa.TaxonInsectivorous bats.MethodsWe surveyed forest‐utilizing bats to derive four functional diversity indices. Generalized linear models were used to assess the response of diversity indices to biogeographical history and fragmentation, represented by forest type and five landscape fragmentation metrics. RLQ and fourth‐corner analysis were used to investigate the interaction of traits with fragmentation metrics and forest type.ResultsPondoland Scarp forests displayed high functional richness, while Eastern Cape Dune forests exhibited high functional divergence yet low functional richness and dispersion. Two fragmentation metrics affected functional diversity dynamically: edge density had a positive effect on functional evenness; and dispersion was negatively affected by river length through forests. Results showed stronger interactions of functional traits with forest type than fragmentation metrics, with filtering effects on body size and wing morphology.Main conclusionsThe large‐scale processes related to biogeographical history, and associated forest structure, are important determinants of functional richness, divergence and dispersion of insectivorous bat communities. Scarp forests showed the highest species and functional richness as they experienced less extreme climatic extinction filtering than Mistbelt forests during the Last Glacial Maximum, whereas the low diversity of Eastern Cape Dune forests results from their younger evolutionary history and homogenous vegetation structure. Little is known of the sensitivity of bats to habitat fragmentation in Africa: here, we show larger‐sized insectivorous species; and species exhibiting low wing loading may be more vulnerable to fragmentation.

Insectivorous bats are less active near freeways.

Traffic disturbances (i.e. pollution, light, noise, and vibrations) often extend into the area surrounding a road creating a ‘road-effect zone’. Habitat within the road-effect zone is degraded or, in severe cases, completely unsuitable for wildlife, resulting in indirect habitat loss. This can have a disproportionate impact on wildlife in highly modified landscapes, where remaining habitat is scarce or occurs predominantly along roadside reserves. In this study, we investigated the road-effect zone for insectivorous bats in highly cleared agricultural landscapes by quantifying the change in call activity with proximity to three major freeways. The activity of seven out of 10 species of bat significantly decreased with proximity to the freeway. We defined the road-effect zone to be the proximity at which call activity declined by at least 20% relative to the maximum detected activity. The overall road-effect zone for bats in this region was 307 m, varying between 123 and 890 m for individual species. Given that this road-effect zone exceeds the typical width of the roadside verges (<50 m), it is possible that much of the vegetation adjacent to freeways in this and similar landscapes provides low-quality habitat for bats. Without accounting for the road-effect zone, the amount of habitat lost or degraded due to roads is underestimated, potentially resulting in the loss of wildlife, ecosystem services and key ecosystem processes (e.g. predator-prey or plant-pollinator interactions) from the landscape. We suggest all future environmental impact assessments include quantifying the road-effect zone for sensitive wildlife, in order to best plan and mitigate the impact of roads on the environment. Mitigating the effects of new and existing roads on wildlife is essential to ensure enough high-quality habitat persists to maintain wildlife populations.

Sampling flying bats with thermal and near-infrared imaging and ultrasound recording: hardware and workflow for bat point counts.

Bat communities can usually only be comprehensively monitored by combining ultrasound recording and trapping techniques. Here, we propose bat point counts, a novel, single method to sample all flying bats. We designed a sampling rig that combines a thermal scope to detect flying bats and their flight patterns, an ultrasound recorder to identify echolocating bat calls, and a near-infrared camera and LED illuminator to photograph bat morphology. We evaluated the usefulness of the flight pattern information, echolocation call recordings, and near-infrared photographs produced by our sampling rig to determine a workflow to process these heterogenous data types. We present a conservative workflow to enable taxonomic discrimination and identification of bat detections. Our sampling rig and workflow allowed us to detect both echolocating and non-echolocating bats and we could assign 84% of the detections to a guild. Subsequent identification can be carried out with established methods such as identification keys and call libraries, based on the visible morphological features and echolocation calls. Currently, a higher near-infrared picture quality is required to resolve more detailed diagnostic morphology, but there is considerable potential to extract more information with higher-intensity illumination. This is the first proof-of-concept for bat point counts, a method that can passively sample all flying bats in their natural environment.

