If the wire bottomed cage is designed with Mandarin Ducks in mind, the wire would not be an issue... As "Dr Todd" mentioned, Call ducks have been forced to tolerate confinement through captive breeding, so they are able to withstand contant contact with wire in a small hutch enclosure.. Mandarins, being a wild duck, would need something a bit larger than a hutch, but since they spend most of their time perched up some place or swimming, the small amount of contact they have with wire would not prove to be an issue.