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Presence and count trends from 2003 to 2019 for bat species in the Monongahela National Forest (MNF), West Virginia, USA, that responded positively, including (a) Eptesicus fuscus (big brown bat; n = 1,311 captures), (b) Lasiurus borealis (eastern red bat; n = 1,334 captures); or showed no clear response, including (c) Corynorhinus townsendii virginianus (Virginia big‐eared bat; n = 159 captures), and (d) Myotis leibii (eastern small‐footed myotis; n = 151 captures) to invasion of white‐nose syndrome (WNS). We estimated bat trends using annual mist‐net survey data and zero‐inflated Poisson generalized additive models (ZIPGAM), with year included as a smoothed continuous predictor. At least 20 sites were surveyed annually, with two surveys per site within years. For each species, the upper graphs display the probability of presence and estimated count for occupied sites (black lines) and their 95% confidence intervals (gray bands), and the bottom graphs display the rate of change (i.e., slope of the tangent line) for the presence and count estimates. A positive slope indicates the population is increasing relative to the slope in the previous time step, and vice versa. The points on the presence trend graphs represent the annual mean proportion of sites with observed presence. The points on the count trend graphs represent the annual mean of the total count per site at observed occupied sites (note the lower bound is 1). The rectangle in each graph encompasses the years of observed spread of WNS across the MNF (2009–2011)
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White-nose syndrome (WNS) is a disease caused by the fungus Pseudogymnoascus destructans which has resulted in the deaths of millions of bats across eastern North America. To date, hibernacula counts have been the predominant means of tracking the spread and impact of this disease on bat populations. However, an understanding of the impacts of WNS...
Citations
... Our results add to the growing literature that there are there are energetic costs for reproductive-age females contending with the effects of WNS [38,57]. We observed a post-WNS decline in captures of reproductive females of WNS-susceptible species (M. ...
White-nose syndrome (WNS) is an infectious disease that disrupts hibernation in bats, leading to premature exhaustion of fat stores. Though we know WNS does impact reproduction in hibernating female bats, we are unsure how these impacts are exacerbated by local climate factors. We compiled data from four southeastern U.S. states and used generalized linear mixed effects models to compare effects of WNS, pre-hibernation climate variables, and winter duration on the number of reproductive females in species across the range of WNS susceptibility. We predicted we would see a decline in the number of reproductive females in WNS-susceptible species, with the effect exaggerated by longer winter durations and pre-hibernation climate variables that lead to reductions in foraging. We found that the number of reproductive females in WNS-susceptible species was positively correlated with pre-hibernation local climate conditions conducive to foraging; however, WNS-susceptible species experienced an overall decline with the presence of WNS and as winter duration increased. Our long-term dataset provides evidence that pre-hibernation climate, specifically favorable summer weather conditions for foraging, greatly influences the reproduction, regardless of WNS status.
... septentrionalis) populations dropped by 98% and the Tricolored Bat (Pipistrellus subflavus) by 77% (Cheng et al. 2021;Perry and Jordan 2022). The impact of WNS has primarily been assessed based on trends in population estimates derived from surveys conducted in caves during winter hibernation (e.g., Cheng et al. 2021) or from capture rates in mist nets during the summer months (e.g., Johnson et al. 2021). However, in Arkansas the Eastern Small-footed Bat has been observed in only a few caves, usually in small numbers, and is rarely observed in other surveys such as mist netting (Sasse et al. 2013) and the impact of WNS on this species in this state is unknown. ...
