Greetings, I have a four year old female Russian tortoise whom I have had for one year. She lives indoors and has a heat/UV lamp. I live in Southern Cailfornia and take her outside for sun when it is warm. Last year, I bought her from a man in our area and kept her inside during the winter. She did not hibernate, however, this year, she seems to want to burrow down and hibernate. For the last week, she has not wanted to eat and when I put her up to eat, she later burrows down. I am not sure if I should let her hibernate, and if so, how this is done. How long will she hibernate? How do I know if she is ready to do it, and if so, that she will be ok? Does anyone have some advice on the subject? Thank you so much!