Pipistrellus Nathusii Research Articles

Migratory movements of bats are shaped by barrier effects, sex-biased timing and the adaptive use of winds

BackgroundMigratory bats perform seasonal movements between their summer and winter areas. When crossing ecological barriers, like the open sea, they are exposed to an increased mortality risk due to energetically demanding long-distance flights and unexpected inclement weather events. How such barriers affect bat migratory movements is still poorly known.MethodsTo study bat migration patterns in response to an ecological barrier, we tagged 44 Nathusius’ pipistrelles Pipistrellus nathusii with radio-transmitters on the East coast of the United Kingdom (UK) in spring 2021 and 2022. Subsequently, we assessed their movements to continental Europe using the MOTUS Wildlife Tracking System. We investigated route selection, timing of migration, overall migration speed and the influence of wind on airspeed, groundspeed and flight altitude during migratory overseas flights.ResultsBarrier effects cause migratory movements along the coast, and crossings over sea are shortened by deviating from the general migration direction. Males depart from the UK later in the season compared to females. The overall migration speed of females was 61 km/day and 88 km/day after their last detection in the UK. Our estimated airspeeds during oversea flights correspond well with airspeeds measured in a wind tunnel. Bats use wind adaptively to reduce airspeed when flying under tailwind and increase airspeed when flying under crosswind conditions. Departures over sea coincidence with tailwinds, enabling bats to more than double their airspeed, reaching ground speeds of up to 16.8 m/s (60.5 km/h). Our analysis suggests that bats select altitudes with favourable wind conditions and that they seek altitudes of several hundred meters, possibly extending up to 2,500 m. Low-altitude migration occurs when wind conditions are less favourable.ConclusionsOur study demonstrates that bat migratory movements are highly influenced by barrier effects, sex-biased timing of migration and the adaptive use of winds. The results of our study contribute to a more comprehensive understanding of the decision-making process and adaptations bats employ during their migration. Elucidating bat migration patterns will enable us to develop effective conservation measures, for example in relation to the development and operation of coastal and offshore wind farms.

Mercury in Fur of Bats in Middle Taiga of the European Part of Russia at Low Anthropogenic Exposure

Mercury is considered to be one of the chemical elements posing the greatest threats to the health of most animals and can be transferred from aquatic ecosystems to terrestrial food webs. Many bat species forage above water, and their food sources include aquatic and amphibious organisms. Bats are very sensitive to the slightest changes in the environment. The objective was to determine the accumulation of mercury in the fur of insectivorous bats in summer habitats in an area with limited anthropogenic activity in the conditions of the middle taiga in the northwest European part of the Russian Federation. In the studied species, the average values of the metal’s content (μg/g) increased in the following order: Myotis daubentonii (3.294 ± 0.934), Myotis dasycneme (3.909 ± 0.543), Vespertilio murinus (8.011 ± 1.136), Pipistrellus nathusii (8.366 ± 0.546), and Nyctalus noctula (8.408 ± 1.386). The key factor regarding the mercury accumulation in each bat species is the foraging strategy. The mercury content in the fur of adult bats was higher than in subadults.

Challenges in the Vespertilionidae phylogeny: resolving Pipistrellus nathusii placement and affirming generic status for Asian pipistrelles

Abstract Vespertilionidae is a species-rich family of bats that experienced rapid diversification events and contains many morphologically conserved taxa, resulting in challenges to taxonomic and phylogenetic resolution for members of this family. One example of a challenging group is the pipistrelles, which several studies have recovered as paraphyletic. Pipistrellus nathusii is noteworthy for being recovered either as sister to other European Pipistrellus species, more closely related to Nyctalus, or sister to the clade comprising Nyctalus and European Pipistrellus species. Using a core data set of 6 nuclear introns, and an extended data set of 10 nuclear introns, we employ multiple independent phylogenetic methods that are robust in the presence of incomplete lineage sorting or hybridization to resolve the placement of P. nathusii. In addition, our data confirm the distinction of the Asian Pipistrelle taxa which form a distinct genus sister to the clade comprising Vansonia, Pipistrellus, and Nyctalus.

