When a yukkuri's anyaru and/or mamumamu is blocked by something, preventing the yukkuri from peeing or pooping. It could be the following:
Sealed up by some sort of adhesive (i.e glue, tape) Covered by something which isn't easily removable when leave to their own devices (i.e a wet leaf, gravel) An item(s) is physically inserted into these orifices. (i.e a golf tee, sticks) The orifices are physically altered themselves (i.e using a soldering iron to seal the openings shut)