We recently camped in Belleplain State Forest amid the “singing” of seventeen year cicadas, or in technical terms, Periodical Cicadas. My husband and I both thought the sound they created was much like an old Sci-Fi movie when flying saucers descended upon the earth. I’ve included a version here of the sound. You can read more information about the cicadas here: Periodical cicadas
The cicadas leave behind their eerie exoskeletons after emerging from the ground.
The ground is covered with holes from which the cicadas emerged.
You can hear their song on the video I took amid the trees of Belleplain.