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Given the likelihood of regional extirpation of several once-common bat species in eastern North America from white-nose syndrome, it is critical that the impacts of forest management activities, such as prescribed fire, are known in order to minimize potentially additive negative effects on bat populations. Historic wildfires may offer a suitable surrogate to assess long-term burn impacts on bats for planning, implementing and assessing burn programs. To examine the effects of historic fire on bats, we sampled bat activities at 24 transect locations in burned and unburned forest stands in the central Appalachian Mountains of Shenandoah National Park (SNP), Virginia, USA. There was limited evidence of positive fire effects over time on hoary bats (Lasiurus cinereus Beauvois) and big brown bats (Eptesicus fuscus Beauvois) occupancy. Overall, there were few or mostly equivocal relationships of bat occupancy relative to burn conditions or time since fire in SNP across species using a false-positive occupancy approach. Our results suggest that fire does not strongly affect bat site occupancy short- or long-term in the central Appalachians.

Many central Appalachian ridges offer high wind potential, making them attractive to future wind-energy development. Understanding seasonal and hourly activity patterns of migratory bat species may help to reduce fatalities at wind-energy facilities and provide guidance for the development of best management practices for bats. To examine hourly migratory bat activity patterns in the fall and spring in Virginia in an exploratory fashion with a suite of general temporal, environmental, and weather variables, we acoustically monitored bat activity on five ridgelines and side slopes from early September through mid-November 2015 and 2016 and from early March through late April 2016 and 2017. On ridges, bat activity decreased through the autumn sample period, but was more variable through the spring sample period. In autumn, migratory bat activity had largely ceased by mid-November. Activity patterns were species specific in both autumn and spring sample periods. Generally, migratory bat activity was negatively associated with hourly wind speeds but positively associated with ambient temperatures. These data provide further evidence that operational mitigation strategies at wind-energy facilities could help protect migratory bat species in the Appalachians; substantially slowing or locking wind turbine blade spin during periods of low wind speeds, often below where electricity is generated, and warm ambient temperatures may minimize mortality during periods of high bat activity. Joint Fire Science Program through the U.S. Geological Survey Cooperative Research Unit Program [G14AC00316]; U.S. Geological Survey Disease Program through the U.S. Geological Survey Cooperative Research Unit Program [G15AC00487] Funding was provided by the Joint Fire Science Program Grant #G14AC00316 and U.S. Geological Survey Disease Program Grant #G15AC00487 through the U.S. Geological Survey Cooperative Research Unit Program. We thank the U.S. Forest Service and the National Park Service for allowing site access for this research. Acoustic monitoring equipment was provided by Bat Conservation International. S. Sweeten and L. Austin performed invaluable field assistance. This manuscript was greatly improved by the thoughtful comments of the Associate Editor and three anonymous reviewers. Public domain – authored by a U.S. government employee

We report the first confirmed Myotis sodalis (Indiana Bat) maternity colony in Virginia, discovered at Fort A.P. Hill Military Reservation in Caroline County along the Piedmont-Coastal Plain Fall Line. Acoustic surveys conducted in 2014 indicated likely presence of Indiana Bats on the installation. Subsequent focal mist-netting during May–June 2015 resulted in capture of 4 lactating females that we subsequently radio tracked to a maternity colony site containing at least 20 individuals. The core roosting-area was comprised of Pinus taeda (Loblolly Pine) snags with abundant exfoliating bark and high solar exposure. This forest patch was adjacent to a large emergentshrub wetland and within a larger matrix of mature, mid-Atlantic hardwood forests. The site where we found the colony location is 140 km east of the nearest known hibernaculum and is outside of the previously documented extent of this species' occurrence.

