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The article discusses a study on the foraging behavior, diet and habitat use of Geoffroy's bat, Myotis emarginatus, found in the Mediterranean. The study intends to assist in the assessment of the extent to which habitat use corresponds to differences in habitat availability in various landscapes or if it is a reflection of the lack of selectivity for habitat types, with foraging habitats resulting from dietary preferences. The M. emarginatus foraged mainly in scrubland and pine plantations, occurring near water bodies regardless of main habitat type. The bulk of its diet was constituted by spiders, suited for the hawking foraging style of the M. emarginatus, with an increase in substrates where spiders can build webs in higher vertical vegetation structuring.

We studied the effect of habitat type and prey availability on the foraging decisions of the Mediterranean horseshoe bat (Rhinolophus euryale), a species specialized for cluttered environments. We modeled seasonal habitat selection using radiotelemetry in relation to prey availability in a heterogeneous landscape, determined seasonal diet and prey selection, and used geographic information system data to characterize the landscape surrounding 10 breeding colonies in order to assess the radiotracking results at the population level. Although R. euryale typically has been associated with woodland, our results suggest that the existence of edge habitat, created by semicluttered structures such as hedgerows and woodland edges, was a significant factor in the choice of foraging areas by these bats. Edge habitat was associated with meadows and pastures, creating a landscape highly suited to moths, the preferred prey of R. euryale. In the study area, however, moths were evenly distributed among habitat types; therefore, distribution of moths cannot explain the preference of these bats for semicluttered habitats. The results of our study are consistent with the presumed origin of R. euryale in an edgerich ecosystem (i.e., the savannahs of northern Africa) and establish a new paradigm for how this species uses habitat. This new paradigm, which might also apply to other members of the genus in Europe, should prompt reconsideration of the presumed habitat requirements for this species, and should be incorporated into the conservation policies for the Mediterranean horseshoe bat. [ABSTRACT FROM AUTHOR]

Myotis emarginatus seems fond of spiders and flies, a unique feeding style among European bats. The importance of each prey type varies among studies, so this paper aims to expand on the knowledge to unveil the trophic niche of M. emarginatus by studying its diet changes throughout the maternity season. We sampled five maternity colonies in the Basque Country every 2 weeks for the whole duration of the maternity season and studied their diet using DNA metabarcoding methods. We observed significant changes in diet diversity and composition. At the beginning of the season, M. emarginatus consumed a variety of prey orders, Diptera being the most abundant; but as the season progressed, the relative consumption of Araneae increased. By August, 80% of the weighted percentage of occurrences (wPOO) corresponded to the orb-web-building spider Araneus diadematus. Orb-web-building spiders need habitats of high vertical complexity to grow in abundance. Therefore, conserving them is essential to preserve attractive hunting grounds for colonies of M. emarginatus. Besides, diurnal flies, mainly Stomoxys calcitrans, were also considerably consumed in the colonies studied, which can become detrimental to the well-being of cattle, and can act as a vector of many diseases. [ABSTRACT FROM AUTHOR]

The article presents a study which compared the habitat selection patterns of the Bechstein's bat or Myotis bechsteinii in the Extremadura, southwestern Spain. It discusses the method used in capturing and monitoring the bats, and in categorizing land-use and forest types found in the area. The study shows the variables used in assessing the habitat, the resources available for both foraging and roosting opportunities and the density of the bat population in the area.

Targeted molecular methods such as conventional PCR (cPCR) and quantitative PCR (qPCR), combined with species-specific primers and probes, are widely applied for pest species detection. Besides, the potential of qPCR to quantify DNA in samples makes it an invaluable molecular tool to infer the predation levels on specific prey by analysing predators' stools. Nevertheless, studies on the diet of bats failed to find any empirical relationship, and it remains to be evaluated. Thus, we developed and evaluated two species-specific PCR assays to detect and quantify DNA of a major forest pest, the pine processionary, Thaumetopoea pityocampa, in bats' faeces. Further, we empirically compared a range of different known DNA concentrations (input) of the target species mixed with mocks and bat faecal samples against DNA abundances yielded by qPCR (output) for a quantitative assessment. Overall, cPCR showed a lower detection rate than qPCR, but augmenting the replicate effort from one to three replicates led to a greater increase in the detection rate of the cPCR (from 57 to 80%) than the qPCR (from 90 to 99%). The quantitative experiment results showed a highly significant correlation between the input and output DNA concentrations (t = 10.84, p < 0.001) with a mean slope value of 1.05, indicating the accuracy of our qPCR assay to estimate DNA abundance of T. pityocampa in bat faeces. The framework of this study can be taken as a model to design similar assays applicable to other species of interest, such as agricultural pests or insects of public health concern. [ABSTRACT FROM AUTHOR]