Embryonic evidence uncovers convergent origins of laryngeal echolocation in bats

Bats are the second-most speciose group of mammals, comprising 20% of species diversity today. Their global explosion, representing one of the greatest adaptive radiations in mammalian history, is largely attributed to their ability of laryngeal echolocation and powered flight, which enabled them to conquer the night sky, a vast and hitherto unoccupied ecological niche. While there is consensus that powered flight evolved only once in the lineage, whether laryngeal echolocation has a single origin in bats or evolved multiple times independently remains disputed. Here, we present developmental evidence in support of laryngeal echolocation having multiple origins in bats. This is consistent with a non-echolocating bat ancestor and independent gain of echolocation in Yinpterochiroptera and Yangochiroptera, as well as the gain of primitive echolocation in the bat ancestor, followed by convergent evolution of laryngeal echolocation in Yinpterochiroptera and Yangochiroptera, with loss of primitive echolocation in pteropodids. Our comparative embryological investigations found that there is no developmental difference in the hearing apparatus between non-laryngeal echolocating bats (pteropodids) and terrestrial non-bat mammals. In contrast, the echolocation system is developed heterotopically and heterochronically in the two phylogenetically distant laryngeal echolocating bats (rhinolophoids and yangochiropterans), providing the first embryological evidence that the echolocation system evolved independently in these bats.

Prey removal in cotton crops next to woodland reveals periodic diurnal and nocturnal invertebrate predation gradients from the crop edge\xa0by birds and bats

Factors influencing the efficacy of insectivorous vertebrates in providing natural pest control services inside crops at increasing distances from the crop edge are poorly understood. We investigated the identity of vertebrate predators (birds and bats) and removal of sentinel prey (mealworms and beetles) from experimental feeding trays in cotton crops using prey removal trials, camera traps and observations. More prey was removed during the day than at night, but prey removal was variable at the crop edge and dependent on the month (reflecting crop growth and cover) and time of day. Overall, the predation of mealworms and beetles was 1-times and 13-times greater during the day than night, respectively, with predation on mealworms 3–5 times greater during the day than night at the crop edge compared to 95 m inside the crop. Camera traps identified many insectivorous birds and bats over crops near the feeding trays, but there was no evidence of bats or small passerines removing experimental prey. A predation gradient from the crop edge was evident, but only in some months. This corresponded to the foraging preferences of open-space generalist predators (magpies) in low crop cover versus the shrubby habitat preferred by small passerines, likely facilitating foraging away from the crop edge later in the season. Our results are in line with Optimal Foraging Theory and suggest that predators trade-off foraging behaviour with predation risk at different distances from the crop edge and levels of crop cover. Understanding the optimal farm configuration to support insectivorous bird and bat populations can assist farmers to make informed decisions regarding in-crop natural pest control and maximise the predation services provided by farm biodiversity.

Wastewater treatment works change the intestinal microbiomes of insectivorous bats.

Mammals, born with a near-sterile intestinal tract, are inoculated with their mothers’ microbiome during birth. Thereafter, extrinsic and intrinsic factors shape their intestinal microbe assemblage. Wastewater treatment works (WWTW), sites synonymous with pollutants and pathogens, receive influent from domestic, agricultural and industrial sources. The high nutrient content of wastewater supports abundant populations of chironomid midges (Diptera), which transfer these toxicants and potential pathogens to their predators, such as the banana bat Neoromicia nana (Vespertilionidae), thereby influencing their intestinal microbial assemblages. We used next generation sequencing and 16S rRNA gene profiling to identify and compare intestinal bacteria of N. nana at two reference sites and two WWTW sites. We describe the shared intestinal microbiome of the insectivorous bat, N. nana, consisting of seven phyla and eleven classes. Further, multivariate analyses revealed that location was the most significant driver (sex, body size and condition were not significant) of intestinal microbiome diversity. Bats at WWTW sites exhibited greater intestinal microbiota diversity than those at reference sites, likely due to wastewater exposure, stress and/or altered diet. Changes in their intestinal microbiota assemblages may allow these bats to cope with concomitant stressors.