Summer chiropteran community in the Sergievka Park with the unique dominance of Pipistrellus nathusii on the northern periphery of its distribution range

The study of species on the periphery of their ranges is especially relevant for long-term research in protected areas. The aim of this study is to test the hypothesis that Pipistrellus nathusii on the northern periphery of its range has a clumped distribution with long-term viable breeding centres. The species composition and relative abundance of bats in the park were determined through capturing them with mist nets during the 1997–1998 and 2020–2022 survey periods. Within the 2nd survey period the use of an ultrasonic detector was additionally involved. Stability of the bat species composition in the protected area and a significant difference in the relative abundance between the surveys were revealed (χ2 = 47.31, p < 0.05). During both periods, the bat community in the park exhibited a pronounced dominance of P. nathusii and stable values of its relative abundance (40.7 and 44.2%, respectively). Perennial nursery colonies of Myotis daubentonii, Nyctalus noctula, and P. nathusii have been discovered in the park, which are arguably among the northernmost findings (59.89° N, 29.88° E) in European Russia. The catch rate (6.3 bats per net-night) and acoustic activity of the Chiroptera (16.6 active minutes per detector-hour) on the pond was significantly higher than on the alley and glade. This pattern is typical for all frequently recorded bat species – P. nathusii, N. noctula and Eptesicus nilssonii. According to the results of multiple analysis of variance, the effect of species on acoustic activity was the greatest (η = 24.59%, F = 15.52, p < 0.001). The impact of the habitat and the time since sunset, as well as the pairwise combined impact of these three factors, was also significant and reliable. The sizes of the nursery colonies were determined, which in P. nathusii were record high for the northern periphery of the breeding range, 212 individuals. Evening departures of P. nathusii from the nursery colony on the alley were characterized by their beginning before sunset, and from the nursery colony in the glade after sunset. The intensity of P. nathusii departure from the colony in the forest part of the park is significantly higher (5.3 bats/ min) than in the glade (1.4 bats/min). The fact that large nursery colonies of P. nathusii have existed for decades locally at 60° N latitude suggests the species may have a wider distribution in Eastern Fennoscandia in transformed areas containing old trees. Keywords: bats; South-Eastern Fennoscandia; relative abundance; nursery colonies; acoustic activity; circadian rhythms

A Novel Mastadenovirus from Nyctalus noctula Which Represents a Distinct Evolutionary Branch of Viruses from Bats in Europe.

Bats are natural hosts of a wide variety of viruses, including adenoviruses. European bats are known to carry mastadenoviruses categorized as species B (widespread in European Vespertilionidae bats) and whose taxonomy has not been clarified. We examined fecal samples from Vespertilionidae bats (five species) captured in central Russia and found that 2/12 (16%) were positive for mastadenoviruses. The partial genome of the mastadenovirus was assembled from Pipistrellus nathusii, representing the bat adenovirus species B. The complete genome (37,915 nt) of a novel mastadenovirus was assembled from Nyctalus noctula and named BatAdV/MOW15-Nn19/Quixote. Comparative studies showed significant divergence of the Quixote genome sequence from European bat mastadenoviruses, while the only known virus showing low similarity was the isolate WA3301 from an Australian bat, and together they formed a subclade that separated from other BatAdVs. Phylogenetic and comparative analysis of the protein-coding genes provided evidence that Quixote is related to a novel species within the genus Mastadenovirus, provisionally named "K" (as the next available letter for the species). Phylogenetic analyses revealed that some earlier viruses from Western European bats, for which only partial DNA polymerase genes are known, are most likely members of the tentatively named species "K". Thus, at least two species of mastadenovirus are circulating in bats throughout Europe, from western to eastern areas.

