Northern Bats Research Articles

Large‐scale long‐term passive‐acoustic monitoring reveals spatio‐temporal activity patterns of boreal bats

The distribution ranges and spatio‐temporal patterns in the occurrence and activity of boreal bats are yet largely unknown due to their cryptic lifestyle and lack of suitable and efficient study methods. We approached the issue by establishing a permanent passive‐acoustic sampling setup spanning the area of Finland to gain an understanding on how latitude affects bat species composition and activity patterns in northern Europe. The recorded bat calls were semi‐automatically identified for three target taxa; Myotis spp., Eptesicus nilssonii or Pipistrellus nathusii and the seasonal activity patterns were modeled for each taxa across the seven sampling years (2015–2021). We found an increase in activity since 2015 for E. nilssonii and Myotis spp. For E. nilssonii and Myotis spp. we found significant latitude ‐dependent seasonal activity patterns, where seasonal variation in patterns appeared stronger in the north. Over the years, activity of P. nathusii increased during activity peak in June and late season but decreased in mid season. We found the passive‐acoustic monitoring network to be an effective and cost‐efficient method for gathering bat activity data to analyze spatio‐temporal patterns. Long‐term data on the composition and dynamics of bat communities facilitates better estimates of abundances and population trend directions for conservation purposes and predicting the effects of climate change.

BIOLOGY OF <i>EPTESICUS NILSSONII</i> (VESPERTILIONIDAE, CHIROPTERA) IN THE MIDDLE URALS, SVERDLOVSK REGION

In the Middle Urals, Sverdlovsk Region, detailed information, both previously published and new, is provided on the bat species inhabiting urbanized areas, as well as data on the biology of the species wintering in caves. Stationary studies of the biology of Eptesicus nilssonii Keyserling et Blasius 1839 were carried out during the period of activity outside the caves. Reproductive groups of animals and the autumn rut in summer habitats are described for the first time.

Variability in bat morphology is influenced by temperature and forest cover and their interactions.

Multiple climatic and landscape drivers have been linked to variations in bat body size and wing functional traits. Most previous studies used proxies rather than actual climate and land-use data, and their interactions are rarely explored. We investigate whether higher summer average temperatures are driving decreasing bat body size as predicted by Bergmann's rule or increasing appendage size as per Allen's rule. We also explore whether temperature or resource availability (namely forest cover) is responsible for changes in wing functional traits. Using land-use data from historical maps and national statistics combined with climatic data, we assessed the effect of temperature and resource availability on bat morphology. We used 464 museum specimens of three bat species (Eptesicus nilssonii, Pipistrellus pygmaeus, and Plecotus auritus), spanning 180 years, across a 1200 km latitudinal gradient. We found no evidence of higher summer average temperatures driving decreases in body size in bats. Jaw sizes of P. auritus and P. pygmaeus changed over time but in different directions. The geographical variation of forest cover was also related to differences in wing functional traits in two species. Crucially, there was a significant antagonistic interactive effect of forest and temperature on tip index in P. pygmaeus whereby above 14.5°C the relationship between forest and tip index actually reversed. This could indicate that higher temperatures promote more pointed wings, which may provide energetic benefits. Our results show the importance of including both climatic and land-use variables when assessing trends in bat morphology and exploring interactions. Encouragingly, all three species have shown an ability to adapt their body size and functional traits to different conditions, and it could demonstrate their potential to overcome future negative impacts of climate and land-use change.