With the declines in abundance and changing distribution of white-nose syndrome-affected bat species, increased reliance on acoustic monitoring is now the new "normal." As such, the ability to accurately identify individual bat species with acoustic identification programs has become increasingly important. We assessed rates of disagreement between the three U.S. Fish and Wildlife Service-approved acoustic identification software programs (Kaleidoscope Pro 4.2.0, Echoclass 3.1, and Bat Call Identification 2.7d) and manual visual identification using acoustic data collected during summers from 2003 to 2017 at Fort Drum, New York. We assessed the percentage of agreement between programs through pairwise comparisons on a total nightly count level, individual file level (e.g., individual echolocation pass call file), and grouped maximum likelihood estimate level (e.g., probability values that a species is misclassified as present when in fact it is absent) using preplanned contrasts, Akaike Information Criterion, and annual confusion matrices. Interprogram agreement on an individual file level was low, as measured by Cohen's Kappa (0.2-0.6). However, site-night level pairwise comparative analysis indicated that program agreement was higher (40-90%) using single season occupancy metrics. In comparing analytical outcomes of our different datasets (i.e., how comparable programs and visual identification are regarding the relationship between environmental conditions and bat activity), we determined high levels of congruency in the relative rankings of the model as well as the relative level of support for each individual model. This indicated that among individual software packages, when analyzing bat calls, there was consistent ecological inference beyond the file-by-file level at the scales used by managers. Depending on objectives, we believe our results can help users choose automated software and maximum likelihood estimate thresholds more appropriate for their needs and allow for better cross-comparison of studies using different automated acoustic software. Fort Drum Military Installation through U.S Army Corps of Engineers [W9126G-15-2-0005] The Fort Drum Military Installation through U.S Army Corps of Engineers contract W9126G-15-2-0005 via the Southern Appalachia Cooperative Ecosystems Study Unit Program supported this work. We thank J. Rodrigue and C. Whitman for field assistance. Earlier drafts of this article were reviewed by B. Carstensen. The comments of the Associate Editor and three anonymous reviewers substantially improved this article. Public domain – authored by a U.S. government employee

Previous acoustic surveys, netting, and count data have shown that overall bat activity patterns have shifted among most species between pre- and post-white-nose syndrome (WNS) years in much of North America where WNS has occurred. However, the significance of these changes is based on the species-specific susceptibility to WNS. We used acoustically recorded echolocation passes obtained at Fort Drum, New York to describe changes in bat activity pre-WNS (2004-2007) to post-WNS (2008-2018). We examined seasonal and yearly changes in bat activity as they relate to the presence of WNS at hibernacula near (

Fission–fusion dynamics appear common among temperate bats where females form roost groups that change in size and composition, as females switch roosts almost daily. One hypothesis for frequent roost switching is that females move to find suitable thermal conditions as ambient conditions change. Tests of this hypothesis have, however, been conducted mostly at roosts in artificial structures where microclimate is relatively stable. The goal of our study was to determine whether roost switching and roost use by northern long-eared bats, Myotis septentrionalis, that roost in trees are related to ambient conditions. We used generalized linear fixed effects models to explore the influence of roost characteristics and changes in ambient conditions on the likelihood of roost switching. We used canonical correlation analyses to examine the relationship between ambient conditions and roost characteristics. Roost switching was indeed linked to ambient conditions together with characteristics of roosts on the previous day; the best descriptors of roost switching differed between the two geographical regions we analysed. In Nova Scotia, females were less likely to switch roosts when it rained, particularly if they were in roosts below surrounding canopy whereas they were more likely to switch roosts when they were in roosts of high decay. Females roosted in shorter trees in earlier decay classes on warm days, as well as on windy and rainy days. In Kentucky, females were more likely to switch roosts at high temperatures, particularly when they were in roosts in high decay. Females roosted in shorter, decayed trees on warm days, and in less decayed trees with small diameter on windy and rainy days. Our results suggest bats switch roosts in response to changes in ambient conditions to select suitable roosting conditions, which may explain some of the proximate factors shaping fission–fusion dynamics of bats.

Changes to hat distribution and habitat associations at the local to sub-landscape scale in the post white-nose syndrome (WNS) environment have received little attention to date despite being critical information for managers. To better understand the spatial nature of hat population declines, we modelled both activity patterns and occupancy from acoustic surveys for the Myotis lucifugus (little brown hat) on Fort Drum Military Installation in New York, USA over 15 summers (2003-2017) that span the pre-WNS, WNS-advent (2008) and post-WNS periods, using a set of generalized linear mixed models and geospatial analysis. Our best supported model indicated significant differences between years with significant declines in activity post-WNS. M. lucifugus activity was most closely associated with woody wetland habitats over the study period, however, the spatial patterns of high activity areas were variable over years, with the areal extent of these high activity areas decreasing post-WNS. Our best supported occupancy model varied by year. However, the null occupancy model [Psi(.)] was either competing (within 2 Delta AIC units) or was the best supported model. Meaning that none of our environmental variables seemed to impact occupancy, and when they did, these differences were not significant. There was high disagreement between our relative activity models and predictions compared to our occupancy models, suggesting that geographic spatial scale and the resolution of the data impacts model outcome. Our results indicate that continued acoustic monitoring of hat species in the Northeast to assess ongoing temporal and spatial changes in habitat associations and to provide direction for future mist-netting studies should rely more on relative activity as the metric of choice rather than site occupancy. U.S Army Corps of EngineersUnited States Department of Defense [W9126G-15-2-0005]; Southern Appalachian Cooperative Ecosystems Study Unit Program This work was supported by the U.S Army Corps of Engineers [W9126G-15-2-0005] through the Southern Appalachian Cooperative Ecosystems Study Unit Program. We thank C. Whitman for field assistance. Earlier drafts of this manuscript were reviewed by B. Carstensen. and K. Powers. The use of any trade, product or firm names does not imply endorsement by the U.S. government. Public domain – authored by a U.S. government employee

