They have babies that are small enough to make pens. I also found that you can shrink a skin quite a bit with heat. I had a skin that was wrinkled so I had the idea to iron it to smooth it out. I laid out the skin and put a damp paper towel over it and as soon as the iron started warming up, not hot, I pressed the skin and it shrunk. The pattern looks better but it gets a little thicker also. I do it often because on the larger copperheads the patten is too big and you can see through the skin. I had a large rattlesnake and was able to put it on a slim pen with no problem.