Bat thermoregulation in the heat: seasonal variation in evaporative cooling capacities in four species of European bats

Phenotypic flexibility is an important source of physiological variation in endotherms and plays an integral role in species’ response to rapid environmental changes. Studies of phenotypic flexibility have focused on winter acclimatization and cold endurance, and there are fewer data on summer acclimatization and adjustments in heat dissipation capacity, especially in Temperate-Zone species. We used indirect calorimetry and thermometry to test if thermoregulation at high air temperatures (Ta) varies between spring and summer in four species of European vespertilionid bats: Nyctalus noctula, Pipistrellus nathusii, P. pygmaeus, and P. pipistrellus. We measured subcutaneous body temperature (Tsub), evaporative water loss, and resting metabolic rate while exposing bats to a stepped profile of increasing Ta, from 28 °C–48 °C. We predicted that during summer, bats increase heat tolerance and evaporative cooling capacity, to better tolerate hotter Tas. In contrast, we found lower maximum ratios of evaporative heat loss (EHL) to metabolic heat production (MHP) during summer, but no seasonal differences in maximum Ta tolerated or Tsub. The main cause of this seasonal difference in maximum EHL/MHP seems to be from bats increasing EWL more gradually with increasing Ta in summer than spring, particularly in the smaller Pipistrellus species. Therefore, this seasonal variation in heat-dissipation strategies may reflect enhanced water conservation during summer to avoid dehydration, as bats are confined to roosts for longer and hotter days compared to spring.

A haplotype-resolved reference genome of a long-distance migratory bat, Pipistrellus nathusii (Keyserling & Blasius, 1839).

We present a complete, chromosome-scale reference genome for the long-distance migratory bat Pipistrellus nathusii. The genome encompasses both haplotypic sets of autosomes and the separation of both sex chromosomes by utilizing highly accurate long-reads and preserving long-range phasing information through the use of three-dimensional chromatin conformation capture sequencing (Hi-C). This genome, accompanied by a comprehensive protein-coding sequence annotation, provides a valuable genomic resource for future investigations into the genomic bases of long-distance migratory flight in bats as well as uncovering the genetic architecture, population structure and evolutionary history of Pipistrellus nathusii. The reference-quality genome presented here gives a fundamental resource to further our understanding of bat genetics and evolution, adding to the growing number of high-quality genetic resources in this field. Here, we demonstrate its use in the phylogenetic reconstruction of the order Chiroptera, and in particular, we present the resources to allow detailed investigations into the genetic drivers and adaptations related to long-distance migration.

Blood Serum Amino Acid Pool of European Migratory Chiroptera Vespertilio murinus Linnaeus, 1758 and Pipistrellus nathusii Keyserling et Blasius, 1839 of the Ural Fauna.

The pool of free amino acids (AAs) in the blood serum was studied in two European migratory bat species, Vespertilio murinus and Pipistrellus nathusii, of the Urals. Bats from this year's bloods were examined, and significant differences were observed in main metabolic groups of free AAs, including glycogenic (GGAAs), nonessential (NEAAs), essential (EAAs), and sulfur-containing (SCAAs) AAs (p < 0.05). Based on the percent content of the metabolic groups in the total AA pool, GGAAs (79.7%) and EAAs (49.4%) were found to predominate in P. nathusii, and GGAAs (74.9%) and NEAAs (58.4%), in V. murinus. No difference in AAA and BCAA contents was observed between V. murinus and P. nathusii (p > 0.05). The migratory species were shown to significantly differ in the metabolic groups of serum AAs from the resident species Myotis dasycneme (p < 0.05).

Functional activity of the blood system of two migratory species of the Ural

The presented data on the study of the functional activity of the blood system of migratory species of the fauna of the Urals: Vespertilio murinus [Linnaeus, 1758], and Pipistrellus nathusii Keyserling et [Blasius, 1839]. Multivariate nonparametric analysis of variance of red blood parameters (p 0.05) of migrating bats and the sedentary pond bat showed significant species differences. In bats, a certain genetically determined multidirectionality in the mobilization of emergency regulation mechanisms of the lymphoid blood system of sedentary and migratory species has been noted.

Unusual finding of chewing louse Quadraceps cf. junceus (Scopoli, 1763) (Phthiraptera: Ischnocera) on Nathusius pipistrelle Pipistrellus nathusii (Keyserling &amp;amp; Blasius, 1839) (Mammalia: Chiroptera) with review of findings of lice reported from bats

Bats (Chiroptera) do not possess any specific louse species however, rare accidental registrations of this ectoparasites on chiropterans occur. Herein we report for the first time, identification of the lice Quadraceps cf. junceus (Ischnocera: Philopteridae) from vesper bat Pipistrellus nathusii (Keyserling &amp; Blasius, 1839) (Chiroptera: Vespertilionidae) in Belarus. In addition, we provide and discuss previous findings about lice collected from bats.

