I wouldn't trust a full grown cat with tiny ducklings though I'd be worried the prey drive would kick in.@buff goose guy so sorry about your boy!
@dishrag my mallard girl was quite vocal anytime a car or person came up. She would also "talk" back at us if we said something to her, but other than that she was pretty quiet. On the cat note, Maggie thought she was a cat, and our cats just accepted her as their feathered overlord lol. It really just depends on the cat, usually they won't bother ducks or chickens.