Presentation: 2025 ND EPSCoR Annual conference 

October 21, 2025, NDSU Memorial Union, Fargo, North Dakota

Acoustic Monitoring of Overwinter Activity and Spring Emergence of Bats in the North Dakota Badlands

In 2010-2013, a study conducted by Barhart & Gillam (2017), recorded bat winter activity using passive acoustic monitoring in Theodore Roosevelt National Park. This was the first study to actively record bat activity during the winter in North Dakota, suggesting bats are overwintering in the badlands. Since this study, Pseudogymnoascus destructans, the fungal pathogen responsible for White Nose Syndrome (WNS), has affected bat populations across the United States, resulting in mortality rates reaching upwards of 100%. Effective management of WNS requires a detailed understanding of bat presence and activity across seasons. To investigate post-WNS overwinter activity in North Dakota, bat calls will be recorded using Song Meter SM4BAF FS acoustic detectors. Detectors will be deployed at the same four sites used in the Barnhart and Gillam study (2017). Two additional control sites will be established to monitor seasonal patterns of decline in summer activity and spring emergence in areas where overwinting activity is not expected. Environmental variables, including ambient temperature, relative humidity, and barometric pressure will be monitored to assess their relationship to winter activity. Acoustic analyses will be conducted using Kaleidoscope Pro and SonoBat call analysis software. Recorded activity will be compared to the Barnhart & Gillam (2017) dataset, focusing on the timing of arousal, number of calls, and species detected. Findings will enhance the understanding of WNS impacts on overwintering insectivorous bats in North Dakota, providing wildlife managers with critical information for conservation and management measures. This project is funded by the National Science Foundation (award # 216605).