Identifying key research objectives to make European forests greener for bats

Bats are a biodiverse mammal order providing key ecosystem services such as pest suppression, pollination and seed dispersal. Bats are also very sensitive to human actions, and significant declines in many bat populations have been recorded consequently. Many bat species find crucial roosting and foraging opportunities in European forests. Such forests have historically been exploited by humans and are still influenced by harvesting. One of the consequences of this pressure is the loss of key habitat resources, often making forests inhospitable to bats. Despite the legal protection granted to bats across Europe, the impacts of forestry on bats are still often neglected. Because forest exploitation influences forest structure at several spatial scales, economically viable forestry could become more sustainable and even favour bats. We highlight that a positive future for bat conservation that simultaneously benefits forestry is foreseeable, although more applied research is needed to develop sound management. Key future research topics include the detection of factors influencing the carrying capacity of forests, and determining the impacts of forest management and the economic importance of bats in forests. Predictive tools to inform forest managers are much needed, together with greater synergies between forest managers and bat conservationists

Cross-realm assessment of climate change impacts on species' abundance trends

Climate change, land-use change, pollution and exploitation are among the main drivers of species' population trends; however, their relative importance is much debated. We used a unique collection of over 1,000 local population time series in 22 communities across terrestrial, freshwater and marine realms within central Europe to compare the impacts of long-term temperature change and other environmental drivers from 1980 onwards. To disentangle different drivers, we related species' population trends to species- and driver-specific attributes, such as temperature and habitat preference or pollution tolerance. We found a consistent impact of temperature change on the local abundances of terrestrial species. Populations of warm-dwelling species increased more than those of cold-dwelling species. In contrast, impacts of temperature change on aquatic species' abundances were variable. Effects of temperature preference were more consistent in terrestrial communities than effects of habitat preference, suggesting that the impacts of temperature change have become widespread for recent changes in abundance within many terrestrial communities of central Europe.Additionally, we appreciate the open access marine data provided by the International Council for the Exploration of the Sea. We thank the following scientists for taxonomic or technical advice: C. Brendel, T. Caprano, R. Claus, K. Desender, A. Flakus, P. R. Flakus, S. Fritz, E.-M. Gerstner, J.-P. Maelfait, E.-L. Neuschulz, S. Pauls, C. Printzen, I. Schmitt and H. Turin, and I. Bartomeus for comments on a previous version of the manuscript. R.A. was supported by the EUproject LIMNOTIP funded under the seventh European Commission Framework Programme (FP7) ERA-Net Scheme (Biodiversa, 01LC1207A) and the long-term ecological research program at the Leibniz-Institute of Freshwater Ecology and Inland Fisheries (IGB). R.W.B. was supported by the Scottish Government Rural and Environment Science and Analytical Services Division (RESAS) through Theme 3 of their Strategic Research Programme. S.D. acknowledges support of the German Research Foundation DFG (grant DO 1880/1-1). S.S. acknowledges the support from the FP7 project EU BON (grant no. 308454). S.K., I.Kü. and O.S. acknowledge funding thorough the Helmholtz Association’s Programme Oriented Funding, Topic ‘Land use, biodiversity, and ecosystem services: Sustaining human livelihoods’. O.S. also acknowledges the support from FP7 via the Integrated Project STEP (grant no. 244090). D.E.B. was funded by a Landes–Offensive zur Entwicklung Wissenschaftlich–ökonomischer Exzellenz (LOEWE) excellence initiative of the Hessian Ministry for Science and the Arts and the German Research Foundation (DFG: Grant no. BO 1221/23-1).Peer Reviewe

