DNA-based detection of the fungal pathogen Geomyces destructans in soils from bat hibernacula

White-nose syndrome (WNS) is an emerging disease causing unprecedented morbidity and mortality among bats in eastern North America. The disease is characterized by cutaneous infection of hibernating bats by the psychrophilic fungus Geomyces destructans. Detection of G. destructans in environments occupied by bats will be critical for WNS surveillance, management and characterization of the fungal lifecycle. We initiated an rRNA gene region-based molecular survey to characterize the distribution of G. destructans in soil samples collected from bat hibernacula in the eastern United States with an existing PCR test. Although this test did not specifically detect G. destructans in soil samples based on a presence/absence metric, it did favor amplification of DNA from putative Geomyces species. Cloning and sequencing of PCR products amplified from 24 soil samples revealed 74 unique sequence variants representing 12 clades. Clones with exact sequence matches to G. destructans were identified in three of 19 soil samples from hibernacula in states where WNS is known to occur. Geomyces destructans was not identified in an additional five samples collected outside the region where WNS has been documented. This study highlights the diversity of putative Geomyces spp. in soil from bat hibernacula and indicates that further research is needed to better define the taxonomy of this genus and to develop enhanced diagnostic tests for rapid and specific detection of G. destructans in environmental samples.     

Hibernacula microclimate and declines in overwintering bats during an outbreak of white‐nose syndrome near the northern range limit of infection in North America

We document white‐nose syndrome (WNS), a lethal disease of bats caused by the fungus Pseudogymnoascus destructans (Pd), and hibernacula microclimate in New Brunswick, Canada. Our study area represents a more northern region than is common for hibernacula microclimate investigations, providing insight as to how WNS may impact bats at higher latitudes. To determine the impact of the March 2011 arrival of Pd in New Brunswick and the role of hibernacula microclimate on overwintering bat mortality, we surveyed bat numbers at hibernacula twice a year from 2009 to 2015. We also collected data from iButton temperature loggers deployed at all sites and data from HOBO temperature and humidity loggers at three sites. Bat species found in New Brunswick hibernacula include Myotis lucifugus (Little Brown Bat) and M. septentrionalis (Northern Long‐eared Bat), with small numbers of Perimyotis subflavus (Tricolored Bat). All known hibernacula in the province were Pd‐positive with WNS‐positive bats by winter 2013. A 99% decrease in the overwintering bat population in New Brunswick was observed between 2011 and 2015. We did not observe P. subflavus during surveys 2013–2015 and the species appears to be extirpated from these sites. Bats did not appear to choose hibernacula based on winter temperatures, but dark zone (zone where no light penetrates) winter temperatures did not differ among our study sites. Winter dark zone temperatures were warmer and less variable than entrance or above ground temperatures. We observed visible Pd growth on hibernating bats in New Brunswick during early winter surveys (November), even though hibernacula temperatures were colder than optimum for in vitro Pd growth. This suggests that cold hibernacula temperatures encountered near the apparent northern range limit for Pd do not sufficiently slow fungal growth to prevent the onset of WNS and associated bat mortality over the winter.     

Going, going, gone: the impact of white-nose syndrome on the summer activity of the little brown bat (Myotis lucifugus)

Since its discovery in the winter of 2005-2006, white-nose syndrome (WNS) has killed over one million little brown bats (Myotis lucifugus) in the American northeast. Although many studies have reported die-offs of bats at winter hibernacula, it is important to understand how bat mortality linked to WNS at winter hibernacula affects bat activity levels in their summer ranges. In the summer (May-August) of 2007, 2008 and 2009, we recorded echolocation calls to determine bat activity at sites along the Hudson River, NY (within approx. 100 km of where WNS was first reported). We documented a 78 per cent decline in the summer activity of M. lucifugus, coinciding with the arrival and spread of WNS. We suggest that mortality of M. lucifugus in winter hibernacula is reflected by reduced levels of activity in the summer and that WNS affects the entire bat population of an area, and not only individual hibernacula.     