Ecological and Conservation Significance of Herpesvirus Infection in Neotropical Bats.

Bats are the second most diverse order of mammals and key species for ecosystem functioning, providing a wide range of ecosystem services, from pest control to seed dispersal. Chiropterans are known for hosting a large diversity of viruses, in some cases with little or no effect to their health. Here, we report on the results of a screening for DNA (Herpesviridae) and RNA viruses (Rhabdovirus and Pneumovirus), finding a high prevalence and wide diversity of both Beta- and Gamma-Herpesvirus in insectivorous and hematophagous bats of the southern cone of South America. Our findings suggest that bats in the southern neotropics harbor a high diversity of herpesviruses and, at least in some cases, the viral community in the bat species is more strongly associated with ecological traits of the hosts, rather than their taxonomy. The presence of a separate clade into the Gammaherpesvirinae subfamily in the common vampire bat suggests the independent circulation of herpesviruses in hematophagous and insectivorous bats and highlights the properness of these viruses to track vampire bats’ population structure for rabies studies. Hence, we suggest that as other pathogens viruses may be used to track the population dynamics of their hosts, including movement and demographics.Supplementary InformationThe online version contains supplementary material available at 10.1007/s10393-021-01530-2.

MRI Image Segmentation Using Bat Optimization Algorithm with Fuzzy C Means (BOA-FCM) Clustering

Functional and anatomical information extraction from Magnetic Resonance Images (MRI) is important in medical image applications. The information extraction is highly influenced by the artifacts in the MRI images. The feature extraction involves the segmentation of MRI images. We present a MRI image segmentation using Bat Optimization Algorithm (BOA) with Fuzzy C Means (FCM) clustering. Echolocation of bats is utilized in Bat Optimization Algorithm. The proposed segmentation technique is evaluated with existing segmentation techniques. Results of experimentation shows that proposed segmentation technique outperforms existing methods and produces 98.5% better results.

Acoustical Investigation of Bats in Selçuklu District of Konya Province

Based on the shape and model of echolocation calls, the acoustic definition of insectivorous bat species has become a successful tool for revealing the use of different habitats, activity and behaviour patterns. Many researchers have used ultrasonic detectors to identify bat species and assess habitat use. This method has become particularly valuable for species that are difficult to capture. In this study, a total of 3167 bat passages were recorded in the Selçuklu district of Konya province, by using an ultrasonic detector. As a result of the survey, 6 species (Myotis myotis / blythii, Barbastella barbastellus, Pipistrellus pipistrellus, Hypsugo savii, Eptesicus serotinus and Miniopterus schreibersii) were analysed. B. barbastellus and E. serotinus were recorded acoustically for the first time in the study area. ANOVA analysis showed that there were no significant differences in the call parameters between the locations where M. myotis / blythii, B. barbastellus, P. pipistrellus and M. schreibersii species were recorded. Discriminant Function Analysis (DFA) was performed to classify 5 species (M. myotis / blythii, B. barbastellus, P. pipistrellus, H. savii and M. schreibersii). As a result of the DFA, the species were classified as 100%.

Development of a species identification system of Japanese bats from echolocation calls using convolutional neural networks

