Data from: Inconspicuous echolocation in hoary bats (Lasiurus cinereus)

Echolocation allows bats to occupy diverse nocturnal niches. Bats almost always use echolocation, even when other sensory stimuli are available to guide navigation. Here, using arrays of calibrated infrared cameras and ultrasonic microphones, we demonstrate that hoary bats (Lasiurus cinereus) use previously unknown echolocation behaviors that challenge our current understanding of echolocation. We describe a novel call type ("micro" calls) that has three orders of magnitude less sound energy than other bat calls used in open habitats. We also document bats flying close to microphones (< 3 m) without producing detectable echolocation calls. Acoustic modeling indicates that bats are not producing calls that exceed 70-75 dB at 0.1 m, a level that would have little or no known use for a bat flying in the open at speeds exceeding 7 m s-1. This indicates that hoary bats sometimes fly without echolocation. We speculate that bats reduce echolocation output to avoid eavesdropping by conspecifics during the mating season. These findings might partly explain why tens of thousands of hoary bats are killed at wind turbines each year. They also challenge the long-standing assumption that bats—model organisms for sensory specialization—are reliant on sonar for nocturnal navigation.Overview of audio and video dataExcel spreadsheet giving filenames of audio and video files in the archiveAudioVideoData.xlsxREADMERead me filing giving descriptions of files in data archive3D_Tracks3D bat trajectoriesAudioDetectionsTime points of call detections in audio filesMatlabCodeMatlab code for 3D track generation and audio processingScenesMatlab files giving scene information for each recording night. Data include the positions of cameras (camXYZr), microphones (micsr), and 3D calibration data (easyWandData).AudioFilesOriginal Audio FilesFunding provided by: National Science FoundationCrossref Funder Registry ID: http://dx.doi.org/10.13039/100000001Award Number: 125724