We just had three ducklings hatch under a chicken. 2 Blue Swedish/Mallard and the third Mallard mix.
You should leave them in the incubator for like 24 hours to allow them to dry off and learn to use their little legs
Their left over yolk sac can feed the up to 3 days I believe. Maybe its only two.... You can probably feed and water them when you move them into the brooder. Temperature should be like 95 degrees F for like the first week and then decreasing each week thereafter. I believe they don't need humidity in the brooder. If they do then we have raised our ducks wrong!
-Have 4 Adult Ducks, 6 Ducklings (about 5-7 weeks old), 3 two day old ducklings <3-