The Eastern Small-footed Bat (Myotis leibii) inhabits mountainous areas of the eastern United States and generally roosts in cliff faces and talus slopes. However, the difficulty of accessing these sites has limited research on this species. We studied survival rates of eastern small-footed bats by capturing bats roosting in crevices between sections of concrete guardrails on bridges in the Ozark mountains of northern Arkansas from 2014 to 2021. We accumulated 1,413 bat captures (1,050F; 363M) of 283 individual females and 198 individual males sampled
over 8 years and determined apparent annual survival of female bats using Cormack–Jolly–Seber survival models. Only 1 of 30 bats tested positive for the presence of Pseduogymnoascus destructans, a fungus causing whitenose
syndrome (WNS) which is responsible for significant declines in populations of some North American bat species, when all maternity colonies were sampled in the spring of 2019. Overall apparent annual survival of all females was 0.643, with first-year juvenile survival of 0.472 and adult (ages 1–6) survival of 0.744, approximately
58% greater than first-year survival. Apparent annual survival did not differ greatly among the sites or among years. We found no significant decline or increase in overall number of bats among all sites during the 8 years of study. Stability in both the number of bats encountered and their survival rates suggests that the impact
of WNS on these colonies has been marginal.
... Bats in hibernacula infected with WNS have more activity than noninfected hibernacula, including flights over the landscape in cooler temperatures (Bernard and McCracken, 2017). In addition to observed fatalities at hibernacula, WNS has also been linked to decreased regional populations (Turner et al., 2011;Ingersoll et al., 2013;Ingersoll et al., 2016;Perry and Jordan, 2022), cave-bat abundance in summer habitats (Dzal et al., 2010;Brooks, 2011;O'Keefe et al., 2019, Deeley et al., 2021Johnson et al., 2021;Loeb and Winters, 2022;Perea et al., 2022) as well as winter hibernacula (Lacki et al., 2015;Powers et al., 2015;Perry and Jordan, 2020). ...
In the past decade, caverniculous bat populations have plummeted due to White-nose syndrome (WNS). Tri-colored bat ( Perimyotis subflavus ) populations have declined drastically in areas where WNS has been found, leading to the decision to protect tri-colored bats under the federal Endangered Species Act in the United States. At this time, there has not been a thorough review of the literature, nor a concise summary of the tri-colored bat’s life history, diet, threats, or habitat preferences. This absence creates more work for policy makers, federal “Take” permit applicants, and conservationists to find, access, and review critical details of tri-colored bats. A major point of confusion stems from the multiple common names and genera tri-colored bats have been classified under since it was first described a century and a half ago. To address the lack of concise summary, we scoured the scientific literature and compiled nearly a century of data to provide a robust review of the ecology, life history, winter and summer habitats, as well as created maps and figures showing counties where studies have occurred, white-nose syndrome is present, and where bats have been documented. Additionally, this paper highlights data gaps and suggests future research topics that may better inform conservation and management decisions for tri-colored bats.
... roosts may be buffered from both the spread of pathogens and mortality (Laughlin et al. 2019). In the East, the effects of WNS were lower on Myotis leibii (eastern small-footed bats), which tend to roost solitarily or in small aggregations during winter; populations did not decline significantly after the introduction of WNS Moosman et al. 2017;O'Keefe et al. 2019), and probability of presence actually increased in one study (Johnson et al. 2021). The absence of large hibernacula in caves and mines in the West also suggests the latter scenario. ...
... The difficulty of distinguishing M. lucifugus calls from those of Myotis volans (long-legged myotis) or Myotis ciliolabrum (western small-footed bat) in some areas further complicates efforts to monitor M. lucifugus in the West with acoustics. Long-term capture surveys at select sites provide important demographic information and have been used in many areas in the East to quantify changes in relative abundance of species over time, including in response to WNS(O'Keefe et al. 2019;Johnson et al. 2021;Reynolds et al. 2021). Capture surveys should be conducted wherever resources permit; however, implementing such a strategy extensively enough to generate statistically robust inferences across the West may be infeasible because of costs, training, travel logistics, and safety considerations. ...