Emergence activity at hibernacula differs among four bat species affected by white‐nose syndrome

Prior to the introduction of white‐nose syndrome (WNS) to North America, temperate bats were thought to remain within hibernacula throughout most of the winter. However, recent research has shown that bats in the southeastern United States emerge regularly from hibernation and are active on the landscape, regardless of their WNS status. The relationship between winter activity and susceptibility to WNS has yet to be explored but warrants attention, as it may enable managers to implement targeted management for WNS‐affected species. We investigated this relationship by implanting 1346 passive integrated transponder (PIT) tags in four species that vary in their susceptibility to WNS. Based on PIT‐tag detections, three species entered hibernation from late October to early November. Bats were active at hibernacula entrances on days when midpoint temperatures ranged from −1.94 to 22.78°C (mean midpoint temperature = 8.70 ± 0.33°C). Eastern small‐footed bats (Myotis leibii), a species with low susceptibility to WNS, were active throughout winter, with a significant decrease in activity in mid‐hibernation (December 16 to February 15). Tricolored bats (Perimyotis subflavus), a species that is highly susceptible to WNS, exhibited an increase in activity beginning in mid‐hibernation and extending through late hibernation (February 16 to March 31). Indiana bats (M. sodalis), a species determined to have a medium–high susceptibility to WNS, remained on the landscape into early hibernation (November 1 to December 15), after which we did not record any again until the latter portion of mid‐hibernation. Finally, gray bats (M. grisescens), another species with low susceptibility to WNS, maintained low but regular levels of activity throughout winter. Given these results, we determined that emergence activity from hibernacula during winter is highly variable among bat species and our data will assist wildlife managers to make informed decisions regarding the timing of implementation of species‐specific conservation actions.     

The distribution of the Greater horse-shoe bat, Rhinolophus ferrum-equinum, during hibernation, in relation to environmental factors

Hibernation is a vital factor in the ability of bats to survive in temperate countries where insect availability is drastically reduced in winter. The value of hibernation in survival lies in the reduction of the bat's metabolic rate to very low levels, thus reducing their food requirements.
The selection of a site which fulfils the physiological requirements of hibernation must be important in the survival of the Greater horse-shoe bat. The present study shows that temperature is particularly important in the selection of a precise position for hibernation. The temperature required, however, varies throughout the winter.
In England this bat finds suitable conditions in caves, mines, tunnels, cellars, and house attics. All are dark where the bats are found and offer protection from predators. These considerations are not sufficient to explain the distribution of this bat in hibernation.
The present study shows that a large proportion of the population feeds outside the hibernaculum at times during the hibernation period. The evidence suggests that starvation is a cause of death. Hence it is not only the conditions inside the hibernacula which are important in the winter survival of a bat population. The environmental conditions outside may be just as vital.
The Greater horse-shoe bat is vulnerable since the bulk of its population depends upon relatively few sites. Its reproductive rate is very low and active conservation is needed in England, since populations are small. If conservation is to be successful however, both the physical conditions within hibernacula, and the environmental conditions outside will have to be satisfactory.     

河南济源人工引水渠隧道蝙蝠冬眠生态学特征

2017-2020年期间,每年1月份对河南省济源市邵原镇布袋沟水库人工引水渠隧道内蝙蝠进行冬眠生态学特征调查,共发现2科5属7种蝙蝠在此冬眠,包括马铁菊头蝠（Rhinolophus ferrumequinum）、小菊头蝠（R.pusillus）、华南水鼠耳蝠（Myotis laniger）、白腹管鼻蝠（Murina leucogaster）、金管鼻蝠（Mu.aurata）、奥氏长耳蝠（Plecotus ognevi）和亚洲宽耳蝠（Barbastella leucomelas）。马铁菊头蝠是优势种（约52%-73%的冬眠个体）,其次是小菊头蝠（约19%-37%）、华南水鼠耳蝠（约5%-8%）,其余蝙蝠物种数量不足3%。2017-2020年冬眠蝙蝠个体总数呈增长趋势,但仍少于早期报道的数量。有42个隧道每年均有蝙蝠冬眠,而且不同年度冬眠数量也不尽相同。通过多元线性回归分析发现,隧道长度可能是影响蝙蝠冬眠栖息场所选择的主要影响因子（Adjusted R²=0.208,P=0.001）。每个隧道内,蝙蝠具有不同的冬眠栖点位置,约4/5的蝙蝠选择温暖且环境相对稳定的隧道深处（> 30 m）作为冬眠栖点,超过95%的个体选择长度> 60 m的隧道冬眠。蝙蝠具有不同的冬眠方式,绝大多数个体采用独栖方式进行冬眠（> 90%）,少数采用聚集方式。不同的冬眠栖点和冬眠方式可能有利于冬眠成本优化。此外,栖点温度与蝙蝠体温之间呈显著正相关（R²=0.98,P < 0.001）,而且蝙蝠冬眠期间的栖点温度具有种内和种间差异。研究结果为我国蝙蝠种群保护和冬眠场所管理提供科学依据。     