Bats (Chiroptera, Vespertilionidae) of the Bashkiria National Park

In 2018, 2019, 2021 and 2022 in the national park “Bashkiria” located in the southeastern part of the Republic of Bashkortostan, studies of the local fauna of bats (Mammalia: Chiroptera) were carried out. The uniqueness of the specially protected natural area lies in the presence of linden-maple-oak forests located on the eastern border of their range and a wide variety of surface and deep relief forms associated with the development of karst rocks. As a result, data on the habitation of 12 species of bats, which belong to six genera of the Vespertilionidae family, were obtained. Of these, eight species are included in the regional Red Book. The species Nyctalus lasiopterus, listed in the Red Book of the Russian Federation, was found in the Republic of Bashkortostan for the fi rst time. A cadastre is presented with a description of the places of work, geographical coordinates and results of catches, information on wintering places, the nature of stay in the region, reproduction, age and sex composition of populations, indicators of relative abundance. According to traps, the most numerous in the national park are: Pipistrellus nathusii, Vespertilio murinus, Myotis brandtii, Nyctalus noctula, M. daubentonii and Plecotus auritus. Few species are: Eptesicus nilssonii, M. mystacinus, N. leisleri and M. dasycneme, while M. nattereri and N. lasiopterus are rare. In addition to the identifi ed species, Pipistrellus pygmaeus, discovered by us 30 km south of the borders of the national park, can live on the territory. Recommendations on the protection of bats and the introduction of N. lasiopterus into the Red Book of the Republic of Bashkortostan are presented.

Bats (Chiroptera) of the Ujście Warty National Park and the surrounding area

Bat research was carried out in 2012-2013 in the Ujście Warty National Park and in adjacent areas. Bats were caught in chiropterological nets, searched for in winter and summer roosts. Detector listening was carried out and the owls' diet was analyzed for the presence of bats among their prey. In the national park area, 11 species of bats were detected, and together with the Natura 2000 area "Ujście Warty" and the neighbouring areas, a total of 15 species were detected: the Daubenton's bat Myotis daubentonii, Natterer's bat Myotis nattereri, Brandt's bat Myotis brandtii, noctule bat Nyctalus noctula, serotine bat Eptesicus serotinus, common pipistrelle bat Pipistrellus pipistrellus, soprano pipistrelle bat Pipistrellus pygmaeus, Nathusius' pipistrelle bat Pipistrellus nathusii, brown long-eared bat Plecotus auritus, gray long-eared bat Plecotus austriacus, western barbastelle bat Barbastella barbastellus, greater mouse-eared bat Myotis myotis, Bechstein's bat Myotis bechsteinii, pond bat Myotis dasycneme and the parti-coloured bat Vespertilio murinus. The bat fauna of this area is relatively rich compared to other protected areas and presented results constitute an important supplement to the knowledge about the vertebrate fauna of the national park and its vicinity.

Сучасна теріофауна лівобережжя Каньйонового Придністер’я

The article analyses the current state of the mammal fauna of part of Podolian Transnistria, which lies between the rivers Zbruch and Zolota Lypa (southern Ternopil Oblast, Ukraine). To designate the region, the publication uses a term from old Polish sources—Canyon Transnistria—which reflects the prevailing landform. The area of research in old faunal summaries is mentioned only as part of wider regions, such as Galicia, western Ukraine, or Ternopil Oblast. Over the past decades, the number of publications on the mammal fauna of this particular region has increased substantially, which makes it possible to make a summary overview. The modern mammal fauna of the region comprises 60 species belonging to 7 orders, 20 families, and 41 genera. Over the past 70 years, the mammal fauna of the studied region has undergone significant changes. Its dynamic component is almost 27%. It includes species of recent immigrants (Blyth’s pipistrelle Pipistrellus lepidus, mound-building mouse Mus spicilegus, muskrat Ondatra zibethicus), as well as two species that recovered their range (Eurasian beaver Castor fiber, wildcat Felis silvestris); the dynamic component also includes three extinct or probably extinct species—Geoffroy’s bat (Myotis emarginatus), Podolian ground squirrel (Spermophilus odessanus), and European rabbit (Oryctolagus cuniculus). A group of phantom species has been singled out, which are known only from single old finds, and modern studies of these species are far from sufficient to understand their status. It includes the lesser mouse-eared bat (Myotis oxygnathus), Nathusius’s pipistrelle (Pipistrellus nathusii), southern birch mouse (Sicista loriger), and Podolian mole rat (Spalax zemni). Such species as the long-eared bat (Plecotus austriacus) and the pygmy field mouse (Sylvaemus uralensis) appeared in the lists of the mammal fauna of the region due to changes in taxonomy. The rare component of the mammal fauna comprises 18 species (30%). The article provides a brief description of the current state of mammal populations in the region. Conservation recommendations are given for rare species.

