I have a male bunny, he is around 5 years old. In the beginning I was a terrible owner and stuffed him in a small cage for hours a day. About a year ago I made him a small pen, about three feet by three feet. He has full range of that area and can even hop onto my bed with a step system I created. He has always chewed on the bars of his new pen, it’s quite annoying. He even tosses his pen around when he chews, like he is lifting it up to escape. I had ignored it and just made sure to put him in his smaller cage while I was away so he wouldn’t escape. I really wish I didn’t have to lock him up at all, but I can’t have him lifting up his pen to escape. His pen is about three feet high with no top on it, it’s just chicken wire in a square shape. Does anybody have any idea how to stop him from doing that? I want to keep the pen portable, so I don’t want to attach a bottom to it either.