Subtropical mouse-tailed bats use geothermally heated caves for winter hibernation

We report that two species of mouse-tailed bats (Rhinopoma microphyllum and R. cystops) hibernate for five months during winter in geothermally heated caves with stable high temperature (20°C). While hibernating, these bats do not feed or drink, even on warm nights when other bat species are active. We used thermo-sensitive transmitters to measure the bats’ skin temperature in the natural hibernacula and open flow respirometry to measure torpid metabolic rate at different ambient temperatures (T_a, 16–35°C) and evaporative water loss (EWL) in the laboratory. Bats average skin temperature at the natural hibernacula was 21.7 ± 0.8°C, and no arousals were recorded. Both species reached the lowest metabolic rates around natural hibernacula temperatures (20°C, average of 0.14 ± 0.01 and 0.16 ± 0.04 ml O₂ g⁻¹ h⁻¹ for R. microphyllum and R. cystops, respectively) and aroused from torpor when T_a fell below 16°C. During torpor the bats performed long apnoeas (14 ± 1.6 and 16 ± 1.5 min, respectively) and had a very low EWL. We hypothesize that the particular diet of these bats is an adaptation to hibernation at high temperatures and that caves featuring high temperature and humidity during winter enable these species to survive this season on the northern edge of their world distribution.     

The trans-boundary importance of artificial bat hibernacula in managed European forests

Many European migratory bat species hibernate in large hollow trees, a decreasing resource in present day silviculture. Here, we report on the importance of man-made hibernacula to support trans-boundary populations of noctule bats (Nyctalus noctula), a species that performs seasonal long distance movements throughout Europe. In winter, we surveyed nine bat roosts (eight artificial and one natural) in Germany and collected small tufts of fur from a total of 608 individuals. We then measured the stable isotope ratios of the non-exchangeable hydrogen in fur keratin and estimated the origin of migrants using a refined isoscape origin model that included information on expected flight distances and migration directions. According to the stable isotope signature, 78 % of hibernating bats originated from local populations. The remaining 22 % of hibernacula occupants originated from distant populations, mostly from places in northern or eastern countries such as Sweden, Poland and Baltic countries. Our results confirm that many noctule bats cross one or several political borders during migration. Data on the breeding origin of hibernating noctule bats also suggest that artificial roosts may not only be important for local but also for distant populations. Protection of natural and artificial hibernacula in managed forests may support the trans-boundary populations of migratory bats when hollow trees are scarce in managed forests.     

Hibernation in warm hibernacula by free-ranging Formosan leaf-nosed bats, <Emphasis Type="Italic">Hipposideros terasensis</Emphasis>, in subtropical Taiwan

The subtropical Formosan leaf-nosed bats, Hipposideros terasensis (Hipposideridae), show little activity during winter. It has never been determined whether in winter they exhibit hibernation and multi-day periods of low body temperature. The objectives of this study were to understand the winter activity pattern of H. terasensis and to examine whether it enters hibernation during winter. We monitored the skin temperature (T _sk) of nine free-ranging H. terasensis by attaching temperature-sensitive transmitters during the winters of 2007–2008 and 2008–2009. The results showed that H. terasensis entered hibernation from late December to early March. H. terasensis, however, differs from temperate hibernating bats in several ways: (1) it is capable of hibernation at roost temperature (T _r) and T _sk > 20°C; (2) hibernation at high T _r and T _sk does not lead to a relatively high arousal frequency; and (3) adults do not increase body mass in autumn prior to hibernation. To test the hypothesis that H. terasensis feeds frequently during the hibernation period to compensate for the high energetic demands of hibernating in warm hibernacula, we recorded the number and timing of bats that emerged from and entered into a hibernaculum, which contained more than 1,000 bats. From 30 December 2007 to 29 February 2008, an average of only 8.4 bats (<1%) per night (29 nights) emerged from the hibernaculum. Adult bats lost an average of 13–14% of body mass during an approximately 70-day hibernation period. We suggest that H. terasensis might have remarkably low torpid metabolic rates during hibernation.     