Bats of the Ostrava city and their synantropization

Abstract Based on the published findings (Koštejnová 2013, Slezáková 2014, Gajdošík 2020), unpublished data from museum specimens (2005 – 2013), and data from field surveys (2005 – 2023), a total of 13 bat species were recorded in the urban area of Ostrava in North Moravia. Common species in the area included Pipistrellus pipistrellus, Nyctalus noctula, Eptesicus serotinus, Myotis daubentonii, and Vespertilio murinus. P. pipistrellus was eudominant species (D = 74.41), followed by N. noctula (D = 11.41). E. serotinus was a subdominant species (D = 4.59), followed by M. daubentonii (D = 3.77) and V. murinus (D = 2.45). The occurrence of M. mystacinus/brandtii was recendent (D = 1.33), and the occurrence of M. nattereri (D = 0.51), E. nilssonii (D = 0.51), P. pygmaeus (D = 0.31), Plecotus auritus/austriacus (D = 0.31), Pipistrellus nathusii (D = 0.20), N. leisleri (D = 0.10), M. myotis (D = 0.10) and M. brandtii (D = 0.10) were subrecendent. In the summer season, eudominant species were P. pipistrellus (D = 76.84), followed by the N. noctula (D = 10.63), subdominant E. serotinus (D = 4.74), and M. daubentonii (D = 3.89), with M. mystacinus/brandtii being recendent (D = 1.37). In the winter season, eudominant species were V. murinus (D = 62.50), followed by the N. noctula (D = 34.38) and subdominant P. nathusii (D = 3.13). However, the species composition inside and outside buildings differed significantly. In the summer season, eudominant species inside buildings was P. pipistrellus (D = 99.57), followed by the subrecendent species V. murinus (D = 0.29) and M. daubentonii (D = 0.14). Outside buildings, N. noctula (D = 40.16) were eudominant, followed by E. serotinus (D = 17.72), P. pipistrellus (D = 14.17), and M. daubentonii (D = 14.17), with M. mystacinus/brandtii (D = 5.12) was dominant, and M. nattereri (D = 1.97), E. nilssonii (D = 1.97), P. pygmaeus (D = 1.18), and P. auritus/austriacus (D = 1.18) were recendent species. In the winter season, eudominant species inside buildings were V. murinus (D = 68.75), followed by N. noctula (D = 25.00), and the situation was very similar outside the buildings during this period, with eudominant V. murinus (D = 56.25) and N. noctula (D = 43.75). Two roosts of the maternity colonies P. pipistrellus were recorded in city buildings: in Výškovice, Lumírova 10, in a expansion joint near the balcony on the top floor of a panel residential building; and in Zábřeh, Plzeňská 2617/4 and Plzeňská 2617/6, in expansion joints on the top floors of an old panel building used as a hostel and apartment building.

Functional Activity of the Blood System in Two Migratory Bat Species of the Urals.

Functional activity of the blood system was studied in two migratory Ural species, Vespertilio murinus Linnaeus, 1758 and Pipistrellus nathusii Keyserling et Blasius, 1839. A multivariate nonparametric ANOVA of red blood parameters showed significant interspecific differences (p < 0.05) between the migrating bats and the resident species pond bat. A certain genetically determined multidirectionality in the mobilization of emergency regulation mechanisms of the lymphoid blood system was observed in bats.

