Female little brown bats require both building and natural roosts in a mountainous environment with short summers

Female little brown bats (Myotis lucifugus) in the Canadian Rocky Mountains rely on both buildings and natural roosts for survival, particularly in mountainous environments with short summers. Buildings are critical as they serve as the primary roost type during reproduction and provide thermal conditions that support overwinter survival. However, these colonies are unusually small, and bats show low fidelity to specific building roosts, suggesting inconsistent meeting of their needs. Natural roosts are also used, especially after colder nights, aiding in energy conservation through torpor. The study tracked 49 female bats over two summers in Banff, Yoho, and Kootenay National Parks, revealing delayed juvenile weaning, early hibernation onset, and low reproductive rates compared to more southern or non-mountainous areas. These findings highlight the importance of addressing the needs of both reproductive and nonreproductive individuals for population persistence.

Micalizzi, E. W., Forshner, S. A., Low, E. B., Johnston, B., Skarsgard, S. A., & Barclay, R. M. R. (2023). Female little brown bats require both building and natural roosts in a mountainous environment with short summers. Ecosphere, 14(12). Portico. https://doi.org/10.1002/ecs2.4731