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In recent decades tree roosts of endangered Indiana bats (Myotis sodalis) have been more heavily studied than those of little brown bats (Myotis lucifugus), a much more common sympatric bat species. Motivated by precipitous declines in both species’ populations, we attempted to address this inconsistency by comparing the characteristics of these sibling species’ roosts. We used radio telemetry to find roosts of adult female bats of both species in two sites in southern Illinois and two sites in south-central Indiana. We then collected data on roost characteristics and bat movements. Little brown bats used more anthropogenic roosts and crevice/cavity roosts than Indiana bats, which used exfoliating bark roosts almost exclusively. Additionally, both species roosted in similar tree genera with similar DBHs (diameter at breast height) and roost heights. However, little brown bats roosted in shorter trees and in bigger clusters (based on emergence counts) than Indiana bats. Both species moved similar ...

Understanding population trends of any species is essential for conservation and management. However, due to difficulty in sampling some species, population status of many bat species is poorly understood. In an effort to resolve this issue, especially in light of emerging threats (e.g., white-nose syndrome and wind energy), a national mobile acoustic monitoring protocol, modeled after European programs, was developed to survey summer bat populations in the United States. While the program calls for conducting transects along roadways, some have suggested that waterways may allow for the gathering of more information. Therefore, we quantified species richness and abundance along car and boat transects to identify the most efficient mobile method. Furthermore, to compare the capabilities of mobile acoustic transects to a more traditional and better understood survey method, we compared species density along transects to stationary acoustic detectors. Using sample-based rarefaction, there was no difference ...

The partitioning of resources within communities is commonly associated with variation in morphological characteristics between species. However, communities containing morphologically similar species, such as the endangered Indiana bat (Myotis sodalis) and the little brown bat (M. lucifugus) must partition resources in different ways. We examined sympatric populations of M. sodalis and M. lucifugus to determine whether they partitioned their resources through the selection of foraging habitat. Foraging ranges, estimated using 100% minimum convex polygons (MCP) and 95% fixed kernel (FK) models, and foraging habitat selection, estimated using Euclidean distance-based habitat selection analyses, were examined and compared between the species using radiotelemetry. M. sodalis had a mean foraging range area of 375 6 39 ha and 285 6 32 ha (MCP and 95% FK, respectively), whereas M. lucifugus had a mean of 2,739 6 456 ha and 515 6 78 ha. Both species selected for similar hydric habitats at the landscape level. However, although M. lucifugus specifically selected for open water and bottomland hardwood forests within their expansive foraging ranges, M. sodalis used land cover types as they were available within their smaller home ranges, suggesting that these species use different foraging strategies, partitioning foraging resources through variation in their selection of land cover.

The only previous reported record of eastern small-footed bats (Myotis leibii) in Illinois was from a 2005 discovery of two individuals under a rock at the Fink Sandstone barrens of Shawnee National Forest (SNF). In Jun. 2011, the U.S. Fish and Wildlife Service requested information on the species to review potential listing under the Endangered Species Act. In response, managers at the SNF initiated a survey to determine if a resident population of eastern small-footed bats exists on the forest. We surveyed the SNF within Pope and Johnson Counties from 25 Jul.–16 Aug. 2011 by searching for day roosts under loose rocks on exposed rock outcrops. We discovered 29 individuals, including post lactating females and juveniles, along rock outcrops surrounding the 2005 site. While, the extent of M. leibii occurrence in Illinois is still poorly understood, our survey suggests that a resident breeding population occurs within the southern tip of the state.

Resource managers must consider climate change during their planning processes as future landscapes have the potential to vary greatly from current conditions. Military training and testing lands are extremely important and must be assessed for potential impacts of climate change. Climate change susceptibility analyses are commonly limited in their scope, thereby requiring multiple independent analyses within the same region. Without a standardized, comprehensive analysis method, the ability to prioritize areas susceptible to climate change within a region of interest is hindered. This deficit limits the applicability of results as well, further illustrating the need to develop a standardized method that incorporates multiple factors into a scalable framework to provide a more complete climate change susceptibility analysis. This framework must allow individual users the option of weighting environmental variables differently based on conservation concerns in managed areas. In this technical note, the authors present a method that allows multiple stakeholders each with their own management requirements and concerns for assessing susceptibility to use a common framework to assess climate change susceptibility. This framework enables improved analytical results of climate change to be incorporated into long-term regional conservation planning. The framework should prove to be a valuable tool for resource managers faced with integrating the potential impacts of climate change into their natural resource plans.