NABat Monitoring Program
Hoping to gather more robust and scientifically valuable data, the VMN chapter launched a new bat monitoring project using large, stationary recording rigs at 13 locations throughout the county. The project aims to identify the species of bats that utilize Loudoun County and contribute to the United States Geological Service North American Bat Monitoring Project (NABat).
For at least the next decade a rich source of bat data will be produced for monitoring bat activity over time. Methods have been recently developed that allow bat echolocation calls to be recorded and then identified to species using commercially available equipment and software. VMN deployed thirteen stationary acoustic monitoring rigs around the county in the Spring and maintained the rigs throughout the year contributing over 500 hours to the project.
The rigs monitor four 100 km2 NABat grid locations and more than 450,000 recordings have been collected as of October 2022. These recordings demonstrate that nine species (see species list below) of bats were present in the county during the April-September time frame. Several cave dwelling species in North America have been negatively impacted by a fungal disease called White Nose Syndrome (WNS). Three of the species effected by WNS — Little Brown, Northern Long-eared, and Tri-colored bats — were observed in the county in 2022. Although further work will be required to confirm that these bats are present, this initial data suggests that Loudoun County is a home for some of North America’s struggling bats.