Bat Nyctalus Research Articles

Trophic ecology and predation of the greater Noctule bat (Nyctalus lasiopterus) in Russia

The trophic ecology of Nyctalus lasiopterus in the Samara Bend during 2008-2010 has been studied. It has been revealed that the main feeding stations for this species are old ecotonal black poplar stands and willow groves. N. lasiopterus keeps to opportunistic foraging by using easily accessible and properly sized food objects. Having analyzed 129 fecal samples, we singled out 10 categories of food objects belonging to six orders of insects. The representatives of Lepidoptera constitute the major part of the ration. Their abundance rates undergo asynchronous changes relative to each other. Homoptera and Neuroptera are found more rarely in the feces. Orthoptera and Diptera are extremely rare. Besides insects, bird feathers were found in 14 faecal samples of N. lasiopterus. They made up from 60 to 90% of the total fecal mass.

Long distance migration of female Leisler’s bat (Nyctalus leisleri) from Italy to Poland

The routes followed by migratory bat populations occurring in Italy are practically unknown. We herewith report on the capture of a female Leiskler’s bat Nyctalus leisleri occurred in Poland, Wielkopolska province (Greater Poland), district Ostrzeszow, in a forest near the village of Jesiona. The specimen, caught on 5 August 2012, had been previously (23 September 2010) banded in Italy in the Nature State Reserve of Pian degli Ontani (Cutigliano, Pistoia Province, Italy, 44° 06’ 27 N, 10° 41’ 33 E; ring code WWF-ITALY C0524). The minimum straight distance between the two sites is ca. 960 km. This record is the first that proves the existence of migration in Italian populations of N. leisleri and shows that a long NE-SW migration route – one of the longest recorded in Europe by N. leisleri – is followed. The observation remarks once again the importance of a large-scale, trans-national planning of bat conservation.

Selection of roosting habitats by Nyctalus noctula and Nyctalus leisleri in Białowieża Forest—Adaptive response to forest management?

Tree dwelling bats select cavities in large, old, dying or dead trees. This inevitably brings them into direct conflict with the interests of forest managers, who are trained to fell such trees. Therefore the identification of forest stands providing optimal roosting opportunities for bats is crucial, in order to provide appropriate guidelines for forest management. It is also important to identify the extent to which the roosting ecology of bats changes in response to habitat modification. Białowieża Forest (BF) offers a unique opportunity, in the temperate zone, to observe differences between areas with no direct human intervention and managed areas and in particular to reveal the effect of forest management on the roosting ecology of forest dwelling bat species. We used GIS techniques to evaluate bats’ spatial response to changes in forest structure and to test the hypotheses that the forest dwelling bats Nyctalus noctula and Nyctalus leisleri prefer roost sites within old deciduous or wet woodlands over young and coniferous ones and that roost site preferences reflect the extent to which dead and dying trees are removed. There was a significant difference in the selection of roosting habitat between the managed and pristine areas of the forest. Within the pristine forest, both species displayed a strong preference for roost trees located within old deciduous stands (>100 years), whereas in the managed part of the forest old wet woodland was preferred while all medium and young forest stands were avoided. Our data reveal a high degree of lability in the selection of roosting habitat by bats. It appears that bats are able to respond to changes in their environment by changing their roost site preferences and could therefore occupy habitat previously considered less suitable.

Echolocation Calls of Bats from Madeira Island: Acoustic Characterization and Implications for Surveys

Acoustic surveys represent a powerful tool to assess bat distribution and habitat preferences and are widely applicable to monitoring and conservation schemes. However, their correct application requires the development of robust and reliable identification procedures. Little information is available on the bats of Madeira Island (Portugal), particularly their ecological requirements, distribution and population trends, and proper guidelines for their monitoring and conservation have yet to be defined. In this study, we present the first analysis of echolocation calls from species occurring on the island to provide a tool for bat identification during acoustic surveys. Seven hundred and ninety one time-expanded recordings of search phase echolocation calls in cluttered and uncluttered habitats of the Macaronesia endemic pipistrelle Pipistrellus maderensis, Madeira Leisler's bat Nyctalus leisleri verrucosus and grey long-eared bat Plecotus austriacus were analysed and an acoustic repertoire with their temp...