The presence of wind turbines repels bats in boreal forests

Impacts of wind power on bats are usually evidenced by the recorded fatalities, while other impacts are not well understood or considered during project planning. However, wind turbines may affect use of the surrounding habitats by bats. Little is known about such impact, especially in the European boreal biogeographical region. We studied the consequences of operating wind turbines on the presence and activity of bats in forests. We simultaneously monitored bat acoustic activity at 84 sampling sites placed at 200 m intervals from 0 to 1.000 m (2 recorders per distance class), over four months and at seven Finnish wind farms located in forested habitats. Our results show higher presence and activity at 600 m and further from turbines for Eptesicus nilssonii, and higher presence at 800 m and further for Myotis spp. We also saw an increase in bat activity during midsummer, which may be due to increased use of forest canopy cover during the short nights at this time. These results indicate a potential loss in habitat quality around wind turbines, e.g., a greater number of open areas in forests unfavourable to certain bat species. This lower activity and presence could also be an indication for active avoidance of the wind turbines from the bats. Furthermore, these results are the first of their kind for Eptesicus nilssonii, and for the European boreal biogeographical region. They show undeniable impacts of wind power on bats in Finland, and enforce the requirement for better consideration of bats during the development of such projects in Finland. Similarly, these results show impacts of operating turbines on habitat use by bats, impacts that now must be considered in Europe. We also call for investigation on the causative mechanisms of the observed effect, to better facilitate mitigation.

Determining the different phases of torpor from skin- or body temperature data in heterotherms

Technological innovations have made heat-sensitive data-loggers smaller, more efficient and less expensive, which has led to a growing body of literature that measures the skin- or body temperatures of small animals in their natural environments. Studies of this type on heterothermic endotherms have prompted much debate regarding how to best define ‘torpor’ expressions from skin- or body temperature data alone. We propose a new quantitative method for defining torpor ‘entries’, ‘arousals’ and ‘stable torpor periods’ whilst comparing the results to ‘torpor bout’ durations identified using only the torpor cut-off method. By decomposing a torpor bout into ‘entries’, ‘stable torpor periods’, and ‘active arousals’, we avoid biases introduced by using strict threshold temperature values for the onset of torpor, thereby allowing better insight into individual use of torpor. We present our method as an easy-to-use function written in R-code, offering an un-biased and consistent methodology to be applied on skin- or body temperature measurements across datasets and research groups. When testing the function on a large dataset of skin temperature data collected on three bat species in Norway (Plecotus auritus: Nind = 39; Eptesicus nilssonii: Nind = 11; Myotis brandtii: Nind = 10), we identified 461 complete torpor bouts across species. More than 40% of the torpor bouts (Nbouts = 192) did not contain stable torpor periods, because the bats aroused before they had reached a stable skin temperature level. Furthermore, only considering ‘torpid’ and ‘euthermic’ temperature values by applying strict cut-off thresholds led to potentially large underestimations of torpor bout durations compared to our quantitative determination of the onset and termination of each torpor bout. We highlight the importance of differentiating between torpor phases, especially for active arousals that can be very energetically expensive and may alter our evaluation of the actual energetic savings gained by an individual employing torpor.

Seasonal Changes in Body Mass and Activity of Digestive Enzymes in Eptesicus nilssonii (Mammalia: Chiroptera: Vespertilionidae) during Hibernation

Seasonal Changes in Body Mass and Activity of Digestive Enzymes in Eptesicus nilssonii (Mammalia: Chiroptera: Vespertilionidae) during Hibernation

Data on the summer bat fauna of Belarus in 2017–2020

This report presents the results of the bat fauna survey carried out in Belarus during the warm seasons between 2017 and 2020. The presented data were collected in 31 localities in all six administrative regions (voblasćs) of Belarus during field studies (mist-netting, searching for roosts and colonies, and acoustic surveys) and in the course of the work of the Minsk bat contact centre. Field data refer to 26 localities; acoustic observations to 14 localities; and netting was carried out in 19 localities (151 ind.). The data on bats collected via the contact centre came from 6 localities (35 ind.). In the course of our survey, we recorded 13 out of the 19 species of the Belarusian bat fauna. They are Barbastella barbastellus, Eptesicus nilssonii, E. serotinus, Myotis dasycneme, M. daubentonii, Nyctalus lasiopterus, N. leisleri, N. noctula, Pipistrellus kuhlii, P. nathusii, P. pygmaeus, Plecotus auritus, and V. murinus. The occurrence of all recorded species was confirmed by direct identification. Data on breeding have been added for all recorded species except for N. lasiopterus and B. barbastellus. Data on breeding have been added for all recorded species, except for N. lasiopterus and B. barbastellus. Maternity colonies were recorded for E. serotinus, M. dasycneme (the second record of a maternity colony of the species for the entire period of research in Belarus) and M. daubentonii. The largest number of individuals recorded by the contact centre represent V. murinus; other species in descending order are E. serotinus, N. noctula, P. auritus, P. nathusii, B. barbastellus, M. daubentonii, P. kuhlii, and E. nilssonii. Among the netted individuals, P. nathusii prevailed; other species in descending order were M. daubentonii, P. pygmaeus, E. nilssonii, P. auritus, N. noctula, E. serotinus, M. dasycneme, N. leisleri, and N. lasiopterus. Three species (V. murinus, B. barbastellus, and P. kuhlii) were presented only among bats reported via the contact centre. During the survey, the species P. pipistrellus, Pl. austriacus, M. brandtii, M. nattereri, M. myotis, and M. mystacinus included in the list of mammal species of Belarus were not recorded. The reasons of the lack of records of these six species are discussed. The collected data contribute to the general knowledge on the distribution, breeding, and status of bat species in Belarus and Eastern Europe.