Presence of coronaviruses in the common pipistrelle (P. pipistrellus) and Nathusius´ pipistrelle (P. nathusii) in relation to landscape composition.

Changes in land use can modify habitat and roosting behaviour of bats, and therefore the transmission dynamics of viruses. Within bat roosts the density and contact rate among individuals increase and may facilitate the transmission of bat coronaviruses (CoVs). Landscape components supporting larger bat populations may thus lead to higher CoVs prevalence, as the number of roosts and/or roost size are likely to be higher. Hence, relationships between landscape composition and the presence of CoVs are expected to exist. To increase our understanding of the spread and shedding of coronaviruses in bat populations we studied the relationships between landscape composition and CoVs prevalence in the species Pipistrellus pipistrellus and Pipistrellus nathusii. Faecal samples were collected across The Netherlands, and were screened to detect the presence of CoV RNA. Coordinates were recorded for all faecal samples, so that landscape attributes could be quantified. Using a backward selection procedure on the basis of AIC, the landscape variables that best explained the presence of CoVs were selected in the final model. Results suggested that relationships between landscape composition and CoVs were likely associated with optimal foraging opportunities in both species, e.g. nearby water in P. nathusii or in areas with more grassland situated far away from forests for P. pipistrellus. Surprisingly, we found no positive association between built-up cover (where roosts are frequently found) and the presence of bat-CoVs for both species. We also show that samples collected from large bat roosts, such as maternity colonies, substantially increased the probability of finding CoVs in P. pipistrellus. Interestingly, while maternity colonies of P. nathusii are rarely present in The Netherlands, CoVs prevalence was similar in both species, suggesting that other mechanisms besides roost size, participate in the transmission of bat-CoVs. We encourage further studies to quantify bat roosts and colony networks over the different landscape compositions to better understand the ecological mechanisms involved in the transmission of bat-CoVs.

Molecular detection of Babesia vesperuginis in bats from Lithuania

Babesia vesperuginis is an intraerythrocytic protozoan parasite that circulates among bats and ticks in many countries worldwide. However, the distribution of B. vesperuginis in the Baltic region has not been studied. A total of 86 dead bats from eight different species were collected and screened for Babesia spp. using real-time PCR. Overall, 52.3% (45/86) of the bats were found positive for Babesia spp. The prevalence of Babesia spp. in different organs varied, with the highest prevalence observed in heart tissues (37.0%) and the lowest in liver tissues (22.2%). However, the observed differences in prevalence among organs were not statistically significant. Blood samples from 125 bats of nine different species were also analyzed for Babesia spp. prevalence using real-time PCR and nested PCR. The results showed a prevalence of 35.2% and 22.4%, respectively. Moreover, 28.3% (17/60) of the examined blood samples were confirmed positive for Babesia spp. through blood smear analysis. The total of 32 partial sequences of the 18S rRNA gene derived in this study were 100% identical to B. vesperuginis sequences from GenBank. In eight species of bats, Pipistrellus nathusii, Pipistrellus pipistrellus, Pipistrellus pygmaeus, Vespertilio murinus, Eptesicus nilssonii, Eptesicus serotinus, Myotis daubentonii and Nyctalus noctula, Babesia parasites were identified. In E. nilssonii, Babesia spp. was identified for the first time.

