I have a 10 year old redfoot tortoise that seems to want to get away. This is not a new problem, but I'm wondering if anyone has any insights as to what causes her to want to do this. Of course, there are the obvious needs of "I'm in an enclosed area, I need to run wild", but I think that's not the case.
I have high plexiglass walls around the perimeter of her enclose, as before I had those (around 5 years ago), she was constantly using her front limbs to hoist herself up over the edge. Now she tries to climb the walls very persistently, rubbing up against them, and she flips herself over at times. She does this about once or twice a week, and it seems to pick up around the spring, but doesn't seem to be related to temperature (see below). She is monitored very well, so I don't worry as much about her lying there and getting too warm, but I'm more curious about why she's doing it than anything. It would be nice to break her of the habit, but she's not very trainable.
She has acceptable levels of heat (90s in the hot spot, high 70s around the periphery of the enclosure), she is well fed, has plenty of water (and a "pool" to soak in). She is not egg-bound, according to the vet, and has never laid eggs, so I think that rules out that she has an urge to mate. As I have mentioned in other questions, I have had plans for building her a larger enclosure in the works, so it's possible that she's feeling cramped, but the fact that her climbing is intermittent leads me to believe that there is some other issue that I'm missing.
What is prompting her to climb and is there any way for me to curb her urges to do so?