The sensory basis of roost finding in a forest bat,Nyctalus noctula

Tree cavities are a critical resource for most forest-dwelling bats. Yet, it is not known how bats search for new sites and, in particular, find entrances to cavities. Here, we evaluated the importance of different sensory channels for the detection of tree roosts by the noctule bat Nyctalus noctula. Specifically, we tested the role of three non-social cues (echo information, visual information and temperature-related cues) and two social sensory cues (conspecific echolocation calls and the presence of bat olfactory cues). We set up an experiment in a flight room that mimicked natural conditions. In the flight room, we trained wild-caught bats kept in captivity for a short while to find the entrance to an artificial tree cavity. We measured the bats' hole-finding performance based on echolocation cues alone and then presented the bat with one of four additional sensory cues. Our data show that conspecific echolocation calls clearly improved the bats' performance in finding tree holes, both from flying (long-range detection) and when they were crawling on the trunk (short range detection). The other cues we presented had no, or only weak, effects on performance, implying that detection of new cavities from a distance is difficult for noctules if no additional social cues, in particular calls from conspecifics, are present. We conclude that sensory constraints strongly limit the effectiveness of finding new cavities and may in turn promote sociality and acoustic information transfer among bats. As acoustic cues clearly increased the bats' detection performance, we suggest that eavesdropping is an important mechanism for reducing the costs of finding suitable roosts.

The recovery of Nyctalus lasiopterus (SCHREBER, 1780) (Chiroptera: Vespertilionidae) in Turkey

The vespertilionid bat Nyctalus lasiopterus (SCHREBER, 1780) was recovered in the Eastern Karadeniz. This is second record from Turkey, an unusual roosting site for the species formed by an oil drilling platform at sea, is discussed together with other biologi- cal aspects.

Bats' Conquest of a Formidable Foraging Niche: The Myriads of Nocturnally Migrating Songbirds

Along food chains, i.e., at different trophic levels, the most abundant taxa often represent exceptional food reservoirs, and are hence the main target of consumers and predators. The capacity of an individual consumer to opportunistically switch towards an abundant food source, for instance, a prey that suddenly becomes available in its environment, may offer such strong selective advantages that ecological innovations may appear and spread rapidly. New predator-prey relationships are likely to evolve even faster when a diet switch involves the exploitation of an unsaturated resource for which few or no other species compete. Using stable isotopes of carbon and nitrogen as dietary tracers, we provide here strong support to the controversial hypothesis that the giant noctule bat Nyctalus lasiopterus feeds on the wing upon the multitude of flying passerines during their nocturnal migratory journeys, a resource which, while showing a predictable distribution in space and time, is only seasonally available. So far, no predator had been reported to exploit this extraordinarily diverse and abundant food reservoir represented by nocturnally migrating passerines.

Mitochondrial DNA variation and population structure of the island endemic Azorean bat (Nyctalus azoreum).

The Azorean bat Nyctalus azoreum is the only endemic mammal native to the remote archipelago of the Azores. It evolved from a continental ancestor related to the Leisler's bat Nyctalus leisleri and is considered threatened because of its restricted and highly fragmented distribution. We studied the genetic variability in 159 individuals from 14 colonies sampled throughout the archipelago. Sequences of the D-loop region revealed moderate but highly structured genetic variability. Half of the 15 distinct haplotypes were restricted to a single island, but the most common was found throughout the archipelago, suggesting a single colonization event followed by limited interisland female gene flow. All N. azoreum haplotypes were closely related and formed a star-like structure typical of expanded populations. The inferred age of demographic expansions was consistent with the arrival of founder animals during the Holocene, well before the first humans inhabited the Azores. Comparisons with a population of N. leisleri from continental Portugal confirmed not only that all N. azoreum lineages were unique to the archipelago, but also that the current levels of genetic diversity were surprisingly high for an insular species. Our data imply that the Azorean bat has a high conservation value. We argue that geographical patterns of genetic structuring indicate the existence of two management units.