White-nose syndrome (WNS) has notably affected the abundance of Myotis lucifugus (little brown myotis) in North America. Thus far, substantial mortality has been restricted to the eastern part of the continent where the cause of WNS, the invasive fungus Pseudogymnoascus destructans, has infected bats since 2006. To date, the state of Washington is the only area in the Western US (the Rocky Mountains and further west in North America) with confirmed cases of WNS in bats, and there the disease has spread more slowly than it did in the Eastern US. Here, we review differences between M. lucifugus in western and eastern parts of the continent that may affect transmission, spread, and severity of WNS in the West and highlight important gaps in knowledge. We explore the hypothesis that western M. lucifugus may respond differently to WNS on the basis of different hibernation strategies, habitat use, and greater genetic structure. To document the effect of WNS on M. lucifugus in the West most effectively, we recommend focusing on maternity roosts for strategic disease surveillance and monitoring abundance. We further recommend continuing the challenging work of identifying hibernation and swarming sites to better understand the microclimates, microbial communities, and role in disease transmission of these sites, as well as the ecology and hibernation physiology of bats in noncavernous hibernacula.
... Bats recovering from WNS often experience an energetically costly inflammatory response to heal the severe wing damage caused by the cutaneous fungal infection (Davy et al., 2017;Fuller et al., 2020;Meteyer et al., 2009Meteyer et al., , 2012. These pathophysiological consequences of WNS carry over to the summer maternity season and can further reduce the fitness of WNS survivors (Francl et al., 2012;Johnson et al., 2021). ...
Emerging infectious diseases in wildlife can threaten vulnerable host populations. Actions targeting habitat improvements to aid population resilience and recovery may be beneficial long‐term strategies, yet testing the efficacy of such strategies before major conservation investments are made can be challenging.
The disease white‐nose syndrome (WNS) has caused severe declines in several species of North American hibernating bats. We tested a novel conservation approach targeted at improving foraging conditions near bat hibernacula by experimentally manipulating insect density in the pre‐hibernation fattening period and spring emergence recovery period. We measured foraging (feeding buzzes) and echolocation activity of little brown bats Myotis lucifugus at ultraviolet (UV) light lures to determine behavioural response to augmented foraging conditions and characterized insect availability at UV light lures.
In the fall, bat foraging activity was three times greater (95% CI: 1.5–5.8; p = 0.002) when UV lights were on, but there was no statistical support for differences in echolocation activity response when our experimental design alternated between nights with lights on and off. In the spring, we allowed UV light lures to run consistently each night and compared with a control location in similar habitat. Bat foraging activity was 8.5 times greater (95% CI: 4.5–16.0; p < 0.0001) and echolocation activity was 4.4 times higher (95% CI: 3.0–6.5; p < 0.0001) at UV light lures in the spring experiment. In both the fall and spring, UV light lures resulted in concentrated insect availability, attracting primarily moths (Order: Lepidoptera). In both seasons, nightly temperature had a strong influence on bat foraging, echolocation and insect activity.
We show that a bat species threatened by WNS used enhanced foraging habitats near hibernacula during the critical pre‐ and post‐hibernation phases of their annual cycle. While light lures are unlikely to be a long‐term management strategy, our experiment provides initial evidence that bats behaviourally respond with increased foraging activity in areas with augmented insect prey availability. Our experimental results support developing management strategies focused on habitat protection, including restoration and enhancement of foraging habitats, in the immediate vicinity of bat hibernacula.
... As such, forest retention, restoration, and management have been core components of bat conservation in many regions of the world (Lacki et al., 2007). This includes eastern North America, where bats are additionally threatened by high mortality rates related to white-nose syndrome (O'Keefe et al., 2019;Johnson et al., 2021) and collision with wind turbines (Frick et al., 2017;Davy et al., 2021). However, many of the forests that have persisted in the face of land use change are managed for a wide variety of objectives. ...