A decade of hibernating bat communities along the periphery of a region of white-nose syndrome

Long-term monitoring programs are necessary to assess populations for conservation planning and management decisions. Hibernating bats in North America have declined because of numerous natural and human-induced disturbances. White-nose syndrome (WNS) has become the most serious threat to North American cave-dwelling bats, leading to significant population declines in several species. We examined trends in hibernating bat populations at 11 hibernacula in northern Georgia and Alabama, USA, from 2013–2022, beginning when WNS was first detected in the region. Although we observed interannual variation in numbers of the federally endangered gray bat (Myotis grisescens), mean counts remained stable over time. In contrast, the tricolored bat (Perimyotis subflavus) and the federally endangered northern long-eared bat (M. septentrionalis) declined by >90% in the first 5 years after WNS detection in the region. Although no northern long-eared bats have been reported since 2019, tricolored bat counts stabilized following initial declines. Understanding changes in bat populations as WNS continues to spread, and determining the extent of population declines, is necessary for making appropriate management decisions. Our findings elucidate the status of cave-dwelling bat species along the periphery of the white-nose syndrome endemic region and highlight the importance of monitoring bat communities on a regional scale to develop effective conservation strategies.     

Declines in summer bat activity in central New England 4 years following the initial detection of white-nose syndrome

White-nose syndrome (WNS) was first reported in a hibernating bat population in central New York State in February 2006. Since 2006, WNS has been reported from bat hibernacula across much of eastern United States and adjacent Canada and has been associated with a dramatic decline in the populations of hibernating bats in the northeastern U.S. We are only beginning to discover how these declines are manifest in changes in summer bat abundance and activity at local scales. A 3-year (2004–2006) acoustic survey showed that the forested watershed of the Quabbin Reservoir in central Massachusetts supported an abundant and species-rich summer bat community. In 2010, 4-years following the initial occurrence of WNS, a re-survey of the same habitats and sites found a 72% reduction in bat activity on the watershed. This is the identical rate of decline reported from cave hibernacula surveys (73%). This decline in summer activity levels is most likely a consequence of WNS-caused mortality. The impacts of population losses of this magnitude of a once widespread and abundant taxa are unknown but are presumed to be ecologically significant.     

Hibernacula selection by Townsend's big-Eared bat in southwestern Colorado

In western United States, both mine reclamations and renewed mining at previously abandoned mines have increased substantially in the last decade. This increased activity may adversely impact bats that use these mines for roosting. Townsend's big-eared bat (Corynorhinus townsendii) is a species of conservation concern that may be impacted by ongoing mine reclamation and renewed mineral extraction. To help inform wildlife management decisions related to bat use of abandoned mine sites, we used logistic regression, Akaike's information criterion, and multi-model inference to investigate hibernacula use by Townsend's big-eared bats using 9 years of data from surveys inside abandoned mines in southwestern Colorado. Townsend's big-eared bats were found in 38 of 133 mines surveyed (29%), and occupied mines averaged 2.6 individuals per mine. The model explaining the most variability in our data included number of openings and portal temperature at abandoned mines. In southwestern Colorado, we found that abandoned mine sites with more than one opening and portal temperatures near 0°C were more likely to contain hibernating Townsend's big-eared bats. However, mines with only one opening and portal temperatures of ≥10°C were occasionally occupied by Townsend's big-eared bat. Understanding mine use by Townsend's big-eared bat can help guide decisions regarding allocation of resources and placement of bat-compatible closures at mine sites scheduled for reclamation. When feasible we believe that surveys should be conducted inside all abandoned mines in a reclamation project at least once during winter prior to making closure and reclamation recommendations. © 2010 The Wildlife Society.     

Changes in abundance of hibernating bats in central Slovakia (1992–2009)

An analysis of long-term changes in abundance of hibernating bats as revealed from the annual monitoring programme conducted in four mountain regions of the Western Carpathians (Muránska planina Mts, Revúcka vrchovina Mts, Slovensky kras Mts, Štiavnické vrchy Mts) during the period 1992–2009 is providing in the paper. Data from 52 hibernacula were analysed. Among 18 bat species recorded, an apparent population increase of three most abundant thermophilous and originally cave dwelling species of bats, Rhinolophus hipposideros, R. ferrumequinum, Myotis myotis, was observed. In other bat species (e.g., R. euryale, M. emarginatus, M. mystacinus, M. dasycneme, Barbastella barbastellus), population trends could not be detected and because of data scarcity, they should be evaluated from more extensive datasets obtained from a wide range of hibernacula or from a completely different type of evidence.     