Azorean Bats Nyctalus azoreum, Cluster as they Emerge from Roosts, Despite the Lack of Avian Predators

We tested the hypothesis that clustering in the behaviour of emerging bats is a response to the risk of avian predation. We hypothesised that if avian predation was the cause of clustering, bats in the prolonged absence of avian predators, would not cluster or would cluster less during their emergences. We studied the Azorean bat (Nyctalus azoreum) in the Azores Archipelago. The Azores have a depauperate fauna with no raptorial birds likely to predate bats. The Azorean bat is an endemic mammal to the archipelago, which has an unusually extensive degree of diurnal activity that has been hypothesised to reflect release from the risk of diurnal predation by raptors. Contrary to our prediction Azorean bats clustered during emergence to the same extent as bat species which occur where there are raptors. Two interpretations of these data are possible. First, the hypothesis that the behaviour is anti-predatory may be incorrect. Most of the variation in clustering was explained by variation in ambient temperature...

Seasonal patterns in activity and habitat use by bats (Pipistrellus spp. and Nyctalus leisleri) in Northern Ireland, determined using a driven transect

AbstractThe seasonal activity of Leisler's bat Nyctalus leisleri and pipistrelle bats Pipistrellus spp. with respect to minimum bat numbers and habitat use were investigated in County Down, Northern Ireland using a driven transect from April 1998 to October 1998. Data were collected in lowland farmland near Belfast, Northern Ireland using two BatBox III bat detectors tuned to detect both species and species groups simultaneously. The number of bats/km increased during April, May and June, peaking in July and tailed off after this period. The main peak in July is assumed to reflect the occurrence of newly volant young. An increase in the number of pipistrelle social calls during August and September probably represented mating activity. Bat activity correlated with temperature in both N. leisleri and Pipistrellus spp., although bat numbers were independent of temperature after the middle of June. There was significant variation in habitat use by pipistrelle bats along roads over the study period. Pipistrelle bats were observed in greater numbers in areas of tree‐line, cut hedge (≤1 m high) and deciduous woodland, and increased further when these habitats bordered both sides of the road. Nyctalus leisleri was found in similar numbers in all habitat types and there was no seasonal variation in habitat use. The validity of this method for revealing seasonal variation in bat numbers and habitat use is discussed. Ambient climatic conditions may affect the number of bats recorded, while some species with long‐range echolocation calls, such as N. leisleri, may defy analysis of habitat associations.

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Polymorphic microsatellite loci in vespertilionid bats isolated from the noctule bat Nyctalus noctula.

Polymorphic microsatellite loci in vespertilionid bats isolated from the noctule bat Nyctalus noctula.

Polymorphic microsatellite loci in vespertilionid bats isolated from the noctule bat Nyctalus noctula

Polymorphic microsatellite loci in vespertilionid bats isolated from the noctule bat Nyctalus noctula

Foraging ecology of Leisler's bat (Nyctalus leisleri) at two sites in southern Britain

Foraging ecology of Leisler's bat (Nyctalus leisleri) at two sites in southern Britain

Foraging ecology of Leisler's bat (Nyctalus leisleri) at two sites in southern Britain

AbstractLeisler's bat Nyctalus leisleri was studied at sites around Bristol and Kent in southern Britain. Its diet was studied by faecal analysis, and habitat use was monitored by radio‐telemetry and time‐expanding bat‐detectors. The diet, which varied between the two sites and also with the season, consisted primarily of small Nematoceran Diptera plus smaller numbers of Coleoptera and Lepidoptera. Foraging ranges were relatively large – bats flew a mean maximum distance of 4.2 km from the roost. Minimum area convex polygons enclosed an average of 7.4 km2, but were up to 18.4 km2. Bats significantly preferred foraging in areas of woodland and along scrub‐lined roads in Kent, but over pasture around Bristol. Urban and arable areas were avoided at both sites. Bat‐detector transects showed a significant preference for bats to forage along woodland margins.

