Hi, a year & a half ago I brought my first red foot tortoise home & now a proud owner of 3. But the first was the only one I ever heard that actually made any audible sounds as she was growing up through the months & I thought this was normal behaviours, only one other person replied to my previous post by saying he/she has heard the exact same noise theirs made. It sounded like a very faint whirling electronic bird like chirping sound I initially thought was from my cellphone & whenever I bound with her at close range while petting her it occurs. Somebody suggested this could be the reaction from fear rather than content, but I don't entirely agree because it's been months passed since I had her & she is used to me & comes to me for protection when taken to the park of grass fields & hasn't pee when I picked her up. I had not heard any noise coming from the others & thus far months later, what are your experiences?