Background To restore and manage fire-adapted forest communities in the central Appalachians, USA, land managers are now increasingly prioritizing use of prescribed fire. However, it is unclear how the reintroduction of fire following decades of suppression will affect bat communities, particularly where white-nose syndrome-related population declines of many cave-hibernating bat species have occurred. To address this concern, we monitored and compared bat activity in burned and unburned habitat across a temporal gradient in western Virginia. Results We found evidence for slightly positive fire effects on activity levels of the northern long-eared bat (Myotis septentrionalis [Trouessart, 1897]), Indiana bat (Myotis sodalis [Miller and Allen, 1928]), little brown bat (Myotis lucifugus [Le Conte, 1831]), big brown bat (Eptesicus fuscus [Palisot de Beauvois, 1796])/silver-haired bat (Lasionycteris noctivagans [Le Conte, 1831]) group, all high-frequency bats, and all bat species combined. We observed temporal effects only for the big brown bat, with a negative relationship between activity and time since fire. Conclusions Because response of bat activity was neutral to weakly positive relative to burned forest condition, our results suggest that bats are not a resource that would impede the use of this management tool in the central Appalachians. Published version

After decades of fire suppression in eastern North America, land managers now are prioritizing prescribed fire as a management tool to restore or maintain fire-adapted vegetation communities. However, in long-fire-suppressed landscapes, such as the central and southern Appalachians, it is unknown how bats will respond to prescribed fire in both riparian and upland forest habitats. To address these concerns, we conducted zero-crossing acoustic surveys of bat activity in burned, unburned, riparian, and non-riparian areas in the central Appalachians, Virginia, USA. Burn and riparian variables had model support (Delta AICc < 4) to explain activity of all bat species. Nonetheless, parameter estimates for these conditions were small and confidence intervals overlapped zero for all species, indicating effect sizes were marginal. Our results suggest that bats respond to fire differently between upland and riparian forest habitats, but overall, large landscape-level prescribed fire has a slightly positive to neutral impact on all bats species identified at our study site post-fire application. Joint Fire Science Program Grant through the US Geological Survey Cooperative Research Unit Program [G14AC00316]; National Park Service White-nose Syndrome Program Grant through the Southern Appalachian Cooperative Ecosystem Studies Unit at Virginia Tech [P14AC01042] Funding was provided by the Joint Fire Science Program Grant #G14AC00316 through the US Geological Survey Cooperative Research Unit Program and National Park Service White-nose Syndrome Program Grant #P14AC01042 through the Southern Appalachian Cooperative Ecosystem Studies Unit at Virginia Tech. Amanda Rhyne and Katie Patrum provided indispensable field assistance. We thank Steve and Carol Croy of the US Forest Service and Marek Smith and Laurel Schablein of The Nature Conservancy for burn history data and logistical support. The use of any trade, product, or firm names does not imply endorsement by the US government. Public domain – authored by a U.S. government employee

Little is known about the effects that oak forest regeneration treatments consisting of a combination of shelterwood harvesting and prescribed fire have on bats, despite increasing use of these treatments. We quantified changes in bat activity levels in relation to oak forest regeneration treatments consisting of harvesting at 50% and 70% retention levels and prescribed fire in two upland Appalachian hardwood forests in Ohio. We monitored bat activity immediately post-harvest, three growing seasons post-harvest, and after application of prescribed fire to harvested stands before the fourth growing season. Total bat activity levels were higher in thinned and thinned and burned treatments than in unthinned controls in all years, but did not differ between harvest treatment levels immediately post-harvest, three growing seasons post-harvest, or between harvest treatment levels within years. Total bat activity post-prescribed fire changed only in the 50% retention harvest treatment blocks, wherein activity decreased. Activity levels of big brown (Eptesicus fuscus) bats were greater in harvested treatment blocks than controls in all years. Activity levels of eastern red (Lasiurus borealis), and Myotis spp. and tri-colored (Perimyotis subflavus) collectively did not differ among treatment blocks post-fire, but were greater in harvested treatment blocks than controls three growing seasons post-harvest. Community composition was strongly related to vegetation volume, with eastern red bats and Myotis and tri-colored bats displaying positive relationships with clutter in low height strata, and big brown bats displaying a negative relationship with clutter in all height strata. The positive relationship between eastern red and Myotis and tri-colored bats and clutter in low height strata may explain why activity levels of these species decreased post-prescribed fire. Our study suggests that the harvesting component of oak forest regeneration treatments may benefit bats for several years, and that while bat activity levels may decline post-prescribed fire, overall activity levels are nonetheless greater than in unthinned areas.