Bats inhabit all continents except Antarctica, and they have enormous potential as bioindicators. Therefore, monitoring bats helps us to understand the surrounding environmental changes. However, bats are nocturnal, which makes it difficult to visually monitor their behavior. This paper proposes a bat species identifier method based on the analysis of ultrasound called echolocation calls, which is a promising method to monitor bats' activity levels effectively. We develop a robust method to identify the bat species with improved accuracy by analyzing their echolocation calls. First, 1400 sound files with four families, 13 genera, and 30 species were recorded in Japan and the Jincheon-gun in South Korea from 1999 to 2019. Bat echolocation calls were detected from the sound files and used to generate 54,525 spectrograms by applying short-time Fourier transform. We developed a deep learning–based bat species identifier using convolutional neural networks with MobileNetV1 used as the model's architecture. Furthermore, we applied nested cross-validation with the Bayesian optimization algorithm to search for the optimal combination of hyperparameters and evaluate the expected performance. We achieved 98.1% accuracy, which outperformed previous studies that treated more than 30 bat species. We visualized important regions of the spectrograms which correspond to prediction using the Guided Grad-CAM. Moreover, we discussed how to treat the noise class and minimize the model training time. Then, we proposed potential solutions to boost the identifier's performance, the generalization of the echolocation call recording protocols, and applicable techniques to improve the identification accuracy. Future perspectives are 1) to change the deep learning algorithm from image classification to object detection and 2) to apply the proposed identifier to unknown bat echolocation calls to evaluate the feasibility of estimating bat fauna and spatial activity distribution.

Olfactory tracking strategies in a neotropical fruit bat.

ABSTRACTMany studies have characterized olfactory-tracking behaviors in animals, and it has been proposed that search strategies may be generalizable across a wide range of species. Olfaction is important for fruit- and nectar-feeding bats, but it is uncertain whether existing olfactory search models can predict the strategies of flying mammals that emit echolocation pulses through their nose. Quantitative assessments of how well echolocating bats track and localize odor sources are lacking, so we developed a behavioral assay to characterize the olfactory detection and tracking behavior of crawling northern yellow-shouldered bats (Sturnira parvidens), a common neotropical frugivore. Trained bats were presented with a choice between control and banana-odor-infused solutions in a series of experiments that confirmed that bats are able to locate a reward based on odor cues alone and examined the effect of odor concentration on olfactory search behaviors. Decision distance (the distance from which bats made their change in direction before directly approaching the target) was distinctly bimodal, with an observed peak that coincided with an inflection point in the odor concentration gradient. We observed two main search patterns that are consistent with both serial sampling and learned route-following strategies. These results support the hypothesis that bats can combine klinotaxis with spatial awareness of experimental conditions to locate odor sources, similar to terrestrial mammals. Contrary to existing models, bats did not display prominent head-scanning behaviors during their final approach, which may be due to constraints of nasal-emitted biosonar for orientation.

Body mass explains digestive traits in small vespertilionid bats.

Bats are unique among mammals in that they have evolved the capacity to fly. This has generated strong selective pressure on the morphology and function of their digestive system. Given that in bats intestinal length and nominal surface-area are proportional to body mass, this trait importantly relates to explaining some of their digestive characteristics. We described the relationship between digestive traits and body mass of four species of bats of the family Vespertilionidae living in a montane ecosystem in central Mexico. We calculated food transit time, apparent dry matter digestibility, and defecation rate in feeding trials under captive conditions. We also: (1) built a model of the relationship between digestive traits and body mass to determine if this association was consistent within the members of the family Vespertilionidae, and (2) mapped these traits along the phylogeny to explore how digestive characteristics may have evolved. In our feeding trials, body mass was positively related to transit time and negatively related to apparent dry matter digestibility. The model predicted accurately the transit time in bats with body mass < 20g. The phylogenetic approach suggested that over the evolutionary history of the family, transit time decreased as digestibility increased. Because of the results obtained here, it is likely that for most bats of the family Vespertilionidae, adaptations in digestive traits to process food have followed evolutionary changes in their body mass. We discuss these findings in a physiological and ecological context.

