Yup. Spring Peepers. We used to track them by flashlight when I was a teenager. As you got close they would stop peeping, but if you stood still a few minutes they would start again. Then you shined your light on the next place you thought they were peeping from and walked over to it (at which point they would stop peeping again). Eventually we could narrow it down to a 6" patch of ground and when he started peeping again, we could find him (they don't seem to be afraid of the flashlight, only nearby noises).
You're up.