Predation of wood mice (Apodemus sylvaticus) on hibernating bats

Bat hibernacula with high numbers of bats can become high-risk areas, as they attract flying and non-flying predators. In order to protect hibernating bats effectively, more knowledge about mortality factors is needed. During the winters of 2003–2015, we found 214 dead bats in 12 hibernacula in The Netherlands province of Zuid-Holland. Most bat remains were found in December and January, with a second peak in April. Their remains showed a typical pattern of lesions consistent with those caused by predation by the wood mouse (Apodemus sylvaticus). Trail camera surveys showed that wood mice actively searched for bats. Predation pressure seemed to vary between winters, with a peak in the winters of 2004, 2011 and 2015. The annual mortality (relative to the maximum winter population size) caused by wood mouse predation varied between 0.1 and 8.8 %, with a maximum local effect of 83.6 %. The years with high wood mouse predation pressure were characterized by a long frost period and a low mast production of common oak in the preceding autumn. The size of a hibernaculum and the population density of its bats had an effect on predation-dependent mortality. The highest predation risk occurred near the entrance of bunkers. From these results we tentatively conclude that predation is not incidental and that wood mice actively search for and kill hibernating bats or scavenge for weakened individuals.     

Influences of Landscape Features on Bat Activity in North Dakota

Land conversion and modification threatens many wildlife and plant species in the northern Great Plains, including bats. Our objective was to assess the association of bat species with landscape features in the northern Great Plains of North Dakota, USA, taking the first step towards understanding the habitat needs of bats in this region. We examined patterns of bat activity across different landscapes, identified those landscape features associated with high levels of bat activity, and determined which specific land features (i.e., vegetation and water types) were most commonly associated with each bat species. We used passive acoustic monitoring to measure bat activity at sites across North Dakota, and assessed detailed land characteristics at each site. We used nonmetric multidimensional scaling and multivariate regression tree analysis to examine relationships between bat activity and landscape variables. Bat foraging activity was influenced by structural landscape characteristics and the availability of specific water resources. High levels of bat activity were associated with riparian forested areas of varying structural complexity, ponds, and, to a lesser extent, open riparian lands. Individual bat species were influenced by land type and water resources differently. We identified big brown bats (Eptesicus fuscus) and little brown bats (Myotis lucifugus) as indicators of open riparian and pond landscapes, respectively. These results highlight the importance of prairie riparian landscapes and maintaining heterogeneity across the landscape for conservation and management of bat communities. Further, we identified ponds as an important landscape feature for little brown bats, a species of conservation concern, indicating that this specific feature should be a focus of conservation efforts on prairie wetlands. © 2019 The Wildlife Society.     

Effectiveness of an acoustic lure for surveying bats in British woodlands

1. A field experiment was used to test the effectiveness of a synthesized bat call as an acoustic lure to attract bats into mist nets in woodlands in southeast England. The stimulus was modelled on a social call of the rare Bechstein's bat Myotis bechsteinii. 2. In the Test condition, when the synthesized call was played, 23 bats of four species were captured, including six Bechstein's bats. In the Control condition, when no calls were played, only one bat was caught. 3. The bat call synthesizer is an effective tool for increasing capture rates for bats. Used as part of a systematic survey programme, it has the potential to provide the first baseline data on the distribution of bats in British woodlands.     

Habitat Use,Roost Selection and Conservation of Bats in Tsingy De Bemaraha National Park,Madagascar

Although the land mammals of Madagascar have been the subject of many studies, the island’s bats have yet to feature prominently on the research or conservation agenda. In this study we used mist nets, acoustic sampling and cave surveys to assess habitat use, seasonality and roost selection. Four microchiropteran species (Triaenops rufus, T. furculus, Miniopterus manavi and Myotis goudoti) appeared to be strongly associated with the forest interior based on trapping, but analysis of time-expanded echolocation recordings revealed that T. rufus and M.␣manavi were frequently recorded in forest edges and clearings. Bat activity was significantly lower inside the forest than at the interface between agricultural land and forest. The caves visited most often by tourists were low in bat abundance and species richness. Anjohikinakina Cave, which was visited infrequently by people, was used by five species and contained between 54% (winter) and 99% (summer) of bats counted in 16 caves and is a site of national importance for bat conservation. Hipposideros commersoni was only netted in our study area during October and may be a migrant to the site or present but inactive during the austral winter. The forest surrounding the caves is therefore important because it provides cover for emerging bats and a potential source of invertebrate prey whilst the forest edge is important to foraging bats.     