Rickettsia spp. in bats of Romania: high prevalence of Rickettsia monacensis in two insectivorous bat species

BackgroundSpotted fever group rickettsiae represent one of the most diverse groups of vector-borne bacteria, with several human pathogenic species showing an emerging trend worldwide. Most species are vectored by ticks (Ixodidae), with many zoonotic reservoir species among most terrestrial vertebrate groups. While the reservoir competence of many different vertebrate species is well known (e.g. birds, rodents and dogs), studies on insectivorous bats have been rarely performed despite their high species diversity, ubiquitous urban presence and importance in harboring zoonotic disease agents. Romania has a high diversity and ubiquity of bats. Moreover, seven out of eight SFG rickettsiae species with zoonotic potential were previously reported in Romania. Based on this, the aim of this study was to detect Rickettsia species in tissue samples in bats.MethodsHere we report a large-scale study (322 bats belonging to 20 species) on the presence of Rickettsia spp. in Romanian bat species. Tissue samples from insectivorous bats were tested for the presence of Rickettsia DNA using PCR detection amplifying a 381 bp fragment of the gltA gene. Positive results were sequenced to confirm the results. The obtained results were statistically analyzed by chi-squared independence test.ResultsPositive results were obtained in 14.6% of bat samples. Sequence analysis confirmed the presence of R. monacensis in two bat species (Nyctalus noctula and Pipistrellus pipistrellus) in two locations.ConclusionThis study provides the first evidence of a possible involvement of these bat species in the epidemiology of Rickettsia spp., highlighting the importance of bats in natural cycles of these vector-borne pathogens.Graphical

Postnatal growth and development of Natalus mexicanus (Chiroptera: Natalidae)

Natalus mexicanus is a bat species distributed from northern México to Central America. It inhabits various types of tropical vegetation, roosting mainly in caves with high relative humidity and temperature, and feeding mostly on arachnids. This study investigated postnatal growth and flight development of populations under natural conditions inhabiting “Los Laguitos” cave, Chiapas, southern México. Forty-four females and 50 males were monitored from birth to 55 days of age; at five-day intervals, we measured body mass, forearm length, cartilaginous epiphyseal gap of the fourth metacarpal-phalangeal joint, and development of four characters. We used statistical analyses and growth models to quantify the changes in morphometric parameters. Neonates are altricial; the ears began to unfold since day one, while the eyes opened at day 25. Greyish hair appeared between 25 to 35 days. Forearm length and body mass increased linearly over 35 days, then the growth rate decreased. The cartilaginous epiphyseal gap increased in size until day 25 and then started to close. The logistic equation yielded the best fit for forearm length (K = 0.07) and body mass (K = 0.10). Sustained flight was first achieved at 35 days of age. N. mexicanus neonates are altricial and relatively small compared with other bats. Eye-opening and fur development took place at a slower rate than in most species of insectivorous bats. In the Chiapas population, eye-opening, fur development, and volancy occurred more slowly relative to the population inhabiting Álamos, Sonora. These differences are probably consequences of local variations. The morphometric postnatal growth pattern of N. mexicanus was like that of other insectivorous bats, i. e., linear growth rate before the onset of flight and slowing down thereafter. As in other studies, the logistic model best fitted the growth pattern of body mass and forearm length, but growth coefficients were lower versus other tropical bats. The cartilaginous epiphyseal gap of the fourth digit closes at an intermediate age relative to other insectivorous bats. Sustained flight was attained when the relative body mass and forearm length of individuals approached adult body dimensions, as in other bat species.

Adverse effects of noise pollution on foraging and drinking behaviour of insectivorous desert bats

Human-generated noise can deleteriously affect many animals. Echolocating bats, which crucially depend on sound for their activity, might therefore serve as bioindicators to quantify the ecological effects of sound pollution. While the influence of sound pollution on animal behaviour has been widely studied, the impact of music is almost unknown. We tested whether music, broadcast loudly, affects bats’ foraging and drinking behaviour. The study was done at two waterbodies, where bats drink and forage in the Negev Desert, Israel, during summertime, when water availability is limited: both sites, one isolated natural pond and one artificial waterbody, frequently host recreational parties and concerts. We broadcast music whose frequency range did not overlap with that of bat echolocation calls, and acoustically assessed bat activity before and after the music broadcast. At the remote waterbody, used by bats as a drinking site, the number of bat passes did not vary between treatments. However, after music was broadcast, bats performed significantly more unsuccessful drinking attempts. At the artificial waterbody—a foraging site—activity decreased significantly after music was broadcast. Additionally, music had a cumulative effect on bats, since overall activity significantly decreased over the experimental period. Noise may affect bats by narrowing their attention or distracting them from their primary task. Broadcasting loud music near remote waterbodies is, therefore, significantly hazardous for bats and other wildlife.