Evening emergence of two nursery colonies of Leisler's bat (Nyctalus leisleri) in Ireland

Evening emergence of two nursery colonies of Leisler's bat (Nyctalus leisleri) in Ireland

Evening emergence of two nursery colonies of Leisler's bat (Nyctalus leisleri) in Ireland

AbstractAt one nursery roost of Leisler's bat Nyctalus leisleri, the first bat often, and over half of the colony exceptionally, left before sunset. Departure was earlier during the period of lactation, when energy demands were highest. Consequently emergence data had to be standardized to allow for this before investigating possible associations with light intensity and meteorological factors. The importance of such standardization in general is emphasized. Emergence was earlier on overcast nights and was delayed with increased light intensity. The bats in a neighbouring roost, from which fewer data were obtained, also left earlier on overcast evenings, but departure was generally later than in the first roost, and there was no evidence of its being earlier during lactation. These differences between the roosts may be at least partially explained by the difference in size of the exit holes. At both roosts departure was mainly as a series of outbursts, and this was more marked during the first half of emergence. Rate of emergence increased with colony size. It was unusual for the first bat to leave more than 30 min, or for any bat to leave over 60 min, after sunset. Heavy rain inhibited or disrupted emergence.

New ecological data on the noctule bat (Nyctalus noctula Schreber, 1774) (Chiroptera, Vespertilionidae) in two towns of Spain

La Peninsule iberique represente la limite meridionale de repartition de la noctule commune en Europe. Nous presentons des nouvelles donnees ecologiques du comportement de cette espece dans des parcs de deux villes de Navarre (Nord de l'Espagne) qui prouvent sa presence continue toute l'annee. Entre 1995 et 1998, 148 individus ont ete bagues et 56 refuges ont ete localises. Les groupements observes sont composes de mâles sedentaires; d'avril a aout, on a trouve peu de femelles; en revanche, pendant l'accouplement (septembre a novembre) elles sont assez communes et se reunissent en harems. On montre aussi la rarete des femelles par rapport aux mâles en automne 1997.

Analysis of the diet of Leisler's bat (Nyctalus leisleri) in Ireland with some comparative analyses from England and Germany

The diet of Leisler's bat Nyctalus leisleri was investigated by analysis of droppings collected from six mainly pastoral sites in Ireland, two sites in England (one mainly pastoral, one arable predominating) and three in Germany (in forest), and comprised mainly medium-sized and small insects caught in flight, many of which were probably from swarms. There was a major pastoral prey component, indicated mainly by Scathophaga stercoraria, Scarabaeoidea and associated Acari, at the Irish sites (estimated as 29–55%) and the English pastoral site (22%), but this was less significant elsewhere (1–12%). Insects with aquatic larvae (Ephemeroptera, Trichoptera, Chironomidae/Ceratopogonidae, Culicidae) often made up an important part of the diet (4–39%). Another distinct component, the Lepidoptera, Hemerobiidae, Chrysopidae and Ichneumonidae, which were all intercorrelated in the results, possibly indicates feeding near trees. This component was most important at the German (36–63%) and English arable (30%) locations, but of less significance at the English pastoral (11%) and Irish (2–19%, mean 6%) ones. The diets in Germany were otherwise diverse.

Analysis of the diet of Leisler's bat (Nyctalus leisleri) in Ireland with some comparative analyses from England and Germany

AbstractThe diet of Leisler's bat Nyctalus leisleri was investigated by analysis of droppings collected from six mainly pastoral sites in Ireland, two sites in England (one mainly pastoral, one arable predominating) and three in Germany (in forest), and comprised mainly medium‐sized and small insects caught in flight, many of which were probably from swarms. There was a major pastoral prey component, indicated mainly by Scathophaga stercoraria, Scarabaeoidea and associated Acari, at the Irish sites (estimated as 29–55%) and the English pastoral site (22%), but this was less significant elsewhere (1–12%). Insects with aquatic larvae (Ephemeroptera, Trichoptera, Chironomidae/Ceratopogonidae, Culicidae) often made up an important part of the diet (4–39%). Another distinct component, the Lepidoptera, Hemerobiidae, Chrysopidae and Ichneumonidae, which were all intercorrelated in the results, possibly indicates feeding near trees. This component was most important at the German (36–63%) and English arable (30%) locations, but of less significance at the English pastoral (11%) and Irish (2–19%, mean 6%) ones. The diets in Germany were otherwise diverse.