Winter activity of Myotis septentrionalis: The role of temperature in controlling flights from hibernacula
Copyright (c) 2016 Cliff A. Lemen, Patricia W. Freeman, and Jeremy A. White
We acoustically monitored a small mine in southeastern Nebraska known to be a hibernaculum for the Northern Long-eared Myotis (Myotis septentrionalis) for two winters (2014-2015 and 2015-2016). Some M. septentrionalis emerged on nights with mild temperatures throughout both winters. There was an 89% probability of detecting this species when temperature at sunset was >5°C. Our results indicated that acoustical surveys outside mines or caves in winter, particularly on nights with mild temperatures, are an effective method of identifying hibernacula of M. septentrionalis and potentially other species without disturbing individuals by entering the hibernaculum or by netting individuals as they exit their winter quarters. However, the effectiveness of acoustical surveys is impacted by the certainty of identification of calls to species.