Prevalence and Genetic Diversity of Bartonella Spp. in Northern Bats (Eptesicus nilssonii) and Their Blood-Sucking Ectoparasites in Hokkaido, Japan.

We investigated the prevalence of Bartonella in 123 northern bats (Eptesicus nilssonii) and their ectoparasites from Hokkaido, Japan. A total of 174 bat fleas (Ischnopsyllus needhami) and two bat bugs (Cimex japonicus) were collected from the bats. Bartonella bacteria were isolated from 32 (26.0%) of 123 bats. Though Bartonella DNA was detected in 79 (45.4%) of the bat fleas, the bacterium was isolated from only one bat flea (0.6%). The gltA sequences of the isolates were categorized into genotypes I, II, and III, which were found in both bats and their fleas. The gltA sequences of genotypes I and II showed 97.6% similarity with Bartonella strains from a Finnish E. nilssonii and a bat flea from a E. serotinus in the Netherlands. The rpoB sequences of the genotypes showed 98.9% similarity with Bartonella strain 44722 from E. serotinus in Republic of Georgia. The gltA and rpoB sequences of genotype III showed 95.9% and 96.7% similarity with Bartonella strains detected in shrews in Kenya and France, respectively. Phylogenetic analysis revealed that Bartonella isolates of genotypes I and II clustered with Bartonella strains from Eptesicus bats in Republic of Georgia and Finland, Myotis bats in Romania and the UK, and a bat flea from an Eptesicus bat in Finland. In contrast, genotype III formed a clade with B. florencae, B. acomydis, and B. birtlesii. These data suggest that northern bats in Japan harbor two Bartonella species and the bat flea serves as a potential vector of Bartonella transmission among the bats.

Население и особенности размещения рукокрылых (Chiroptera, Vespertilionidae) г. Екатеринбурга