First Detection of Bat Astroviruses (BtAstVs) among Bats in Poland: The Genetic BtAstVs Diversity Reveals Multiple Co-Infection of Bats with Different Strains.

Background: Astroviruses (AstVs) are common pathogens of a wide range of animal hosts, including mammals and avians, causing gastrointestinal diseases, mainly gastroenteritis and diarrhea. They prompt a significant health problem in newborns and young children and economic losses in the poultry sector and mink farms. Recent studies revealed a growing number of bat species carrying astroviruses with a noticeable prevalence and diversity. Here, we demonstrate the first detection of bat astroviruses (BtAstVs) circulating in the population of insectivorous bats in the territory of Poland. Results: Genetically diverse BtAstVs (n = 18) were found with a varying degree of bat species specificity in five out of 15 bat species in Poland previously recognized as BtAstV hosts. Astroviral RNA was found in 12 out of 98 (12.2%, 95% CI 7.1–20.2) bat intestines, six bat kidneys (6.1%, 95% CI 2.8–12.7) and two bat livers (2.0%, 95% CI 0.4–7.1). Deep sequencing of the astroviral RNA-dependent RNA polymerase (RdRp) region revealed co-infections in five single bat individuals with highly distinct astrovirus strains. Conclusions: The detection of highly distinct bat astroviruses in Polish bats favors virus recombination and the generation of novel divergent AstVs and creates a potential risk of virus transmission to domestic animals and humans in the country. These findings provide a new insight into molecular epidemiology, prevalence of astroviruses in European bat populations and the risk of interspecies transmission to other animals including humans.

Loss of sweet taste despite the conservation of sweet receptor genes in insectivorous bats

The evolution of taste perception is usually associated with the ecology and dietary changes of organisms. However, the association between feeding ecology and taste receptor evolution is unclear in some lineages of vertebrate animals. One example is the sweet taste receptor gene Tas1r2 Previous analysis of partial sequences has revealed that Tas1r2 has undergone equally strong purifying selection between insectivorous and frugivorous bats. To test whether the sweet taste function is also important in bats with contrasting diets, we examined the complete coding sequences of both sweet taste receptor genes (Tas1r2 and Tas1r3) in 34 representative bat species. Although these two genes are highly conserved between frugivorous and insectivorous bats at the sequence level, our behavioral experiments revealed that an insectivorous bat (Myotis ricketti) showed no preference for natural sugars, whereas the frugivorous species (Rousettus leschenaultii) showed strong preferences for sucrose and fructose. Furthermore, while both sweet taste receptor genes are expressed in the taste tissue of insectivorous and frugivorous bats, our cell-based assays revealed striking functional divergence: the sweet taste receptors of frugivorous bats are able to respond to natural sugars whereas those of insectivorous bats are not, which is consistent with the behavioral preference tests, suggesting that functional evolution of sweet taste receptors is closely related to diet. This comprehensive study suggests that using sequence conservation alone could be misleading in inferring protein and physiological function and highlights the power of combining behavioral experiments, expression analysis, and functional assays in molecular evolutionary studies.

Bats (Chiroptera) of Bidoup Nui Ba National Park, Dalat Plateau, Vietnam

We determined species diversity, seasonal reproduction, and echolocation patterns in the bat community of Bidoup Nui Ba National Park (BNBNP), Lam Dong Province, on the Dalat Plateau of the Central Highlands of Vietnam. We documented 27 species with 211 individuals captured in 26 994 m2 mist-net-hours and 3015 m2 harp-trap-hours of effort. We found five species of pteropodids and 22 species of insectivorous bats in four families, including regional records and species seldom captured in Vietnam. Bat species richness at BNBNP is now known to be 33 species, including six found in a prior study. Based on the inverse Simpson Index of Diversity, evenness of captures was low, reflecting the high abundance of a few species with many species documented by just one or two individuals. Insectivorous bats were pregnant in the late dry season, but not during the wet season when lactation occurred and volant juveniles were captured. Echolocation call characteristics were determined for 19 species of insectivorous bats. Call patterns were consistent with some but not all reports in the literature from elsewhere in southeast Asia. This suggests the existence of cryptic species or geographic and habitat variability in echolocation calls of southeast Asian bats that requires further study.