Forests provide crucial foraging and roosting habitat to many bat species, and the gradual loss of forests is among the principal threats to global bat diversity. Forests that persist in the face of land use change are those that are managed for a variety of uses, including recreation, hunting, timber production, and wildlife conservation. Thus, understanding how bats respond to management is imperative to their conservation. We used radio telemetry to study the roosting and foraging behaviors of male and female eastern red bats (Lasiurus borealis). These forest-dependent bats roost in the foliage of live trees and are declining across their range. We tracked 26 bats (7 males and 18 females; one female was tracked twice) from May to August 2017-2019 in two state forests in south-central Indiana, USA. We estimated space use with 95% kernel density estimates and used generalized linear and linear mixed models to assess resource selection and use at three levels: population-level foraging selection, individual-level foraging use, and population-level roost selection. On average, eastern red bats foraged over a relatively small area (81 ha) and traveled a maximum distance of 1404 m from their roosts. The eastern red bat population foraged near maintained openings, recent regeneration openings, roads, and ponds within the study area. Within their foraging ranges, eastern red bats spent more time foraging near roads, ponds, and ridges. Eastern red bats roosted near maintained openings, recent regeneration openings, and ponds, switching roosts every two days. Roost trees were larger than random trees and were in plots containing fewer live stems than random plots. Together, these results reveal that some of the most important landscape features for eastern red bats are linear corridors (e.g., roads or ridgetops), forest openings (e.g., maintained openings and recent regeneration openings), perennial sources of water (e.g., ponds), and large trees. Overall, eastern red bats exhibited strong selection for managed portions of the forest, suggesting they can coexist with and likely benefit from timber management. When considering habitat for eastern red bats in central hardwood forests, we recommend land managers work to maintain large tracts of mature (>90 years old) forest, interspersed with young regeneration openings and provisioned with perennial water sources (e.g., ponds).
... P. destructans is known to affect nine species of North American bats, including several species in the genus Myotis (M. lucifugus, M. grisescens, M. septentrionalis, M. sodalis, M. leibii, M. austroriparius, and M. velifer), Eptesicus fuscus, and Perimyotis subflavus (Foley et al., 2011), devastating bat populations (Johnson et al., 2021;Thogmartin et al., 2012). ...
Emerging diseases in wildlife pose challenges for conservation due to their usually rapid spread and high cause of mortality. The transmission of these diseases is a complex ecological process that involves interactions between groups of individuals, particularly in gregarious species. White-nose syndrome, caused by the fungus Pseudogymnoascus destructans, is increasingly infecting species of vespertilionid North American bats causing, in some cases, high population mortality. In this study, we modeled ecological niches projected as potential distributions for three strains of P. destructans (Asian, European and North American) and a group of species of verpertilionid bats in North America. Our model showed that the ecological niches of North American and Asian fungi strains are projected to expand into new geographic areas, with statistical significance between the two strains. In addition, our model identified the presence of all three strains of fungi in areas where the fungus has previously been documented as well as new suitable climatic areas for the establishment of P. destructans in North America: large regions of the central USA and highlands of Mexico in the Peninsula of Baja California, the Sierra Madre Occidental and Oriental, and Transvolcanic Mexican Belt. Our models identified 10 species of vespertilionid bats distributed similarly to P. destructans. Bats had a high risk of infection with WSN and a strong likelihood of dispersing the fungus.
... During subsequent years, the disease spread from New York to adjacent U.S. states and is now found in 38 U.S. states and seven Canadian provinces (see https://www. whitenosesyndrome.org/ for a current map) and recent studies showed that several bat species in North America show a population level response with a significant decrease in presence and abundance post-WND [2][3][4]. The causative agent of WND has been identified as the psychrophilic fungus Pseudogymnoascus destructans Minnis & D.L. Lindner (= Geomyces destructans Blehert & Gargas) [1,5,6]. ...