Bats have been living next to people for a long time, and they have successfully inhabited cities. Abundant information on the peculiarities of their ecology in urban conditions has been obtained for North America, Australia and Europe. Research of this problem for Russia is not numerous and is of interest. This paper presents information on the population of bats in the large industrial city of Yekaterinburg. The main aim is to study the species diversity and spatial distribution of bats, taking into account three factors that determine the quality of the animal habitat in the city (the presence of areas of woody vegetation and water-bodies as a feeding station; various buildings as suitable shelters). Yekaterinburg is located in Russia, close to the Asian-European border (56°50'N, 60°35'E.). Animals were observed and captured during the warm season using a mobile trap and a MAGENTA ELECTRONICS MK II ultrasonic detector (England). Museum materials (Yekaterinburg, Russia, Ural Federal University named after B.N.Yeltsin, Sverdlovsk Regional Museum, Institute of Plant and Animal Ecology UB RAS - IPAE 983653, IPAE 773780) were examined. The study was conducted according to the guidelines of international and national guidelines, and approved by the Ethics Commitee of IPAE UB RAS (protocol №11 29.04.2022). All captured animals were released into nature. Residents reported information about the distribution of animals (125 detection points of bats) for the period 2001-2020. For analysis, two zones of the built-up area of the city without forest parks were identified: zone I - the center and zone II - the remaining built-up part (See Fig. 1). To analyze spatial distribution, distances from the detection points of animals to the nearest squares, alleys, parks, forest parks, floodplain areas and city water-bodies of various sizes were calculated. In the vicinity of encounters and captures, urban buildings are described as sites of potential refuges (material, number of storeys). In total, more than 110 individuals of 5 species were counted during the surveys (See Table 1). The migratory species Vespertilio murinus, and sedentary species wintering in Ural caves - Eptesicus nils-sonii, Myotis daubentonii, M. dasycneme were found in zones I and II. M. brandtii (reported by V.E. Polyakov) was found in the forest-park zone. V. murinus is predominant, and E. nilssonii is the second largest. Both species were found in the city during the warm season (forming brood colonies) and, possibly, they overwinter in the city. Most of the bats were found near brick and panel 2-16-storey houses (See Fig. 2-a). In zone I, the detection points near older 2-6-storey buildings were significantly more frequent (х2 = 3.7; p < 0.05). In zone II, outside the center, the detection points of bats near 9-16 storey buildings were significantly more frequent = 6.4; p < 0.05). Most detections (81%) of bats in the city as a whole were observed in the immediate vicinity or at a distance of 200-500 m from large parks, boulevards, gardens, etc. (See Fig. 2-b). The frequency of detection of bats at a distance of more than 1 km from large plantations is significantly higher in zone II (7.6%, x2 = 8.9-10.1; p < 0.05). In relation to water-bodies, clear dependence in the location of animals was not found (See Fig. 2-c). Most often, bats use feeding stations near small areas of woody vegetation between residential buildings in yards and at a considerable distance from large water-bodies (72% of cases). At these feeding stations (zone I - center), the abundance of insects is lower than in their natural habitat (See Fig. 3). The spatial distribution of bats is associated with the quality of urban development and the presence of areas of woody vegetation, and does not depend on the presence of large water-bodies. It can be assumed that these distribution patterns of bats are due to the ecology of the background species V. murinus. The species diversity of the city's bats is reduced in comparison to their natural habitat (5 species out of 10 inhabit them). Similar reduction of bat species diversity is noted in other cities of Russia and Ukraine (See Table 2). It can be assumed that the low bat species diversity in Yekaterinburg is an indicator of the poor quality of urban greening.

Первые наблюдения за летучими мышами в девственной пещере (пещера Чекановского, Восточная Сибирь)

The cave was mapped by A. Chekanovsky in 1873, but until 2018 it was not visited by people, as it is located in a sparsely populated and difficult to access area. To date, it has been established that this is a complex karst labyrinth with a length of more than 3 km, located in the mountain taiga about 50 km northwest of Lake Baikal (Olkhonsky district of the Irkutsk region). In 2019-2021 the first data on bats (Chiroptera) were collected in the Chekanovsky Cave. Visual observations were carried out at the entrance and inside the cave, 40 bats were caught with mist nets, subfossil remains of bat skeletons (n=1041) were collected. 7 species of bats were found, including 3 species included in the Red Book of Irkutsk region. The frequency of finds based on the results of identifying subfossil skulls was: Plecotus ognevi (78.9%), Murina hilgendorfi (10.5%), Myotis sibirica (10.5%), Myotis ikonnikovi (5.0%), Myotis frater (1.1%), Eptesicus nilssonii (0.3%), Myotis petax (0.1%). Only the first three species are represented in net catches: P. ognevi (81.6%), M. hilgendorfi (12.1%), M. sibirica (2.1%). The modern habitat of M. ikonnikovi and E. nilssonii in the cave was established from photographs and finds of recently dead animals. A group M. hilgendorfi (n=13) that looked sick were discovered in a cave in August 2021. Single specimens of bats of at least 4 species were found in a state of hibernation when examining the cave in late autumn and winter. Signs of swarming were noted in autumn. The discovery of a large number of skeletal remains of bats and the presence of several species of bats in different seasons of the year indicate that the cave has served as an important refuge for these animals for a long time. The cave has not been completely covered and is promising as an object for further scientific research. The results of the first observations of bats are considered as an argument in favor of a positive decision to give the Chekanovsky Cave area the status of a specially protected natural area of regional significance.

