Don't fuss about the nests and eggs, just leave them to it. Some ducks will take up to 35 days to hatch, so just when you're getting edgy and thinking right that's it they're all duds, then out they pop, so just leave them to get on with it.
We put mum and ducklings in a coop for the first couple of weeks or so or crows, herons, whatever can get them easily as they are just little scraps at that age - mums tend to haul them around a bit too and they either can't keep up or get lost, ducks can't count remember - it's one, two, more than two, that's it, 2 eyes, 2 wings, what's the point in counting more than 2.
Don't feed chick crumbs, must be ducklings crumbs or you can kill them.
We use brown bread squished in milk which they love, bulk and protein.
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