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Rapid evolution of advantageous traits following abrupt environmental change can help populations recover from demographic decline. However, for many introduced diseases affecting longer-lived, slower reproducing hosts, mortality is likely to outpace the acquisition of adaptive de novo mutations. Adaptive alleles must therefore be selected from standing genetic variation, a process that leaves few detectable genomic signatures. Here, we present whole genome evidence for selection in bat populations that are recovering from white-nose syndrome (WNS). We collected samples both during and after a WNS-induced mass mortality event in two little brown bat populations that are beginning to show signs of recovery and found signatures of soft sweeps from standing genetic variation at multiple loci throughout the genome. We identified one locus putatively under selection in a gene associated with the immune system. Multiple loci putatively under selection were located within genes previously linked to host response to WNS as well as to changes in metabolism during hibernation. Results from two additional populations suggested that loci under selection may differ somewhat among populations. Through these findings, we suggest that WNS-induced selection may contribute to genetic resistance in this slowly reproducing species threatened with extinction.

Understanding why private property owners take actions to conserve bats has become increasingly important in U.S. states where the fungus causing white-nose syndrome (Pseudogymnoascus destructans) has decimated bat populations. We surveyed property owners in three New York State counties (n = 2,500) and used multiple linear regression analyses to test predictors of intentions to conserve bats. Intentions to take actions that contribute to bat conservation directly were predicted by severity of rabies consequences, sense of bat conservation self efficacy, beliefs about responsibility for bat conservation, and attitudes toward bats (R² =.39). Intentions to take actions that conserve bats indirectly were predicted by biospheric value orientations, beliefs about responsibility for bat conservation, and attitudes toward bats (R² =.27). The relationship between beliefs about rabies and intentions to take actions that contribute to bat conservation highlights the need for coordinated risk communication between public health and wildlife conservation organizations.

Emerging infectious diseases have resulted in severe population declines across diverse taxa. In some instances, despite attributes associated with high extinction risk, disease emergence and host declines are followed by host stabilization for reasons that are frequently unclear. While host, pathogen, and the environment are recognized as important factors that interact to determine host-pathogen coexistence, they are often considered independently. Here, we use a translocation experiment to disentangle the role of host traits and environmental conditions in driving the persistence of remnant populations a decade after they declined 70-99% and subsequently stabilized with disease. While survival was significantly higher than during the initial epidemic within all sites, protection from severe disease only existed within a narrow environmental space, suggesting host traits conducive to surviving disease are highly environmentally dependent. Ultimately, population persistence following pathogen invasion is the product of host-pathogen interactions that vary across a patchwork of environments.

Assessing the scope and severity of threats is necessary for evaluating impacts on populations to inform conservation planning. Quantitative threat assessment often requires monitoring programs that provide reliable data over relevant spatial and temporal scales, yet such programs can be difficult to justify until there is an apparent stressor. Leveraging efforts of wildlife management agencies to record winter counts of hibernating bats, we collated data for 5 species from over 200 sites across 27 U.S. states and 2 Canadian provinces from 1995 to 2018 to determine the impact of white‐nose syndrome (WNS), a deadly disease of hibernating bats. We estimated declines of winter counts of bat colonies at sites where the invasive fungus that causes WNS (Pseudogymnoascus destructans) had been detected to assess the threat impact of WNS. Three species undergoing species status assessment by the U.S. Fish and Wildlife Service (Myotis septentrionalis, Myotis lucifugus, and Perimyotis subflavus) declined by more than 90%, which warrants classifying the severity of the WNS threat as extreme based on criteria used by NatureServe. The scope of the WNS threat as defined by NatureServe criteria was large (36% of Myotis lucifugus range) to pervasive (79% of Myotis septentrionalis range) for these species. Declines for 2 other species (Myotis sodalis and Eptesicus fuscus) were less severe but still qualified as moderate to serious based on NatureServe criteria. Data‐sharing across jurisdictions provided a comprehensive evaluation of scope and severity of the threat of WNS and indicated regional differences that can inform response efforts at international, national, and state or provincial jurisdictions. We assessed the threat impact of an emerging infectious disease by uniting monitoring efforts across jurisdictional boundaries and demonstrated the importance of coordinated monitoring programs, such as the North American Bat Monitoring Program (NABat), for data‐driven conservation assessments and planning., Article impact statement: Data sharing and coordinated monitoring are needed to assess species’ response to threats to inform conservation planning at relevant scales.

Novel pathogens can cause massive declines in populations, and even extirpation of hosts. But disease can also act as a selective pressure on survivors, driving the evolution of resistance or tolerance. Bat white-nose syndrome (WNS) is a rapidly spreading wildlife disease in North America. The fungus causing the disease invades skin tissues of hibernating bats, resulting in disruption of hibernation behavior, premature energy depletion, and subsequent death. We used whole-genome sequencing to investigate changes in allele frequencies within a population of Myotis lucifugus in eastern North America to search for genetic resistance to WNS. Our results show low FST values within the population across time, i.e., prior to WNS (Pre-WNS) compared to the population that has survived WNS (Post-WNS). However, when dividing the population with a geographical cut-off between the states of Pennsylvania and New York, a sharp increase in values on scaffold GL429776 is evident in the Post-WNS samples. Genes present in the diverged area are associated with thermoregulation and promotion of brown fat production. Thus, although WNS may not have subjected the entire M. lucifugus population to selective pressure, it may have selected for specific alleles in Pennsylvania through decreased gene flow within the population. However, the persistence of remnant sub-populations in the aftermath of WNS is likely due to multiple factors in bat life history.

