Baby ducks, how old to leave on their own.

Hey guys how old or large do my ducklings have to be to leave them on their own during the day please?
tks

Sorry Sebastian, but more information would be helpful!

1. What known predators are in the area? Where I live, we've got plenty of aerial predators and last year I lost a 4 week-old duckling to them and narrowly lost all three that were out despite having older ducks in the area. I would have thought they'd be safe by that age/size.

2. What sort of environment are you letting them out into? In the situation above, it was late summer and the grass was short and the birds tended to forage over a wide area. A smaller, food-rich zone with plenty of hiding spots would help prevent aerial predation - but may provide hiding spots for ground predators such as snakes, mink, or the neighbor's cat if those are risks in your area.

3. You call them "my ducklings" - does that mean that the ducklings are human reared, rather than mom reared? This increases your risk, as moms teach ducklings about dangers. I've currently got a Muscovy fostering 3 Khaki Campbell X ducklings and while watching them the other day, I saw them "peering at the sky" in response to noise - Mom taught them that, despite the language incompatibility! They were two weeks old when I first let them out with their foster mom, and I still only let them out while I'm in the field doing other tasks. It's been fun seeing how much farther she's been taking them as both the mom and ducklings have gained skill, strength and confidence.

4. How "left alone" do you mean? - Do you mean you're close but not watching? Do you mean you're off property? I've lost adult ducks to a mink attack in the middle of the afternoon which is uncommon. Small animals are the bottom of the food chain and just about everything is willing to consider them dinner. Where I live, I really need them to be fairly large before I'm prepared to leave them alone in our field.