Long‐term changes in bat activity in Quebec suggest climatic responses and summer niche partitioning associated with white‐nose syndrome

In North America, the greatest and most sudden threat to hibernating bats is white‐nose syndrome (WNS), which has caused massive declines in populations since 2006. Other determinants of bat dynamics, such as the climate, and the effect of reduction in the number of individuals sharing foraging space and summer roosting habitat may have an effect on population dynamics. We analyzed transect acoustic bat surveys conducted with ultrasonic detectors in 16 regions in Quebec, Canada, between 2000 and 2015. We used piecewise regression to describe changes in activity over time for each species and a meta‐analytic approach to measure its association with the North Atlantic Oscillation (NAO). As expected, mouse‐eared bat (Myotis spp.) activity sharply declined after the onset of WNS, down by 79% after 3 years. In contrast, big brown/silver‐haired bat activity increased over the same period, possibly due to a release of competition. Hoary bats and red bats remained present, although their activity did not increase. Myotis activity was positively correlated with a one‐year lag to the NAO index, associated with cold conditions in winter, but warm autumns. Big brown/silver‐haired and hoary bats were also more active during NAO‐positive years but without a lag. We conclude that combinations of threats may create rapid shifts in community compositions and that a more balanced research agenda that integrates a wider range of threats would help better understand and manage those changes.     

Seasonal Shifts in Nocturnal Habitat Use by Coastal Bat Species

Sensitivity of bats to land use change depends on their foraging ecology, which varies among species based on ecomorphological traits. Additionally, because prey availability, vegetative clutter, and temperature change throughout the year, some species may display seasonal shifts in their nocturnal habitat use. In the Coastal Plain of South Carolina, USA, the northern long-eared bat (Myotis septentrionalis), southeastern myotis (Myotis austroriparius), tri-colored bat (Perimyotis subflavus), and northern yellow bat (Lasiurus intermedius) are species of conservation concern that are threatened by habitat loss. Our objective was to identify characteristics of habitat used by these species during their nightly active period and compare use between summer and winter. We conducted acoustic surveys at 125 sites during May–August and at 121 of the same 125 sites December–March 2018 and 2019 in upland forests, bottomland forests, fields, ponds, and salt marsh and used occupancy models to assess habitat use. The northern long-eared bat and southeastern myotis (i.e., myotis bats) used sites that were closer to hardwood stands, pine stands, and fresh water year-round. We did not identify any strong predictors of tri-colored bat habitat use in summer, but during winter they used bottomland forests, fields, and ponds more than salt marsh and upland forests. During summer and winter, northern yellow bats used sites close to fresh water and salt marsh. Additionally, during summer they used fields, ponds, and salt marsh more than upland and bottomland forests, but in winter they used bottomland forests, fields, and ponds more than upland forest and salt marsh. Our results highlight important land cover types for bats in this area (e.g., bottomland forests, ponds, and salt marsh), and that habitat use changes between seasons. Accounting for and understanding how habitat use changes throughout the year will inform managers about how critical habitat features may vary in their importance to bats throughout the year. © 2021 The Wildlife Society.     

Recovery of little brown bats (Myotis lucifugus) from natural infection with Geomyces destructans, white-nose syndrome

Geomyces destructans produces the white fungal growth on the muzzle and the tacky white discoloration on wings and ears that characterize white-nose syndrome (WNS) in cave-hibernating bats. To test the hypothesis that postemergent WNS-infected bats recover from infection with G. destructans, 30 little brown bats (Myotis lucifugus) were collected in May 2009 from a WNS-affected hibernation site in New Jersey. All bats were confirmed to be infected with G. destructans using a noninvasive fungal tape method to identify the conidia of G. destructans and polymerase chain reaction (PCR). The bats were then held in captivity and given supportive care for 70 days. Of the 26 bats that survived and were humanely killed after 70 days, 25 showed significant improvement in the external appearance of wing membranes, had no microscopic evidence of infection by G. destructans, and had wing tissue samples that were negative for G. destructans by PCR. A subset of the bats was treated topically at the beginning of the rehabilitation study with a dilute vinegar solution, but treatment with vinegar provided no added advantage to recovery. Provision of supportive care to homeothermic bats was sufficient for full recovery from WNS. One bat at day 70 still had both gross pathology and microscopic evidence of WNS in wing membranes and was PCR-positive for G. destructans. Dense aggregates of neutrophils surrounded the hyphae that remained in the wing membrane of this bat.