Background White-nose Syndrome (WNS) is a mycosis caused by a cutaneous infection with the fungus Pseudogymnoascus destructans (Pd). It produces hibernation mortality rates of 75–98% in 4 bats: Myotis lucifugus, M. septentrionalis, M. sodalis, and Perimyotis subflavus. These high mortality rates were observed during the first several years after the arrival of P. destructans at a hibernation site. Mortality is caused by a 60% decrease in torpor bout duration, which results in a premature depletion of depot fat prior to spring. Results Little is known about the long-term effects of Pd on torpor and mortality, thus we conducted a 9-year study on M. lucifugus at 5 of the hibernation sites where Pd first appeared in North America during the winter of 2007–08. The M. lucifugus hibernating at one of these sites one year after the arrival of Pd (2008–09) had: a) a mean torpor bout duration of 7.6 d, b) no depot fat reserves by March, and c) an apparent over-winter mortality rate of 88%. The M. lucifugus hibernating at this same site 6–9 years after the arrival of Pd, in contrast, had: a) a mean torpor bout duration of 14.7 d, b) depot fat remaining in March, and c) an apparent mortality rate of 50%. The number of M. lucifugus hibernating at 2 of these sites has consistently increased since 2010 and is now more than 3.0-fold higher than the number remaining after the winter of 2008–09. Conclusions These findings indicate that this population of M. lucifugus has evolved mechanisms to hibernate well in the presence of Pd, thus reducing over-winter mortality.

Rapid evolution of advantageous traits following abrupt environmental change can help populations grow and avoid extinction through evolutionary rescue. Here, we provide the first genetic evidence for rapid evolution in bat populations affected by white-nose syndrome (WNS). By comparing genetic samples from before and after little brown bat populations were decimated by WNS, we identified signatures of soft selection on standing genetic variation. This selection occurred at multiple loci in genes linked to hibernation behavior rather than immune function, suggesting that differences in hibernation strategy have allowed these bats to survive infection with WNS. Through these findings, we suggest that evolutionary rescue can be a conservationrelevant process even in slowly reproducing taxa threatened with extinction.

White Nose Syndrome (WNS) greatly increases the over-winter mortality of little brown (Myotis lucifugus), Indiana (Myotis sodalis), northern (Myotis septentrionalis), and tricolored (Perimyotis subflavus) bats. It is caused by a cutaneous infection with the fungus Pseudogymnoascus destructans (Pd). Big brown bats (Eptesicus fuscus) are much more resistant to cutaneous infection with Pd, however. We thus conducted analyses of wing epidermis from hibernating E. fuscus and M. lucifugus to determine their fatty acid compositions, and laboratory Pd culture experiments at 4.0–13.4°C to determine the effects of these fatty acids on Pd growth. Our analyses revealed that the epidermis of both bat species contain the same 7 fatty acid types (14:0, 15:0, 16:0. 16:1, 18:0, 18:1, & 18:2), but the epidermis of M. lucifugus contains: a) more stearic (18:0) acid, b) less palmitoleic (16:1) acid, c) less myristic (14:0) acid, and, d) less oleic (18:1) acid than that of E. fuscus. The growth of Pd was inhibited by: a) myristic and stearic acids at 10.5–13.4°C, but not at 4.0–5.0°C, b) oleic acid at 5.0–10.6°C, c) palmitoleic acid, and, d) linoleic (18:2) acid at 5.0–10.6°C. One set of factors that enables E. fuscus to better resist cutaneous P. destructans infections (and thus WNS) therefore appears to be the relatively higher myristic, palmitoleic, and oleic acid contents of the epidermis.

The size and distribution of measurement errors associated with major techniques for estimating numbers of hibernating bats are unstudied, although this is the principle method of enumerating several endangered bat species. However, decisions concerning the listing status of a species under the Endangered Species Act require consistent and accurate estimation of population size and trends. Recent advances in digital photography have improved the ability to produce a quantitative record of the numbers of bats in hibernacula. We surveyed clusters of Indiana bats in a hibernaculum and compared results from counts of digital photographs of clusters to results from 4 variations of visual estimation. We counted bats in photographs using Geographic Information System digitization over the photograph. Total counts from 2 sets of photographs varied by

If individuals can be identified from patterns in their footprints, noninvasive survey methods can be used to estimate abundance. Track plates capture fine detail in the footprints of fishers (Martes pennanti), recording rows of dots corresponding to tiny papillae on the animal's metacarpal pad. We show that the pattern of these dots can be used to identify individual fishers, similar to human fingerprints. A probabilistic model of uniqueness based on variation in spacing between 1,400 pairs of dots that we measured in prints of 14 different fisher feet suggests the probability of encountering a similar pattern in the print of a different foot by chance alone is