Distribution of bats in Bavaria - effects of land use and climate

Die Arbeit beschreibt zwei Aspekte der Verbreitung von Fledermäusen (Flm.) in Bayern: (1) Die Landschaft im Umfeld der Wochenstuben von 21 Arten und (2) deren potenzielle Verbreitung. (1) Die Landschaft der Wochenstuben wurde in elf konzentrischen Kreisen zwischen 0,5 und 15 km auf der Basis des Digitalen Landschaftsmodells betrachtet. Sieben Flächentypen beschreiben die Topographie: Ackerland, Grünland, Still-/Fließgewässer, Siedlung/Verkehr, Laub-, Nadel-, Mischwald. Präferenzindizes zeigen an, welche Flächentypen im Vergleich zu Bayern über- oder unterrepräsentiert sind. Landschaftsmerkmale für 14 Arten mit mehr als 10 Kolonien: Barbastella barbastellus: stark ländlich geprägt und siedlungsarm. Eptesicus nilssonii: bis auf Kolonienähe gewässer- und nadelwaldreich. E. serotinus: waldarme Landschaften, aber vorhandener Wald laubholzreich. Grün- und Ackerland stark vertreten. Myotis bechsteinii: laubholzreiche Großlandschaft. M. brandtii: mischwaldreiche Landschaften. M. daubentonii: Wald- und gewässerreiche Wiesenlandschaften. M. emarginatus: nur in Südostoberbayern; Grünland überbetont, Laubwald hervorgehoben. M. myotis: mittlerer Waldanteil, erhöhter Laub- und Mischwaldanteil. M. mystacinus: durchschnittliche bayerische Kulturlandschaft mit leichter Betonung von Grünland. M. nattereri: siedlungsarme Landschaft mit quartiernah höherem Waldanteil und erhöhtem Laub-, Mischwald- und Ackeranteil, insgesamt geringer Grünlandanteil und relative Gewässerarmut. N. leisleri: sowohl quartiernah als auch –fern wald- und laubholzreich. Pipistrellus pipistrellus: leicht grünland- und gewässerbetont, im Wald überwiegt Laubholz. Plecotus auritus: sehr ländliche Gebiete mit geringem Siedlungsanteil. Pl. austriacus: Acker überwiegt gegenüber Wald, Laubwaldanteil sehr hoch, sowohl in Bezug auf Bayern- als auch auf Waldfläche. Für die Arten mit weniger als 10 Kolonien haben die Analysen anekdotischen Charakter: Rhinolophus ferrumequinum und hipposideros, Nyctalus noctula, Pipistrellus nathusii, kuhlii und pygmaeus, Vespertilio murinus. Bei der koloniegrößenbezogenen Auswertung des Mausohrs wurden auch Unterschiede zwischen Nord- und Südbayern deutlich. Das Umfeld nordbayerischer Kolonien ist misch- und laubwaldreich, südbayerischer grünland- und gewässerbetonter. Je kleiner die Siedlung und je größer der Anteil von Laub- und Mischwald an der Kreis- oder Naturraumfläche desto größer ist die Kolonie. Größere Kolonien liegen im (laub)waldreicheren Nordbayern. (2) Die potenzielle Verbreitung wurde mit Hilfe von GARP für ein 2x2 km-Raster modelliert. Umweltvariablen setzten sich aus 51 Klimawerten des Bayerischen Klimaatlasses, der Meereshöhe und den sieben Flächentypen zusammen, Sachdaten bildeten alle Sommer- und Wochenstubenfundorte. Arten wurden nach Ähnlichkeit ihrer Verbreitungen gruppiert: Gruppe 1: Mops-, Brandt-, Nord-, Kleine Bartflm. Das Verbreitungsgebiet umfasst größtenteils die Alpen und den Bayer. Wald, Nordwestbayern ist ausgespart. Gruppe 2: Wasser-, Fransenflm., Braunes Langohr. Arealgrößen sind vergleichbar, dieselben Landstriche ausgeschlossen. Lücken bei Wasserflm. und Braunem Langohr sind waldreiche Gebiete (z. B. Spessart). Nordwestbayern erscheint bei der Fransenflm. geschlossen. Gruppe 3: Rauhautflm., Kleinabendsegler, Abendsegler. Die Verbreitung erstreckt sich über das gesamte Flachland bis 600-700 m. Im Nordwesten ist die Verbreitung geschlossener als im übrigen Bayern. Gruppe 4: Bechsteinflm., Graues Langohr. Areale stimmen vor allem im Süden und im Nordosten überein. Das Bechsteinflm.