I have a similar problem in that my guinea pig is eating the masking tape that is covering the sticky tape that is holding the coloplast together in the shape of a cage. The tape he's eating is paper based and non toxic so its not a major problem at the moment but its one i would realy like solving otherwise i'll have to go round the cage again sticking a load back on. The paper tape isn't holding the cage together, its simply there to stop him getting to the plastic tape underneath that might harm him. At the mo my only option is to chase him off it whenever i notice him doing it but he's a very cheeky piggie.