Fauna and flight activity of bats in natural forests in the southern Brdy Mts. and the first information on the occurrence of Hypsugo savii in this area (Chiroptera: Vespertilionidae)

The bat fauna was studied at six localities of protected natural forest fragments in the southern part of the Brdy Mts. (south-western Bohemia), in the years 2019–2020. Netting and acoustic detection on line transects were used in order to document the species composition and flight activity of bats at the localities under study. Altogether, 24 individuals of seven bat species were netted. In total, 643 minutes of the presence of flying bats were registered within 56.5 transect hours. With use of these methods, at least 16 bat species were recorded. Of them, Myotis myotis, M. mystacinus / M. brandtii, M. nattereri, Eptesicus nilssonii, Pipistrellus pipistrellus, Plecotus auritus, and Barbastella barbastellus represent the constant species group with respect to their occurrence at the localities. Pipistrellus pipistrellus was the most frequent species (54%), with the highest relative flight activity at all localities. The highest intensity of flight activity of the bat community was observed in habitats with rocks, boulder accumulation, and open stony debris (14.17 min+/h). The highest bat species diversity was registered in habitats with the prevalence of herb-rich mixed beech forest stands (15 species, diversity index H’=2.02; equitability E=0.75). A series of calls of Hypsugo savii was registered in the Na skalách Nature Reserve on 8 May 2020. It represents the first finding of this species in the region of the Brdy Mts.

The influence of night length: Activity of the northern bat Eptesicus nilssonii under conditions of continuous light in midnight sun compared to a southern population

BackgroundNearly all insectivorous bats (Chiroptera) are strictly nocturnal, flying and feeding only between sunset and sunrise despite lower insect availability than by day, most likely to avoid predation by diurnal birds. This may represent a great challenge to bats living north of the Arctic Circle, which are exposed to bright nights in the period of the midnight sun. The northern bat Eptesicus nilssonii was studied at different latitudes in Norway (69, 66 and 58°N) by three techniques; visual counts of exits from and returns to roosts, infrared detection with a datalogger and an ultrasound data recorder, to reveal how their activity varied across latitude, season, and night, as well as across light levels. How does a nocturnal bat adjust to perpetual light and what light levels are tolerated?ResultsIn the north the bats’ active season lasted 2.5 months, 1.5 months shorter than in the south. The bats only flew in 3-4 weeks of midnight sun, and hardly ever left the roost until the sun went behind a hill in the evening. In addition, the timing of their nightly hunting was highly influenced by the darkness of the sky, and they very rarely flew in light levels above 200 foot-candles (FC). As the night became darker than twilight from early August, the bats restricted their activity to between sunset and sunrise. This was the normal situation in southern Norway, where the bats tracked sunset and sunrise throughout the entire season. Those bats appeared to prefer light levels below 100-50 FC and hence, also did fly in twilight conditions.ConclusionsThe willingness to fly in twilight by the southern population may be a prerequisite to the northern bat’s survival in the land of the midnight sun. These bats must accept short nights in the first part of their summer season and must be willing to fly in light levels 2-4 times higher than in the south. Most likely, this depends on a reduced predation risk and good abundance of insects at night.

Winter activity of boreal bats

Natural hibernation sites used by bats in areas that lack cave features have long remained unresolved. To investigate hibernation site selection and winter activity of boreal bats, we recorded bat calls using passive acoustic monitoring at 16 sites in South-Western Finland. These sites included four rock outcrops with crevices and cave features, three glacial erratics or boulder fields, three ancient shores, three root cellars and three control sites where we did not expect bats to be overwintering. Our results revealed echolocation calls of Eptesicus nilssonii, Plecotus auritus and Myotis sp. We recorded significantly more activity near rock outcrops compared to other habitats, excluding root cellars. We also found that ambient temperature had a positive effect on bat activity and found evidence that P. auritus may be using low barometric pressure as a proxy for suitable foraging conditions during the winter. Our results suggest that rock outcrops may be more important to bats than previously acknowledged, highlighting the need to take these sites in account in planning of conservation measures. Furthermore, our findings underline the suitability of using acoustic monitoring in homing on hibernation sites that are not otherwise accessible.

