Landscape-scale distribution of tree roosts of the northern long-eared bat in Mammoth Cave National Park, USA

Abstract

Context The roosting habits of many temperate zone bats are well documented at microhabitat scales, but fewer studies have included multi-scale assessments of landscape patterns in bat roost site selection. Objectives To identify and assess at the landscapescale the location of spring and early season maternity roosts of female northern long-eared bats (Myotis septentrionalis) from 2015 to 2016 at Mammoth Cave National Park (MACA), Kentucky, USA. Methods We used mist-nets and radiotelemetry to catch and track bats to roost trees across the landscape of MACA. Data on roosting sites were evaluated using spatial point pattern analysis to examine distributional trends of roosts. A variety of spatial covariates were used to model the effect of landscape pattern, including: forest type, elevation, and proximity to hibernacula, water, and road corridors. Results Data indicate that roost locations of female northern long-eared bats in MACA were typically situated within 2000 m of known winter hibernacula, occurring more often at higher elevations in mesic upland deciduous forests, and in close proximity to water sources and roads. We present hypotheses to account for the patterns observed in relation to landscape features and habitat resources in the Park. Conclusions Our data indicate that a more comprehensive understanding of habitat requirements which includes empirically-based, landscape-scale patterns, and not solely considerations at stand or local levels, could lead to better informed management policies targeting conservation of maternity habitat of forestdwelling bats, including the northern long-eared bat, a species in decline throughout much of its distribution in North America. Keywords Bats Á Landscape patterns Á Maternity season Á Myotis septentrionalis Á Roosting habitat Á Spatial point pattern Á Spring staging Á Winter hibernacula

Systematic Review of the Roost-Site Characteristics of North American Forest Bats: Implications for Conservation

“…While males and nonreproductive females may be less restricted by their biological needs, pregnant and lactating females tend to select roosts with closer proximity to foraging resources [140]. Landscape attributes have significant predictive power when evaluating roost-site suitability [177], and including more data regarding the landscape in which roosts are situated may have provided additional context for the results of our study. However, we did not have enough datasets containing these measurements to explore the topic further.…”

“…Easy access to these metrics make them readily available data sources. Preferable roost trees tend to be near water [106,176] and/or corridors [86,177], thus reducing the energetic demands of foraging. While males and nonreproductive females may be less restricted by their biological needs, pregnant and lactating females tend to select roosts with closer proximity to foraging resources [140].…”