Pseudogymnoascus destructans (= Geomyces destructans) is a psychrophilic filamentous fungus that causes White-Nose Disease (WND; the disease associated with White-Nose Syndrome, WNS) in hibernating bats. The disease has caused considerable reductions in bat populations in the USA and Canada since 2006. Identification and detection of the pathogen in pure cultures and environmental samples is routinely based on qPCR or PCR after DNA isolation and purification. Rapid and specific direct detection of the fungus in the field would strongly improve prompt surveillance, and support control measures. Based on the genes coding for ATP citrate lyase1 (acl1) and the 28S-18S ribosomal RNA intergenic spacer (IGS) in P. destructans, two independent LAMP assays were developed for the rapid and sensitive diagnosis of the fungus. Both assays could discriminate P. destructans from 159 tested species of filamentous fungi and yeasts. Sensitivity of the assays was 2.1 picogram per reaction (pg/rxn) and 21 femtogram per reaction (fg/rxn) for the acl1 and IGS based assays, respectively. Moreover, both assays also work with spores and mycelia of P. destructans that are directly added to the master mix without prior DNA extraction. For field-diagnostics, we developed and tested a field-applicable version of the IGS-based LAMP assay. Lastly, we also developed a protocol for preparation of fungal spores and mycelia from swabs and tape liftings of contaminated surfaces or infected bats. This protocol in combination with the highly sensitive IGS-based LAMP-assay enabled sensitive detection of P. destructans from various sources.
... However, long-term acoustic monitoring programs can be used to characterize how WNS-associated mortality and colony declines observed within hibernacula translate into activity declines outside the hiber nation period (e.g. Moosman et al. 2013, Pettit & O'Keefe 2017, Nocera et al. 2019, Hicks et al. 2020, Johnson et al. 2021. Acoustic monitoring is an efficient method for collecting data at large spatial scales and can be conducted in areas where bat capture is not possible (Duffy et al. 2000, Flaquer et al. 2007, Kunz et al. 2009). ...
White-nose syndrome (WNS) has emerged as the most serious threat to North American cave-dwelling bat species, with estimated mortality of over 6 million. Tri-colored bat Perimyotis subflavus is one of the species most affected, with hibernaculum counts at caves in WNS-positive regions reduced by >90% from previous counts. While declines have been documented in hibernaculum surveys, long-term monitoring programs during active seasons provide a unique opportunity to examine population trends and impact of population declines post-WNS. We developed generalized linear mixed models using data from a state-wide, long-term (2011–2020) mobile bat acoustic monitoring program in Georgia, USA, to better understand P. subflavus population trends before and after disease detection and between WNS-negative and WNS-positive regions. We recorded 5046 P. subflavus passes across all acoustic routes during the 10-year time period. We detected a significant decrease in activity 2 years after disease detection in the WNS-positive region, whereas activity in the WNS-negative region remained stable over time. Understanding changes in bat populations as WNS spreads and measuring the magnitude of population declines to assess disease impacts is crucial for providing appropriate guidance for management. Our results provide evidence of the critical status of P. subflavus in the southernmost WNS-positive region, but also emphasize the importance of monitoring WNS spread to new regions which could provide refugia for the species and a potential source of recolonization to WNS-affected areas.
The Tricolored Bat is an imperiled species due to white-nose syndrome. There is limited information available on roosting and foraging area use of the species to support planning and management efforts to benefit recovery in the Southeastern United States. Female tricolored bats exit hibernation and allocate energy toward disease recovery, migration, and reproduction. Providing and managing for summer habitat is 1 strategy to promote recovery. We sought to: (1) determine local- and landscape-scale factors that influence female Tricolored Bat roost selection; (2) quantify land cover use in core and overall foraging areas; and (3) define foraging area size and distances traveled by female tricolored bats in Tennessee. Bats in this study roosted in trees of variable sizes, in multiple tree species with large canopy volumes, and almost always roosted in trees with dead leaf foliage suspended in the canopy. Forest plots used by bats had trees averaging 30 cm diameter at breast height, basal areas averaging 27 m2/ha, contained multiple tree species, and comprised around a 50:50 ratio of canopy and subcanopy trees. Bats did not roost in coniferous forest areas and were only located in deciduous and mixed forest areas. Bats foraged near and directly over water, in open areas, and along forest edges. This study increases our knowledge on habitat requirements of the species in a temperate region dominated by unfragmented forests and many large water bodies and serves a baseline for management and efforts to benefit survival, reproduction, and population recovery.
