The eastern red bat (Lasiurus borealis) is widely considered to be in decline, inspiring interest in identifying important habitats for conservation in the eastern United States. Unfortunately, knowledge of important day-roosting habitats is lacking for much of the species' range. We examined patterns of day-roost selection by male and female eastern red bats at two study sites in southeastern Ohio, U. S. A, to help fill this information gap. We radiotagged 28 male and 25 female bats during the summers of 2016-2019 and located 53 male and 74 female roosts. Day-roost selection differed between sexes and study areas. In a mostly even-aged forest with significant historical disturbance, we found males and females roosting in trees located at higher elevations, with no clear selection based on tree or stand characteristics. Specifically, males selected trees with larger diameters located at lower, cooler elevations than females, which selected smaller diameter trees found at higher, warmer elevations. However, in a forest with less historical disturbance and more structural diversity, we found sexes differed in how they selected from available habitats. These data show that heterogeneity in environmental conditions can lead to different patterns in selection, even between sites located within a small geographic area. They also show that eastern red bats sexually segregate on the local landscape in the presence of diverse forest conditions but may not do so in the absence of such diversity. We recommend managing forests to maintain structural diversity across an elevational gradient to provide male and female eastern red bats with suitable day-roosting habitat in southeast Ohio.

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Temperate bat species cope with environmental temperatures outside their thermoneutral zone through physiological responses, habitat selection, and social roosting. While there have been several studies examining these factors in bat species that form maternity colonies in tree cavities, underneath bark, or in manmade structures, such studies rarely focus on bats that roost solitarily in tree foliage. To better understand the thermal environment of a foliage‐roosting bat and how they respond to thermal stimuli, we used temperature‐sensitive radio‐telemetry and environmental dataloggers to study the eastern red bat (Lasiurus borealis) in southeast Ohio. We collected skin temperatures from eight male and nine reproductive female bats in combination with microclimate data from 25 bat roosts and 15 random trees. We found that elevation, minimum ambient temperature, and maximum ambient temperature best predicted bat skin temperatures, while sex had little effect. We also found that trees located at higher elevations had warmer canopy microclimates than those at lower elevations, but temperatures did not differ between roost and random trees. These results show that solitary, foliage‐roosting species use torpor extensively in response to cool temperatures during summer. These results have conservation implications, indicating that areas on the landscape with warmer conditions are important for reducing the cost of maintaining euthermic body temperatures. In southeastern Ohio, this includes upland forests, but our data suggest that temperatures at slope positions, and not the elevation itself, are the important habitat feature for eastern red bats.