The degree of trophic specialization determines the ability of predators to cope with changing foraging conditions, but in predators that prey on hundreds of species it is challenging to assess, especially when prey identity varies among predator individuals and across space and time.Here, we test the hypothesis that a bat species foraging on flying insects like moths will show ample flexibility in trophic niche, and this irrespective of phylogenetic relationships among moths, so as to cope with a high diversity of prey types that vary across seasons. We predict that individual bats will show functional dietary differences consistent with energetic requirements and hunting skills.We used DNA metabarcoding to determine the diet of 126 Mediterranean horseshoe bats (Rhinolophus euryale) from two different sites during three seasons. Simultaneously, we measured moth availability and characterized the traits of 290 moth taxa. Next, we explored the relationship between phylogeny and traits of all consumed and available moth taxa. Finally, we assessed the relationship between individual traits of bats and traits related to prey profitability, for which we used the RLQ and fourth‐corner statistical techniques.Seasonality was the main factor explaining the functional dietary variation in adult bats, with moths consumed irrespective of their phylogenetic relationships. While adults consumed moths with a broad range in wing loading, body mass and echolocation detection ability, juveniles consumed slower, smaller and lighter moths, which suggests that young individuals may undergo some fitness gain and/or psychomotor learning process during which they would acquire more effective foraging skills.Our approach revealed a degree of functional flexibility in the trophic niche previously unknown for an insectivorous bat. Rhinolophus euryale consumed a wide variety of moth taxa differing in profitability throughout seasons and between ontogenetic stages. We showed the validity of trait‐based approaches to gain new insights in the trophic specialization of predators consuming hundreds of species of prey. [ABSTRACT FROM AUTHOR]

Knowledge on the trophic interactions among predators and their prey is important in order to understand ecology and behaviour of animals. Traditionally studies on the diet composition of insectivorous bats have been based on the morphological identification of prey remains, but the accuracy of the results has been hampered due to methodological limitations. Lately, the DNA metabarcoding and High Throughput Sequencing (HTS) techniques have changed the scene since they allows prey identification to the species level, ultimately giving more precision to the results. Nevertheless, the use of one single primer set to amplify faecal DNA produces biases in the assessed dietary composition. Three horseshoe bats overlap extensively in their distribution range in Europe: Rhinolophus euryale, R. hipposideros and R. ferrumequinum. In order to achieve the deepest insight on their prey list we combined two different primers. Results showed that the used primers were complementary at the order and species levels, only 22 out of 135 prey species being amplified by both. The most frequent prey of R. hipposideros belonged to Diptera and Lepidoptera, to Lepidoptera in R. euryale, and Lepidoptera, Diptera and Coleoptera in R. ferrumequinum. The three bats show significant resource partitioning, since their trophic niche overlap is not higher than 34%. Our results confirm the importance of combining complementary primers to describe the diet of generalist insectivorous bats with amplicon metabarcoding techniques. Overall, each primer set showed a subset of the prey composition, with a small portion of the total prey being identified by both of them. Therefore, each primer presented a different picture of the niche overlap among the three horseshoe bats due to their taxonomic affinity. [ABSTRACT FROM AUTHOR]

Herbivorous arthropods cause immense damage in crop production annually. Consumption of these pests by insectivorous animals is of significant importance to counteract their adverse effects. Insectivorous bats are considered amongst the most voracious predators of arthropods, some of which are known crop pests. In vineyard-dominated Mediterranean agroecosystems, several crops are damaged by the attack of insect pests. In this study we aimed 1) to explore the diet and pest consumption of the lesser horseshoe bat Rhinolophus hipposideros and 2) analyse whether the composition of pest species in its diet changes throughout the season. We employed a dual-primer DNA metabarcoding analysis of DNA extracted from faeces collected in three bat colonies of a wine region in Southwestern Europe during the whole active period of most pest species. Overall, 395 arthropod prey species belonging to 11 orders were detected; lepidopterans and dipterans were the most diverse orders in terms of species. Altogether, 55 pest species were identified, 25 of which are known to cause significant agricultural damage and 8 are regarded as pests affecting grapevines. The composition of pest species in faeces changed significantly with the season, thus suggesting several periods should be sampled to assess the pest consumption by bats. As a whole, the results imply that R. hipposideros acts as a suppressor of a wide array of agricultural pests in Mediterranean agroecosystems. Therefore, management measures favouring the growth of R. hipposideros populations should be considered. [ABSTRACT FROM AUTHOR]

Abstract: Niche partitioning through foraging is a mechanism likely involved in facilitating the coexistence of ecologically similar and co‐occurring animal species by separating their use of resources. Yet, this mechanism is not well understood in flying insectivorous animals. This is particularly true of bats, where many ecologically similar or cryptic species coexist. The detailed analysis of the foraging niche in sympatric, cryptic sibling species provides an excellent framework to disentangle the role of specific niche factors likely involved in facilitating coexistence. We used DNA metabarcoding to determine the prey species consumed by a population of sympatric sibling Rhinolophus euryale and Rhinolophus mehelyi whose use of habitat in both sympatric and allopatric ranges has been well established through radio tracking. Although some subtle dietary differences exist in prey species composition, the diet of both bats greatly overlapped (Ojk = 0.83) due to the consumption of the same common and widespread moths. Those dietary differences we did detect might be related to divergences in prey availabilities among foraging habitats, which prior radio tracking on the same population showed are differentially used and selected when both species co‐occur. This minor dietary segregation in sympatry may be the result of foraging on the same prey‐types and could contribute to reduce potential competitive interactions (e.g., for prey, acoustic space). Our results highlight the need to evaluate the spatial niche dimension in mediating the co‐occurrence of similar insectivorous bat species, a niche factor likely involved in processes of bat species coexistence. [ABSTRACT FROM AUTHOR]

