Selection of roosting habitat by male Myotis bats in a boreal forest

Abstract

Male little brown bats (Myotis lucifugus (Le Conte, 1831)) and northern long-eared bats (Myotis septentrionalis (Trouessart, 1897)) often roost under exfoliating bark, within trunks, and within cavities of trees during summer. Current lack of knowledge about the roosting ecology of these species in boreal forest limits our understanding of how they may be affected by logging. The main objective was to identify tree and forest stand features that were selected by bats for roosting within a balsam fir (Abies balsamea (L.) Mill.) – paper birch (Betula papyrifera Marshall) forest of Quebec, Canada. Over 3 years, we captured and fitted radio transmitters to 22 individual bats to locate their roost trees for 7–14 days following release. We measured tree and forest stand features in the field and using light detection and ranging (LiDAR) technology. Roost trees were compared with random trees using generalized linear mixed models. Male Myotis bats selected larger and taller snags, within stands containing a higher proportion of canopy gaps and a larger number of snags compared with random trees. Vegetation clumps of 0.1 ha containing a minimum of 10 snags with a diameter at breast height (DBH) ≥ 10 cm should be maintained to preserve roosting habitat that is used by male Myotis bats in balsam fir – paper birch forests.