Acoustic response of bats to the Brood X Periodical Cicada (Magicicada spp.) emergence

Periodical cicada emergences can positively affect vertebrate reproduction and breeding behavior, yet this response is not well studied for bats. We examined the acoustic response of 6 species/phonic groups of bats in 2021 to the emergence of Brood X periodical cicadas, along the Potomac River corridor, in Maryland and Virginia. Using a before-after-control-impact study design, we deployed ultrasonic acoustic detectors during the summers of 2020–2022 within and just outside the range of the cicada emergence to document bat response. We observed significantly more echolocation passes during the 2021 emergence and the year following within the range of cicadas, relative to changes among years outside of the periodical cicada range. Our study demonstrates that periodical cicadas may serve as a resource that causes an increase in bat activity.