-gebiet ist im Nordwesten beinahe lückenlos, im Alpenvorland endet es nahe 600 m. Beim Grauen Langohr sind große Waldgebiete und Truppenübungsplätze Lücken. Übrige Arten: Breitflügel-, Wimper-, Weißrand-, Mücken-, Zwerg-, Zweifarbflm., Mausohr, Große und Kleine Hufeisennase. Keine auffälligen Gemeinsamkeiten untereinander, aber teilweise Übereinstimmung mit Gruppen 1-4. Aufgrund kleiner aktueller Vorkommen sehr eingeschränktes potenzielles Verbreitungsgebiet bei Wimperflm. (Alpenvorland), Weißrandflm. (städtische Wärminseln), Großer Hufeisennase (östliche Frankenalb). Die Breitflügelflm. identifiziert sich als Tieflandart, Höhenlagen sind nicht modelliert. Auch das Mausohr wird nicht in höheren Lagen gesehen, das Verbreitungsgebiet wirkt durchbrochen. Die Gebiete von Zwerg- und Mückenflm. sind vor allem entlang von Flussläufen ähnlich. Das Gebiet der Kleinen Hufeisennase erstreckt sich entlang der Täler bis in die Alpen, jedoch ohne Niederungen im Flachland und ohne Ballungsräume. Die Zweifarbflm. tritt in 75 % Bayerns auf, schwerpunktmäßig im Südosten, insgesamt bis 600-800 m. Unter Berücksichtigung der Fundortverteilung in Bayern erscheinen die wenig verbreiteten Arten Große Hufeisennase, Weißrand-, Wimper-, Bechsteinflm., Graues Langohr hoch selektiv im Vergleich zu Mops-, Wasser-, Fransen-, Zwerg-, Zweifarb-, Kleiner Bartflm. und Braunem Langohr mit geringer Selektivität. Die übrigen Arten liegen im Mittelbereich.This study describes two aspects of bat distribution in Bavaria: (1) The landscape and land use in the surroundings of nursery colonies of all 21 reproducing bat species and (2) their potential distribution. (1) I determined the landscape and land use in the near (500 m) and far (15 km) surroundings of the colonies by creating eleven concentrical circles around the roost sites and by overlaying them on the Digital Landscape Model (DLM) of Bavaria using a GIS. Seven types of land use describe the topography: agriculture, pasture/grassland, standing and flowing water bodies, settlement/roads, deciduous, coniferous, and mixed forest. By comparing the average proportion of each type of land use with the respective proportion of all of Bavaria, a preference index helps to identify which elements dominate the landscape. Striking results for 14 species with more than ten colonies: Barbastella barbastellus: rural character, few settlements. Eptesicus nilssonii: settlements, water bodies and coniferous forest, except for the direct vicinity. E. serotinus: poor in forests but rich in deciduous trees; pastures and agricultural land dominate. Myotis bechsteinii: deciduous forests over large areas. M. brandtii: rich in mixed forests. M. daubentonii: forest in general, grassland rich in water bodies. M. emarginatus: pasture and deciduous forest. M. myotis: compared to Bavaria average or low proportion of forest, but a relatively high portion of deciduous and mixed forest within the forested area. M. mystacinus: ordinary Bavarian cultural landscape, grassland slightly prominent. M. nattereri: few settlements, but higher portion