So my Grey Tree frogs have been trying out their chirpy voice(s). it is either only one or both. I cannot tell bc they stop chirping when i get close. We heard them chirp when the news was on and they were playing Taps at a funeral. They also chirped when i had the 70's station on and heard My Sharona. Then today i had that channel on again and Boston's More Than a Feeling was one and at the end of the song they chirped. I love it and hope that springtime will get them really chirpy.