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

White-Nose Syndrome Fungus (Geomyces destructans) in Bats, Europe

White-nose syndrome is an emerging disease in North America that has caused substantial declines in hibernating bats. A recently identified fungus (Geomyces destructans) causes skin lesions that are characteristic of this disease. Typical signs of this infection were not observed in bats in North America before white-nose syndrome was detected. However, unconfirmed reports from Europe indicated white fungal growth on hibernating bats without associated deaths. To investigate these differences, hibernating bats were sampled in Germany, Switzerland, and Hungary to determine whether G. destructans is present in Europe. Microscopic observations, fungal culture, and genetic analyses of 43 samples from 23 bats indicated that 21 bats of 5 species in 3 countries were colonized by G. destructans. We hypothesize that G. destructans is present throughout Europe and that bats in Europe may be more immunologically or behaviorally resistant to G. destructans than their congeners in North America because they potentially coevolved with the fungus

Enhanced Passive Bat Rabies Surveillance in Indigenous Bat Species from Germany - A Retrospective Study

<div><p>In Germany, rabies in bats is a notifiable zoonotic disease, which is caused by European bat lyssaviruses type 1 and 2 (EBLV-1 and 2), and the recently discovered new lyssavirus species Bokeloh bat lyssavirus (BBLV). As the understanding of bat rabies in insectivorous bat species is limited, in addition to routine bat rabies diagnosis, an enhanced passive surveillance study, i.e. the retrospective investigation of dead bats that had not been tested for rabies, was initiated in 1998 to study the distribution, abundance and epidemiology of lyssavirus infections in bats from Germany. A total number of 5478 individuals representing 21 bat species within two families were included in this study. The Noctule bat (<i>Nyctalus noctula</i>) and the Common pipistrelle (<i>Pipistrellus pipistrellus</i>) represented the most specimens submitted. Of all investigated bats, 1.17% tested positive for lyssaviruses using the fluorescent antibody test (FAT). The vast majority of positive cases was identified as EBLV-1, predominately associated with the Serotine bat (<i>Eptesicus serotinus</i>). However, rabies cases in other species, i.e. Nathusius' pipistrelle bat (<i>Pipistrellus nathusii</i>), <i>P. pipistrellus</i> and Brown long-eared bat (<i>Plecotus auritus</i>) were also characterized as EBLV-1. In contrast, EBLV-2 was isolated from three Daubenton's bats (<i>Myotis daubentonii</i>). These three cases contribute significantly to the understanding of EBLV-2 infections in Germany as only one case had been reported prior to this study. This enhanced passive surveillance indicated that besides known reservoir species, further bat species are affected by lyssavirus infections. Given the increasing diversity of lyssaviruses and bats as reservoir host species worldwide, lyssavirus positive specimens, i.e. both bat and virus need to be confirmed by molecular techniques.</p></div

Map showing federal states of Germany (a) and geographical origin of all bat specimens coming from Schleswig-Holstein (SH, N = 362); Bremen (HB, N = 4), Hamburg (HH, N = 10), Mecklenburg-Western Pomerania (MWP, N = 131), Lower Saxony (LS, N = 1252), Berlin (B, N = 484), Brandenburg (BRB, N = 644), Saxony-Anhalt (ST, N = 692), Saxony (SN, N = 247), North Rhine Westphalia (NRW, N = 76), Hesse (HE, N = 89), Thuringia (TH, N = 296), Rhineland-Palatinate (RP, N = 108), Saarland (SL, N = 53), Baden-Wuerttemberg (BW, N = 736), Bavaria (BY, N = 252) (b) and of <i>E. serotinus</i> (c) collected in the study described here, and of the bat rabies cases (dot (N = 46): <i>E. serotinus</i>, triangle (N = 3): <i>M. daubentonii</i>, square (N = 3): <i>P. pipistrellus, P. nathusii and Pl. auritus</i> (d).

<p>Map showing federal states of Germany (a) and geographical origin of all bat specimens coming from Schleswig-Holstein (SH, N = 362); Bremen (HB, N = 4), Hamburg (HH, N = 10), Mecklenburg-Western Pomerania (MWP, N = 131), Lower Saxony (LS, N = 1252), Berlin (B, N = 484), Brandenburg (BRB, N = 644), Saxony-Anhalt (ST, N = 692), Saxony (SN, N = 247), North Rhine Westphalia (NRW, N = 76), Hesse (HE, N = 89), Thuringia (TH, N = 296), Rhineland-Palatinate (RP, N = 108), Saarland (SL, N = 53), Baden-Wuerttemberg (BW, N = 736), Bavaria (BY, N = 252) (b) and of <i>E. serotinus</i> (c) collected in the study described here, and of the bat rabies cases (dot (N = 46): <i>E. serotinus</i>, triangle (N = 3): <i>M. daubentonii</i>, square (N = 3): <i>P. pipistrellus, P. nathusii and Pl. auritus</i> (d).</p

Number of bat specimens tested (N = 3714, black) and rabies cases (N = 46, grey) per month during 1998 until June 2013.

<p>Number of bat specimens tested (N = 3714, black) and rabies cases (N = 46, grey) per month during 1998 until June 2013.</p

Number of bat samples per species investigated using FAT, RTCIT, RT-qPCR and RT-PCR.

<p>Number of bat samples per species investigated using FAT, RTCIT, RT-qPCR and RT-PCR.</p

Evolutionary relationships of EBLV-1 (a) and EBLV-2 strains (b) with a focus on 400 nucleotides long N-gene sequences (nt positions 1–400, numbering according to EF157976) derived from this study (boldface).

<p>The Neighbor-Joining method (p-distance, 1000 pseudoreplicates) as implemented in MEGA 5 was used. Sequence number 998 LS represents the identical sequences 959, 5300, 5304, 7471, 7467, 11647, 15730, 16902, 16908, 18720, 21836, 24525, 24529, 24832, 25495, 31054.</p