Acknowledgements We thank Brice Barefoot for his technical assistance and Rachel Willcutts for her help in the early stages of this work. We are grateful to Brian Pope and Tasha King at the Lubee Bat Conservancy for their expert assistance. Dr. Ramsburg's work was supported by NIH grants UC6 AI058607 and AI51445. Dr. Kepler's work was supported by discretionary funds provided by Duke University. No additional external funding was used. No funding source had any influence on the study design, on the collection, analysis, or interpretation of data, on the writing of the manuscript, or on the decision to submit the manuscript for publication.