New records of bat flies (Diptera: Nycteribiidae), with an updated checklist of the nycteribiids of Russia.

We assembled a checklist by documenting and curating previously published data as well as previously unpublished records of bat flies from the Russian Federation. A total of 20 bat fly species are listed, belonging to 4 genera. Basilia mongolensis nudior Hůrka, 1972 and Basilia nattereri (Kolenati, 1857) are recorded from Russia for the first time. The following new host associations are reported: Basilia mongolensis nudior ex Myotis nattereri (Kuhl), Basilia nattereri ex Eptesicus nilssonii (Keyserling Blasius), Basilia rybini Hůrka, 1969 ex Myotis dasycneme (Boie) and Eptesicus nilssonii, and Nycteribia quasiocellata Theodor, 1966 ex Vespertilio murinus Linnaeus. We provide data on nine major Russian regions for which nycteribiid records were previously lacking.

Bats of the Prespa Basin in northern Greece: acoustic survey, new records and relationships to light pollution (Chiroptera)

The bat survey in the Greek part of the Prespa basin in 2018–2020 confirmed, despite the limited methods used, its extraordinary importance for bat diversity. The study documented the presence of 22 bat forms (20 species) by acoustic surveys and a favourable status of some roosts including several nursery colonies. Three of the recorded species are here reported for the first time, Eptesicus nilssonii (the first record for Greece), Nyctalus lasiopterus, and Barbastella barbastellus, however, confirmation by a capture or direct observation of an individual is still needed. The collected data showed that bats do not avoid the urbanized parts of the study area and underlined the importance of old houses, churches, and ruins providing suitable roosting and foraging opportunities. The measurements of light pollution in villages revealed a high amount of light diffusion caused by the used type of shieldless luminaires. Heat maps of light intensity revealed a slightly higher bat activity in almost all villages in 2020, upon the situation in 2018. Bat passes were recorded not only in the peripheries of the highest illumination zones but also inside them, although some of the bat passes may belong to bats flying enough in the dark above the light levels of the installed lamps. The study provides application of mitigation actions for the Municipality of Prespa with the main aim to reduce the current level of the ALAN (Artificial Light At Night).

First detection of bat-borne Issyk-Kul virus in Europe

Bats have been gaining attention as potential reservoir hosts of numerous viruses pathogenic to animals and man. Issyk-Kul virus, a member of the family Nairoviridae, was first isolated in the 1970s from vespertilionid bats in Central Asia. Issyk-Kul virus has been described as human-pathogenic virus, causing febrile outbreaks in humans with headaches, myalgia and nausea. Here we describe the detection of a novel strain of Issyk-Kul virus from Eptesicus nilssonii in Germany. This finding indicates for the first time the prevalence of these zoonotic viruses in Europe.

Bats in the collection of the Zoological museum of Belarusian State University

The results of the examination of bat collection of the Zoological Museum of Belarusian State University, Minsk, one of the largest natural history museums in Belarus are presented. The collection contains 226 specimens, collected in 1924-2006, mainly in Belarus (in all administrative regions). In the collection there are specimens of Vespertilionidae: Barbastella barbastellus, Eptesicus nilssonii, E. serotinus, Myotis daubentoni, Myotis ex gr. “mystacinus-brandtii, Nyctalus lasiopterus, N. leisleri, N. noctula, Pipistrellus kuhlii, P. nathusii, P. pipistrellus s. l., Plecotus auritus, Vespertilio murinus; and as well one species of Pteropodidae: Rousettus aegyptiacus. Voucher data were digitized and systematized. The electronic catalog was compiled and conveyed to the Museum. The scientific and historical value of the collection is shown.