Bats (Chiroptera) of spruce forests in the Ukrainian Carpathians

Bat communities in monoculture spruce plantations (Skolivski Beskydy NNP, Gorgany (NNP Syniohora) and Chornohora areas) and spruce forests of the upper mountain forest belt (Verkhovynskyi NNP, Karpatskyi NNP) were studied by recording echolocation calls to assess the importance of such ecosystems for this group of animals. 11 species were recorded at the sample plots: Northern bat Eptesicus nilssonii, Serotine bat Eptesicus serotinus, Brand’s bat/Whiskered bat Myotis brandtii/mystacinus, Daubenton’s bat Myotis daubentonii, Greater mouse-eared bat Myotis myotis, Common noctule Nyctalus noctula, Brown long-eared bat Plecotus auritus, Nathusius’s bat Pipistrellus nathusii, Common pipistrelle Pipistrellus pipistrellus, Soprano pipistrelle Pipistrellus pygmaeus, Parti-coloured bat Vespertilio murinus. According to the degree of dominance (total number of registered calls), E. nilssonii was the most numerous (32.7%). M. mystacinus/brandtii (25.6%) and P. nathusii (18.9%) were somewhat less numerous. According to the spatial distribution (presence in the sample plots), only the pair M. mystacinus/brandtii was detected in all the studied plots. Of the other species, E. nilssonii (58.8%) and P. nathusii (41.2%) were most frequently represented. For the sibling species M. mystacinus/M. brandtii no special habitat requirements were found, but the high frequency of their observations in all ranges of forest biotopes shows them as typical "forest". The dominance of E. nilssonii in spruce forests confirms that this species mainly uses semi-boreal coniferous forests in the Central Europe. The highest value of Shannon's biodiversity index was found in spruce forests of lower altitudes, Skolivski Beskydy NNP (H' = 1.616) and Syniohora NNP (H' = 1.627). Probably, coniferous forests at lower altitudes can be more favourable foraging biotopes for representatives of populations that are not topically associated with such forests: P. pygmaeus, P. pipistrellus, V. murinus, N. noctula. The observed level of nocturnal activity and species diversity of bats in spruce forests suggests that they may be important to their local populations. Coniferous monocultures can play an important role for local bat populations by acting as migratory corridors and foraging sites.

Bidirectional movements of Nathusius’ pipistrelle bats (Pipistrellus nathusii) during autumn at a major migration corridor

Migration is well documented for many species throughout the animal kingdom. Although migration is also a common behaviour in bats, it is rarely studied due to the cryptic nature of the phenomenon. Recoveries of banded individuals have shown that Nathusius' pipistrelles (Pipistrellus nathusii) can fly more than 2000 km between their summer and winter ranges in Europe, but further details of how and where they move between the endpoints of their seasonal journeys remain elusive. Here, we used three-dimensional acoustic tracking at a coastal migration corridor to elucidate the flight behaviour of Nathusius' pipistrelles during late summer. Analyzing 432 recorded flight trajectories, we show that the majority of bats followed the expected southerly direction, parallel to the coastline, on all nights, and flying at the optimal speed for long-distance travel with minimal energy expenditure. However, on one day with stronger winds, about 20 % of the bats flew in the opposite, i.e. northerly, direction. The observation of a proportion of individuals flying antiparallel to the mass of migrating conspecifics within the same movement corridor highlights that individuals may follow contrasting movement strategies at the same time and place, presumably depending on environmental conditions. We argue that it is possible for Nathusius’ pipistrelles to fly back and forth (south and north) during autumn migration, spending more time on this migration corridor than required for a straight one-way flight. This highlights the urgent need to protect migration corridors along coastlines, particularly as wind energy development continues.

Acoustic monitoring reveals spatiotemporal occurrence of Nathusius’ pipistrelle at the southern North Sea during autumn migration

Seasonal movements between the summer and winter areas are a widespread phenomenon in bats So far, most information on the migration ecology of bats has been obtained by studies in terrestrial habitats, whereas scientific knowledge on migration over sea is scarce. We performed continuous ultrasonic acoustic monitoring at 13 locations in the southern North Sea during four consecutive years (2017–2020) and analysed the spatiotemporal occurrence of Nathusius’ pipistrelle Pipistrellus nathusii during autumn migration in relation to weather parameters and lunar phase. Our analysis showed that the main autumn migration of Nathusius’ pipistrelle at the southern North Sea occurs from mid-August until late October and most bats within the study area occur off the Noord Holland coast. North Sea crossings frequently last longer than one night; the day is spent roosting at an offshore structure. The strongest migration occurs during nights with tailwinds from the east-northeast, but bats are also recorded offshore with low to moderate headwinds or crosswinds. Bat presence decreased between the full moon and the last quarter and increased just before the new moon. Finally, our observations show that the occurrence of bats at sea was reduced in 2020 in comparison to the previous years. The results of this study show clear spatiotemporal patterns of migratory bat occurrence at the southern North Sea. The spatial distribution can be used in spatial planning of future offshore wind farms, whereas the temporal occurrence and environmental factors that shape offshore migration can be used to develop mitigation measures to reduce the number of bat fatalities.