The northern long-eared bat (Myotis septentrionalis Trovessart) is a cavity- roosting species that forages in cluttered upland and riparian forests throughout the oak-dominated Appalachian and Central Hardwoods regions. Common prior to white-nose syndrome, the population of this bat species has declined to functional extirpation in some regions in the Northeast and Mid-Atlantic, including portions of the central Appalachians. Our long-term research in the central Appalachians has shown that maternity colonies of this species form non-random assorting networks in patches of suitable trees that result from longand short-term forest disturbance processes, and that roost loss can occur with these disturbances. Following two consecutive prescribed burns on the Fernow Experimental Forest in the central Appalachians, West Virginia, USA, in 2007 to 2008, post-fire counts of suitable black locust (Robinia pseudoacacia L.; the most selected species for roosting) slightly decreased by 2012. Conversely, post-fire numbers of suitable maple (Acer spp. L.), primarily red maple (Acer rubrum L.), increased by a factor of three, thereby ameliorating black locust reduction. Maternity colony network metrics such as roost degree (use) and network density for two networks in the burned compartment were similar to the single network observed in unburned forest. However, roost clustering and degree of roost centralization was greater for the networks in the burned forest area. Accordingly, the short-term effects of prescribed fire are slightly or moderately positive in impact to day-roost habitat for the northern long-eared bat in the central Appalachians from a social dynamic perspective. Listing of northern long-eared bats as federally threatened will bring increased scrutiny of immediate fire impacts from direct take as well as indirect impacts from long-term changes to roosting and foraging habitat in stands being returned to historic fire-return conditions. Unfortunately, definitive impacts will remain speculative owing to the species' current rarity and the paucity of forest stand data that considers tree condition or that adequately tracks snags spatially and temporally. US Forest Service Northern Research StationUnited States Department of Agriculture (USDA)United States Forest Service; US Geological Survey, Cooperative Research Unit program

The listing of the northern long-eared bat (Myotis septentrionalis) as federally threatened under the Endangered Species Act following severe population declines from white-nose syndrome presents considerable challenges to natural resource managers. Because the northern long-eared bat is a forest habitat generalist, development of effective conservation measures will depend on appropriate understanding of its habitat relationships at individual locations. However, severely reduced population sizes make gathering data for such models difficult. As a result, historical data may be essential in development of habitat models. To date, there has been little evaluation of how effective historical bat presence data, such as data derived from mist-net captures, acoustic detection, and day-roost locations, may be in developing habitat models, nor is it clear how models created using different data sources may differ. We explored this issue by creating presence probability models for the northern long-eared bat on the Fernow Experimental Forest in the central Appalachian Mountains of West Virginia using a historical, presence-only data set. Each presence data type produced outputs that were dissimilar but that still corresponded with known traits of the northern long-eared bat or are easily explained in the context of the particular data collection protocol. However, our results also highlight potential limitations of individual data types. For example, models from mist-net capture data only showed high probability of presence along the dendritic network of riparian areas, an obvious artifact of sampling methodology. Development of ecological niche and presence models for northern long-eared bat populations could be highly valuable for resource managers going forward with this species. We caution, however, that efforts to create such models should consider the substantial limitations of models derived from historical data, and address model assumptions. U.S. Forest Service Northern Research StationUnited States Department of Agriculture (USDA)United States Forest Service; U.S. Geological SurveyUnited States Geological Survey; Cooperative Research Unit Program; Virginia Tech Department of Fish and Wildlife Conservation U.S. Forest Service Northern Research Station, U.S. Geological Survey, Cooperative Research Unit Program, and Virginia Tech Department of Fish and Wildlife Conservation provided financial support for this project. Field assistance was provided by D. Lowther and R. Hovatter. We thank C. Johnson for numerous discussions about northern long-eared bat ecology that ultimately led to this research endeavor. We thank the three anonymous reviewers for their helpful comments. Public domain – authored by a U.S. government employee

