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There is an intense interest in the effects of timber harvest on forest-dwelling bats due to the potential for timber harvest to reduce available habitat. Knowledge of these effects would be especially significant for the conservation of threatened and endangered bat species, many of which are forest obligates. We conducted a study to determine how endangered Indiana bats ( Myotis sodalis ) select summer roosts within a managed midwestern forest. In the summers of 2012–2015, we tracked 4 male and 11 female Indiana bats to 49 roosts (n male  = 24, n female  = 25) in south-central Indiana, USA. We collected roost-, plot-, and stand-scale data on roosts and associated available trees, randomly located throughout the same landscape. We generated 10 matched pairs conditional logistic regression models based on a priori hypotheses on roost selection and ranked them using Akaike’s Information Criteria. Plausible models explaining female roost selection included those describing typical Indiana bat maternity roosts (tall and solar-exposed roosts) and typical tree-cavity bat roosts (tall, solar-exposed roosts close to water and surrounded by snags). Females selected roosts under exfoliating bark on large (averaging 17 ± 2 m in height and 34.8 ± 3.0 cm in diameter) standing dead trees (snags; 72% of roosts) and in bat boxes (20% of roosts) with high solar exposure (28.0 ± 6.0% canopy closure above roosts). For males, the model describing predator avoidance (tall roosts with many available snags and live trees) was the most plausible explanation of roost selection. Males selected for roosts under exfoliating bark on tall trees (23 ± 2 m; 71% snags, 25% live trees) surrounded by snags (4.5 ± 0.7 snags/0.1 ha plot) and live trees (30.4 ± 2.7 live trees/0.1 ha plot). Roost selection models including distance to timber harvest openings were not plausible. However, females roosted in or ≤10 m from harvest openings and first-stage shelterwood cuts more than expected (15 of 25 roosts) based on their availability on the landscape. Males roosted in harvest openings as expected (3 of 24 roosts). Our results demonstrate that a managed midwestern forest provides an array of roosts for Indiana bats and that Indiana bats do not actively avoid roosting near harvest openings in this forest. This suggests that Indiana bats may be able to subsist in managed forests in south-central Indiana, provided adequate maternity roost habitat (i.e., large standing dead trees with high solar exposures) is available. [ABSTRACT FROM AUTHOR]

ABSTRACT Threats to North American bat species necessitate the quantification of bat habitat. To characterize bat habitat, we recorded bat echolocation calls from state forests in Indiana, USA. We identified calls using automated classification software and constructed detection histories for 3 species of conservation concern: Indiana bat ( Myotis sodalis), little brown bat ( Myotis lucifugus), and northern long-eared bat ( Myotis septentrionalis). We analyzed these data using single- and multi-species occupancy approaches to estimate occurrence and detection probabilities at the genus level ( Myotis) and for each species separately. We constructed models using a suite of habitat covariates (e.g., forest cover, edge, streams, hibernacula, public roads) and determined the effect of these features on occupancy for each species (or group). We validated all models using training and independent data. Occupancy of all species was affected by the proportion of forest in surrounding areas. For most models, bat occupancy was greatest in areas with a lower proportion of forest within 1 km. Occupancy was also often greatest in recently harvested or intact, mature second-growth stands as opposed to stands 10-30 years following harvest. The spatial configuration of water and roads also affected species occupancy. Our methods allowed us to assess the factors that affect occupancy for the genus and individual species, thus allowing for the identification of features useful in classifying important habitat at both taxonomic levels. The results of this study can aid land managers in identifying habitat that may be used by foraging bats and in planning future timber harvests in managed forests. © 2017 The Wildlife Society. [ABSTRACT FROM AUTHOR]

• Foraging habitat is as essential as roosts for maternity colonies. • Myotis sodalis forages over twice the spatial area than M. septentrionalis. • Both species took advantage of small regeneration openings and ponds. • Within species, individuals exhibit differing habitat preferences. • Maintaining heterogeneous forests supports multiple bat species. Bat populations face numerous threats, including the loss of forests in which they roost and forage. Present-day forests are commonly managed for timber harvesting, recreation, and wildlife. Understanding bat responses to forest management is crucial for balancing the conservation of endangered bats and forest restoration. We used radio telemetry to study nocturnal movements and habitat selection patterns of female and juvenile bats of two forest-dependent, federally listed bat species in an oak-dominated managed forest. We estimated foraging space use and assessed habitat selection for 33 northern long-eared bats (Myotis septentrionalis) and 25 Indiana bats (Myotis sodalis) from May to August 2014–2017 in south-central Indiana, USA. Myotis septentrionalis space use averaged 176 ha and bats selected water, historic thinning, and patch cuts (≤4 ha) over other habitats, with all but one bat avoiding larger openings (≥4-ha clearcuts). Myotis sodalis space use averaged 343 ha and bats selected 4-ha patch cuts, historic openings, and historic thinning over other habitats. In contrast to M. septentrionalis , one-third of the M. sodalis foraged over larger clearcuts, while two-thirds foraged over smaller openings and thinnings. We showed that bats were attracted to small regeneration harvests of varying structural ages. Forests maintained for a mix of mature stands, thinned stands, shelterwoods, small regenerative cuts (<7 ha), and small water sources should provide suitable foraging habitat for these endangered Myotis species, while also promoting forest regeneration. [ABSTRACT FROM AUTHOR]