Conservation efforts for endangered animals commonly focus on the protection of foraging habitats, aiming to ensure sufficient food availability. However, the diet of many species is based on animals that undergo habitat shifts across ontogenetic life stages, yielding considerable differences between the lifelong habitat requirements of both predator and prey. Consequently, prey availability may not only depend on the suitability of the foraging grounds where predator and prey coincide, but also on habitats where the ecological requirements of the non-prey stages are fulfilled. In this study we test to what extent prey of the insectivorous bat Rhinolophus euryale (Blasius 1853) originate either from the grounds where they are consumed, or in areas/habitats outside the bat's foraging sites. We analyzed the diet of R. euryale , by identifying its prey to the species level using DNA metabarcoding, and by searching for its prey's larval feeding requirements in the literature. We found that the larvae of the moth prey grow both inside and outside the grounds where they are hunted by the bats once the moths reach their adult stage. The importance of prey that originated from outside the bat's foraging grounds varied considerably across seasons. As a result, R. euryale does not only rely on the landscape elements where it hunts, but also on other source areas/habitats that supply it with food. This study shows that conservation measures that aim to address the foraging requirements of predatory species should not be limited to merely protecting their foraging grounds, but should also take into account the ecological requirements of their prey throughout their life stages. [ABSTRACT FROM AUTHOR]

Introduction: Our purpose was to assess how pairs of sibling horseshoe bats coexists when their morphology and echolocation are almost identical. We collected data on echolocation, wing morphology, diet, and habitat use of sympatric Rhinolophus mehelyi and R. euryale. We compared our results with literature data collected in allopatry with similar protocols and at the same time of the year (breeding season). Results: Echolocation frequencies recorded in sympatry for R. mehelyi (mean = 106.8 kHz) and R. euryale (105.1 kHz) were similar to those reported in allopatry (R. mehelyi 105-111 kHz; R. euryale 101-09 kHz). Wing parameters were larger in R. mehelyi than R. euryale for both sympatric and allopatric conditions. Moths constitute the bulk of the diet of both species in sympatry and allopatry, with minor variation in the amounts of other prey. There were no inter-specific differences in the use of foraging habitats in allopatry in terms of structural complexity, however we found inter-specific differences between sympatric populations: R. mehelyi foraged in less complex habitats. The subtle inter-specific differences in echolocation frequency seems to be unlikely to facilitate dietary niche partitioning; overall divergences observed in diet may be explained as a consequence of differential prey availability among foraging habitats. Inter-specific differences in the use of foraging habitats in sympatry seems to be the main dimension for niche partitioning between R. mehelyi and R. euryale, probably due to letter differences in wing morphology. Conclusions: Coexistence between sympatric sibling horseshoe bats is likely allowed by a displacement in spatial niche dimension, presumably due to the wing morphology of each species, and shifts the niche domains that minimise competition. Effective measures for conservation of sibling/similar horseshoe bats should guarantee structural diversity of foraging habitats. [ABSTRACT FROM AUTHOR]

• Bats showed positive aggregational and functional responses to grape pest abundances. • Not all bat species contribute equally to pest suppression. • Rhinolophus hipposideros is the primary predator of grapevine moths in the study. • The synergistic action of bats from distinct foraging guilds plays a suppressing role. There is growing evidence about the role of insectivorous bats against agricultural pests in various crops. Nevertheless, little research addressed the aggregational and functional responses of bat assemblages to changes in pest availability across a spatio-temporal scale. Therefore, we examined the activity and diet habits of different bat species using DNA metabarcoding by simultaneously monitoring the relative abundance of two major pests (the European grapevine moth, Lobesia botrana , and the leaf rolling tortrix, Sparganothis pilleriana) through the grape growing season, in a vineyard region of the Iberian Peninsula. During pest major irruptions, we found the highest bat activity levels and frequencies of grape pests in the diet of bats, although not all bat species contributed equally to pest suppression. Bats of different foraging guilds positively responded to pest abundances, indicating distinct bat species may synergistically play a role at suppressing agricultural pests at broad scales of the aerospace. For instance, narrow space foragers exploiting major irruptions in grape interior, edge space foragers hampering pest dispersion at local scale, and open space foragers preventing infestations of new grapevine patches at broader scales. Yet, our study exposed the current methodological constraints regarding pest dispersion dynamics, acoustic monitoring of bats' foraging activity or the unfeasibility of metabarcoding to reliably quantify prey abundance in bats diet, and thus further improvement in these issues is required in order to gain insight on the agroecological interactions between bats and pests. [ABSTRACT FROM AUTHOR]