Though characterization of, and understanding determinants of, social structure in bats is increasing, little is known about how bat social groups respond to disturbance resulting in roost loss. Given that many species of bats roost in ephemeral or transitory resources such as plants, it is clear that bat social groups can tolerate some level of roost loss. Understanding responses of bat social groups to roost loss can provide insight into social structure that have applied conservation use. Herein, we review the existing literature on the effects of disturbance on bat social groups, and present a parameterizable agent-based model that can be used to explore the relationships among roost dynamics, population dynamics, and social behavior.

Forest roosting bats use a variety of ephemeral roosts such as snags and declining live trees. Although conservation of summer maternity habitat is considered critical for forest-roosting bats, bat response to roost loss still is poorly understood. To address this, we monitored 3 northern long-eared bat (Myotis septentrionalis) maternity colonies on Fort Knox Military Reservation, Kentucky, USA, before and after targeted roost removal during the dormant season when bats were hibernating in caves. We used 2 treatments: removal of a single highly used (primary) roost and removal of 24% of less used (secondary) roosts, and an un-manipulated control. Neither treatment altered the number of roosts used by individual bats, but secondary roost removal doubled the distances moved between sequentially used roosts. However, overall space use by and location of colonies was similar pre- and post-treatment. Patterns of roost use before and after removal treatments also were similar but bats maintained closer social connections after our treatments. Roost height, diameter at breast height, percent canopy openness, and roost species composition were similar pre- and post-treatment. We detected differences in the distribution of roosts among decay stages and crown classes pre- and post-roost removal, but this may have been a result of temperature differences between treatment years. Our results suggest that loss of a primary roost or ≤ 20% of secondary roosts in the dormant season may not cause northern long-eared bats to abandon roosting areas or substantially alter some roosting behaviors in the following active season when tree-roosts are used. Critically, tolerance limits to roost loss may be dependent upon local forest conditions, and continued research on this topic will be necessary for conservation of the northern long-eared bat across its range. Data: http://hdl.handle.net/10919/50954 Published version

This report discusses characteristics of seven tree cavities used as day-roosts by female northern long-eared bats (Myotis septentrionalis) during the maternity season in a deciduous forest in north-central Kentucky. Understanding the characteristics of cavities selected by bats will help us better understand the ecology of cavity roosting bats and the tree species and condition necessary for providing day-roost habitat. Cavity openings were created by either fungal decay or primary excavators. Length and volume of cavities were positively related to number of entrances. Mean area of entrances was positively related to the proportion of entrances created by primary excavators.

Social dynamics are an important but poorly understood aspect of bat ecology. Herein we use a combination of graph theoretic and spatial approaches to describe the roost and social network characteristics and foraging associations of an Indiana bat (Myotis sodalis) maternity colony in an agricultural landscape in Ohio, USA. We tracked 46 bats to 50 roosts (423 total relocations) and collected 2,306 foraging locations for 40 bats during the summers of 2009 and 2010. We found the colony roosting network was highly centralized in both years and that roost and social networks differed significantly from random networks. Roost and social network structure also differed substantially between years. Social network structure appeared to be unrelated to segregation of roosts between age classes. For bats whose individual foraging ranges were calculated, many shared foraging space with at least one other bat. Compared across all possible bat dyads, 47% and 43% of the dyads showed more than expected overlap of foraging areas in 2009 and 2010 respectively. Colony roosting area differed between years, but the roosting area centroid shifted only 332 m. In contrast, whole colony foraging area use was similar between years. Random roost removal simulations suggest that Indiana bat colonies may be robust to loss of a limited number of roosts but may respond differently from year to year. Our study emphasizes the utility of graphic theoretic and spatial approaches for examining the sociality and roosting behavior of bats. Detailed knowledge of the relationships between social and spatial aspects of bat ecology could greatly increase conservation effectiveness by allowing more structured approaches to roost and habitat retention for tree-roosting, socially-aggregating bat species. Published version