of general forest near the roosts as well as deciduous, mixed forest and agricultural land; pasture and water bodies lower than average. N. leisleri: forests with deciduous trees. Pipistrellus pipistrellus: pasture and water bodies, deciduous forests predominate within forests. Plecotus auritus: rural areas characterized by a small portion of settlements. Pl. austriacus: agricultural land predominates over forest, but portion of forest rich in deciduous trees is high compared to Bavaria and Bavarian forest area. For species with less than ten nursery colonies analyses are of anecdotic character: Rhinolophus ferrumequinum and hipposideros, Nyctalus noctula, Pipistrellus nathusii, kuhlii and pygmaeus, Vespertilio murinus. Detailed analyses for Myotis myotis showed that colony size depended on the type of landscape: the smaller the portion of settlements and the bigger the portion of deciduous/mixed forests, the larger the colony. This positive relationship also holds for colony size and the portion of deciduous and mixed forest in a biogeographical province. Bigger colonies are located in deciduous-rich Northern Bavaria. (2) I modelled the potential distribution of all 21 species for a 2 x 2 km-grid using the modelling programme GARP. Climate variables (51) taken from the Bavarian Climate Atlas, elevation, and the seven types of land use served as environmental variables (59 in total), all summer records and all colony sites as bat records. Species were grouped according to the similarity of their potential distributions: Group 1: Barbastelle, Brandt’s Bat, Northern Bat, Whiskered Bat. Distribution includes most parts of the Alps and the Bavarian Forest, but Northwest Bavaria (mainly Lower Franconia) is excluded. Group 2: Daubenton’s Bat, Brown Long-eared Bat, Natterer’s Bat. Distributions of Daubenton’s Bat and Brown Long-eared Bat are similar according to the size and the excluded regions. Contrary to these two species, the distribution of Natterer’s Bat includes almost all of Northwest Bavaria. In the lowlands, all three species occur continuously Group 3: Nathusius’ Bat, Leisler’s Bat, Noctule. Distributions cover lowlands up to about 600-700 m. In the Northwest, the distribution appears to be more uniform compared to the rest of Bavaria. Group 4: Bechstein’s Bat, Grey Long-eared Bat. Distributions are congruent particularly at their Southern borders and in the Northeast and encompass more than half of the province. The distribution of Bechstein’s Bat is continuous in the Northwest, except for the Rhön, but in the foothills of the Alps it ends at around 600 m. Large continuous forests and large military training areas appear as gaps for Pl. austriacus. Other species: Serotine, Greater Mouse-eared Bat, Notch-eared Bat, Kuhl’s Pipistrelle, Soprano Pipistrelle, Common Pipistrelle, Greater Horseshoe Bat, Lesser Horseshoe Bat, Parti-coloured Bat. No conspicuous similarities among these species although there are partial similarities with distributions of the other species. I estimated the selectivity of the species with regard to the environmental variables: Greater Horseshoe Bat, Kuhl’s Bat, Notch-eared Bat, Grey Long-eared Bat seem to be more selective compared to Barbastelle, Daubenton’s Bat, Natterer’s Bat, Common Pipistrelle, Parti-coloured Bat, Whiskered Bat and Brown Long-eared Bat