New data on bats species diversity in National Park Narochansky (Belarus). Vestsi Natsyyanal ’nai akademii navuk Belarusi

The results of fauna study of National Park Narochansky (Minsk region) during the field seasons 2019-2020 are presented. We performed bat captures using mist nets and also surveyed settlements with an ultrasonic heterodyne detector. 177 specimens of 9 species were captured, specifically: Eptesicus nilssonii (Keyserling et Blasius, 1839), Myotis brandtii (Eversmann, 1845), M. dasycneme (Boie, 1825), M. daubentonii (Kuhl, 1817), Nyctalus noctula (Schreber, 1774), Plecotus auritus (Linnaeus, 1758), Pipistrellus nathusii (Keyserling et Blasius, 1839), P. pygmaeus (Leach, 1825), Vespertilio murinus (Linnaeus, 1758). 11 settlements of bats were discovered and mapped within the study area. According to the mist net captures, the dominant species is P. nathusii, with subdominant M. daubentoniid; andM. brandtii with P. auritus as the rarest species. Other species had represented ratios of 2.7 to 9.5 % in the nets captures. Species E. nilssonii andM. brandtii are only represented by male specimens. We also report the first registered discovery of Myotis brandtii on the territory of National Park Narochansky, which is also the most northern registration of that species in Belarus. In comparison to the previous studies, we have confirmed the presence of several species with previously questionable local status: P. auritus, M. brandtii, M. daubentonii and V. murinus.

Natural and anthropogenic factors influencing the bat community in commercial tree stands in a temperate lowland forest of natural origin (Białowieża Forest)

In 2011–2017, we examined the ecology of bat assemblages in the commercially used stands of the Białowieża Forest, Poland. The species composition was analyzed, as well as the relationship between bat activity and distance to buildings and to open waters. The relationship between bat activity and stand age, type of stand (coniferous vs. deciduous), and tree canopy closure (open vs. dense) was also examined. Bat activity was recorded using full-spectrum ultrasound detectors, with subsequent analysis using specialized software. Bats were recorded on eight linear transects. The following species of bats were found: western barbastelle (Barbastella barbastellus), serotine (Eptesicus serotinus), northern bat (Eptesicus nilssoni), common noctule (Nyctalus noctula), lesser noctule (Nyctalus leisleri), soprano pipistrelle (Pipistrellus pygmaeus), Nathusius’ pipistrelle (Pipistrellus nathusii), common pipistrelle (Pipistrellus pipistrellus), parti-coloured bat (Vespertilio murinus), and bats from the genus Myotis. Bat activity was affected mainly by the canopy structure along a transect, the number of dead trees, and the age of tree stands. The activity of three from five studied open space aerial foraging bat species (serotine bat, northern bat, and parti-coloured bat) was negatively affected by canopy closure along a transect. Canopy cover was not the most important factor for the other two open space bat species - the common noctule and lesser noctule. Canopy closure was also not a primary factor affecting the edge space foragers like species from this genus Pipistrellus. The activity of Nathusius’ pipistrelle was positively correlated with the number of nearby dead trees, whereas the activity of the common pipistrelle was negatively correlated with the upper quartile of trees age. There was no good single environmental variable for the activity of western barbastelle, bats of the genus Myotis and the soprano pipistrelle. However, we found that the activity of western barbastelle and soprano pipistrelle clearly increased among years. The results suggest that commercial forests with limited economic activity are still a suitable environment for forest bats, including rare and endangered species. They also show that the transformation of stands, resulting in anthropogenic open areas, as well as forest roads, allows synanthropic species to penetrate deep into compact stands. We still do not fully know the impact of such a transformation of the fauna on the forest ecosystem, including the impact on vulnerable bat species closely related to forests.

Экологические и физиолого-биохимические адаптации северного кожанка (Eptesicus nilssoniiL.) как фактор доминирования вида в северных широтах

Экологические и физиолого-биохимические адаптации северного кожанка (Eptesicus nilssoniiL.) как фактор доминирования вида в северных широтах