I'd say hardware cloth, and yes it's expensive but when you took on the responsibility of your duckling [who is adorable by the way] then you took on the responsibility of making sure it is safe indoors and out. And believe me no matter where you live you put your duckling outside in something made of chicken wire you'll find out real fast about the predators you said you don't have.whoah.
Way to sugar coat it. (NOT)
(Jk)
What do I use then? (Cheapest optinoin please)

