How tolerant are dock eggs?

I think ducks like a lot of eggs to sit on . . . they can't count though, so you could always date the eggs with a pencil and take them out once there are enough older ones.  I am taking all my duck eggs right now - I'd like them to brood in March when it is a bit warmer.  So far they don't seem to be broody at all - but they do like laying. 

I think the eggs are okay, as long as the weather stays above freezing.  My duck eggs crack in freezing temperatures, and I can't imagine that they would still be fertile after freezing.  I think though that they would hatch better when the weather warms up a bit. 

It might depend on breed as well - some breeds of ducks are not known for being broody and others are - just like chickens.  I am planning on getting the incubator all set up in May if I don't see any broody ducks by then . . . but I'm like you - I'd prefer the momma duck does all the work!

Ducks vary, but if she is laying the eggs in a nest and covering them, she is probably collecting to set.  She won't set until she has the number that seems right to her.

I've never left duck eggs in the winter, but my goose laid 10 eggs, one every other day, so 20 days before she set. It was in the teens at night the whole time, and she hatched out 7 of those eggs.

I don't want ducklings when it is brutally cold, so I pick up all the duck eggs.  If the ducks get in the mood to set later in the season, I will allow them to collect a clutch.

It's different with geese because they are super parents with both goose and gander tending to the goslings' every blink.  Ducks aren't quite the quality of parents so I would rather not allow them to hatch until the weather is better.