Plasma proteomic profiles differ between European and North American myotid bats colonized by Pseudogymnoascus destructans

Emerging fungal diseases have become challenges for wildlife health and conservation. North American hibernating bat species are threatened by the psychrophilic fungus Pseudogymnoascus destructans (Pd) causing the disease called white‐nose syndrome (WNS) with unprecedented mortality rates. The fungus is widespread in North America and Europe, however, disease is not manifested in European bats. Differences in epidemiology and pathology indicate an evolution of resistance or tolerance mechanisms towards Pd in European bats. We compared the proteomic profile of blood plasma in healthy and Pd‐colonized European Myotis myotis and North American Myotis lucifugus in order to identify pathophysiological changes associated with Pd colonization, which might also explain the differences in bat survival. Expression analyses of plasma proteins revealed differences in healthy and Pd‐colonized M. lucifugus, but not in M. myotis. We identified differentially expressed proteins for acute phase response, constitutive and adaptive immunity, oxidative stress defence, metabolism and structural proteins of exosomes and desmosomes, suggesting a systemic response against Pd in North American M. lucifugus but not European M. myotis. The differences in plasma proteomic profiles between European and North American bat species colonized by Pd suggest European bats have evolved tolerance mechanisms towards Pd infection

Ignoring seasonal changes in the ecological niche of non-migratory species may lead to biases in potential distribution models: lessons from bats

Phenology is a key feature in the description of species niches to capture seasonality in resource use and climate requirements. Species distribution models (SDMs) are widespread tools to evaluate a species’ potential distribution and identify its large-scale habitat preferences. Despite its chief importance, data phenology is often neglected in SDM development. Non-migratory bats of temperate regions are good model species to test the effect of data seasonality on SDM outputs because of their different roosting preferences between hibernation and reproduction. We hypothesized that (1) the output of SDMs developed for six non-migratory European bat species will differ between hibernation and reproduction; (2) models built from datasets encompassing both ecological stages will perform better than seasonal models. We employed a dataset of 470 independent occurrences of bat hibernacula and 400 independent records of nursery roosts of selected species and for each species we developed separate winter, summer and mixed (i.e. generated from both winter and summer occurrences) models. Seasonal and mixed potential ranges differed from each other and the direction of this difference was species-specific. Mixed models outperformed seasonal models in representing species niches. Our work highlights the importance of considering data seasonality in the development of SDMs for bats as well as many other organisms, including non-migratory species, otherwise the analysis will lead to significant biases whose consequences for conservation planning and landscape management may be detrimental

Cross-realm assessment of climate change impacts on species' abundance trends

Climate change, land-use change, pollution and exploitation are among the main drivers of species’ population trends; however, their relative importance is much debated. We used a unique collection of over 1,000 local population time series in 22 communities across terrestrial, freshwater and marine realms within central Europe to compare the impacts of long-term temperature change and other environmental drivers from 1980 onwards. To disentangle different drivers, we related species’ population trends to species- and driver-specific attributes, such as temperature and habitat preference or pollution tolerance. We found a consistent impact of temperature change on the local abundances of terrestrial species. Populations of warm-dwelling species increased more than those of cold-dwelling species. In contrast, impacts of temperature change on aquatic species’ abundances were variable. Effects of temperature preference were more consistent in terrestrial communities than effects of habitat preference, suggesting that the impacts of temperature change have become widespread for recent changes in abundance within many terrestrial communities of central Europe

Serum biomarkers of polyomavirus infection and risk of lung cancer in never smokers

Background: Lung cancer in never smokers is a significant contributor of cancer mortality worldwide. In this analysis, we explored the role of nine human polyomaviruses, including JC virus (JCV), BK virus (BKV) and Merkel cell virus (MCV), in lung cancer development in never smokers as there are data to support that polyomaviruses are potentially carcinogenic in the human lung. Methods: We used multiplex serology to detect serum antibodies to polyomaviruses in a nested case-control design combining lung cancer cases and controls from four cohort studies - NYU Women's Health Study (NYU-WHS), Janus Serum Bank, Shanghai Women's Health Study and Singapore Chinese Health Study (SCHS). Results: The final analyses included 511 cases and 508 controls. Seroprevalence for each polyomavirus showed significant heterogeneity by study, but overall there were no statistically significant differences between cases and controls. In total, 69.1% of the cases and 68.7% of the controls were seropositive for JCV VP1 antibody. Seropositivity for BKV was higher at 89.0% in cases and 89.8% in controls and lower for MCV at 59.3% in cases and 61.6% in controls. Similar results were obtained after adding an additional retrospective case-control study (Xuanwei study) to the analysis. Conclusions: Our results do not support the hypothesis that seropositivity for polyomaviruses is associated with increased lung cancer risk in never smokers. Future research to evaluate relationship between polyomavirus infection and lung carcinogenesis should focus more on evaluating the presence of virus or viral nucleic acids (DNA or RNA) in lung tumour samples. © 2016 Cancer Research UK. All rights reserved