Fuels reduction decisions are made within a larger context of resource management characterized by multiple objectives including ecosystem restoration, wildlife management, commodity production (from timber to nontraditional forest products), and provision of recreation opportunities and amenity values. Implementation of fuels treatments is strongly influenced by their perceived influence on and compatibility with overarching management objectives. In some cases these objectives may be complementary while in others they may involve difficult tradeoffs. Such tradeoffs are only further complicated by institutional mandates, limited availability of information, and complex ownership patterns. Like natural resource managers across the United States, those in the northern Lake States must balance these competing demands as they seek to build their management programs. However, there is limited information available to support these management decisions in the mixed red (Pinus resinosa Ait.) and eastern white pine (P. strobus L.) forests of the northern Lake States. This report informs fuels management decisions in the northern Lake States by synthesizing existing knowledge from the fields of silviculture, forest ecology, wildlife ecology, forest economics, public acceptance, and decision science. We provide an overview of forests and fire regimes in the northern Lake States followed by a description of different fuels treatment techniques and their expected outcomes. We then include a discussion of comprehensive management principles to consider in developing fire and fuels management programs for the region.

How wildlife social and resource networks are distributed on the landscape and how animals respond to resource loss are important aspects of behavioral ecology. For bats, understanding these responses may improve conservation efforts and provide insights into adaptations to environmental conditions. We tracked maternity colonies of northern bats (Myotis septentrionalis) at Fort Knox, Kentucky, USA to evaluate their social and resource networks and space use. Roost and social network structure differed between maternity colonies. Overall roost availability did not appear to be strongly related to network characteristics or space use. In simulations for our two largest networks, roost removal was related linearly to network fragmentation; despite this, networks were relatively robust, requiring removal of >20% of roosts to cause network fragmentation. Results from our analyses indicate that northern bat behavior and space use may differ among colonies and potentially across the maternity season. Simulation results suggest that colony social structure is robust to fragmentation caused by random loss of small numbers of roosts. Flexible social dynamics and tolerance of roost loss may be adaptive strategies for coping with ephemeral conditions in dynamic forest habitats.

Context Understanding habitat selection is important for determining conservation and management strategies for endangered species. The Carolina northern flying squirrel (CNFS; Glaucomys sabrinus coloratus) is an endangered subspecies found in the high-elevation montane forests of the southern Appalachians, USA. The primary use of nest boxes to monitor CNFS has provided biased information on habitat use for this subspecies, as nest boxes are typically placed in suitable denning habitat. Aims We conducted a radio-telemetry study on CNFS to determine home range, den site selection and habitat use at multiple spatial scales. Methods We radio-collared 21 CNFS in 2012 and 2014–15. We tracked squirrels to diurnal den sites and during night-time activity. Key results The MCP (minimum convex polygon) home range at 95% for males was 5.2±1.2ha and for females was 4.0±0.7. The BRB (biased random bridge) home range at 95% for males was 10.8±3.8ha and for females was 8.3±2.1. Den site (n=81) selection occurred more frequently in montane conifer dominate forests (81.4%) vs northern hardwood forests or conifer–northern hardwood forests (9.9% and 8.7%, respectively). We assessed habitat selection using Euclidean distance-based analysis at the 2nd order and 3rd order scale. We found that squirrels were non-randomly selecting for habitat at both 2nd and 3rd order scales. Conclusions At both spatial scales, CNFS preferentially selected for montane conifer forests more than expected based on availability on the landscape. Squirrels selected neither for nor against northern hardwood forests, regardless of availability on the landscape. Additionally, CNFS denned in montane conifer forests more than other habitat types. Implications Our results highlight the importance of montane conifer to CNFS in the southern Appalachians. Management and restoration activities that increase the quality, connectivity and extent of this naturally rare forest type may be important for long-term conservation of this subspecies, especially with the impending threat of anthropogenic climate change.

Conservation of summer maternity roosts is considered critical for bat management in North America, yet many aspects of the physical and environmental factors that drive roost selection are poorly understood. We tracked 58 female northern bats (Myotis septentrionalis) to 105 roost trees of 21 species on the Fort Knox military reservation in north-central Kentucky during the summer of 2011. Sassafras (Sassafras albidum) was used as a day roost more than expected based on forest stand-level availability and accounted for 48.6% of all observed day roosts. Using logistic regression and an information theoretic approach, we were unable to reliably differentiate between sassafras and other roost species or between day roosts used during different maternity periods using models representative of individual tree metrics, site metrics, topographic location, or combinations of these factors. For northern bats, we suggest that day-roost selection is not a function of differences between individual tree speciesper se, but rather of forest successional patterns, stand and tree structure. Present successional trajectories may not provide this particular selected structure again without management intervention, thereby suggesting that resource managers take a relatively long retrospective view to manage current and future forest conditions for bats.