Occurrence and diversity of Sarcocystidae protozoa in muscle and brain tissues of bats from São Paulo state, Brazil.

Studies on infectious and emerging diseases caused by bats have been increasing worldwide due to their well-recognised status as a reservoir species for various infectious agents as well as their close relationship to humans and animals. This study reports the molecular frequency and diversity of the parasites belonging to the Sarcocystidae family in bats in São Paulo state, Brazil. A total of 2892 tissue samples (brain and pectoral muscle/heart homogenates) from 1921 bats belonging to 36 species were collected, and the Sarcocystidae protozoan 18S ribosomal RNA encoding genes (18S rDNA) were detected by nested PCR and Sanger sequencing. The relative prevalence of Sarcocystidae species was 4.7% (91/1921) among 16 bat species, including insectivorous (n = 65), frugivorous (n = 13) and nectarivorous (n = 11) bats. From 66 sequenced positive samples, 50 were found to be suitable for analysis. Ten samples from insectivorous and nectarivorous bats showed 100% similarity with Neospora caninum (n = 1), Hammondia hammondi (n = 1), Cystoisospora canis (n = 1), Nephroisospora eptesici (n = 1), Sarcocystis (Frenkelia) glareoli (n = 1), and Toxoplasma gondii (n = 5). The 45 non-T. gondii samples revealed 15 different 18S rDNA alleles with identities varying from 96.1 to 100% with several Sarcocystidae species, which might suggest that bats can harbour a large variety of Sarcocystidae organisms. From the five T. gondii-positive tissue samples, three samples from two different bat specimens of the insectivorous Eumops glacinus were characterised using 11 PCR-restriction fragment length polymorphism (RFLP) markers, revealing the non-archetypal ToxoDB genotypes #6 (type BrI), which is one of the most prevalent in different hosts and regions from Brazil, and #69. We recommend the inclusion of T. gondii as a differential diagnosis for rabies and other neurological syndromes in bats.

Mammals of Mt. Pinatubo, Luzon Island, Philippines: Extreme Resilience Following Catastrophic Disturbance

The catastrophic eruption of Mt. Pinatubo in 1991 destroyed the forests that covered the peak and impacted the surrounding habitat over a broad area of central Luzon. Information on the mammal fauna of Mt. Pinatubo prior to the eruption is limited but documents a variety of native mammals. In 2011 and 2012, we surveyed mammals at localities along an elevational gradient on the eastern slope of the mountain where vegetation had been devastated by pyroclastic flows and subsequent lahars, and habitat reflected early stages of plant succession. We documented eight species of bats (five fruit bats and three insectivorous bats), seven species of small nonvolant mammals (two non-native and five native rodents), and two native large mammals. Additional species of bats and non-volant mammals present in the vicinity of Mt. Pinatubo prior to the eruption or recently documented at other localities in the Zambales Mountains may be present in remnant forest habitat elsewhere on Pinatubo. Across five survey localities where habitat was in the early stages of regeneration, native species of small non-volant mammals were more widespread and much more abundant than were non-natives. The most abundant native species, Apomys sacobianus, may be endemic to Mt. Pinatubo. It is an extreme example of a “disturbance specialist” that thrives in a severely disturbed habitat. Results underscore the disturbance tolerance of many native small mammals of Luzon and reveal a resilience that is remarkable for a highly endemic insular fauna. Mt. Pinatubo presents opportunities for further studies on how natural disturbance has shaped the evolution of the Philippine biota and may influence its future conservation.