Welcome to the love of call ducks!
@Pyxis can probably answer the breeding questions better than I can, but it is possible to keep 2 males and 2 females together. Most times, Calls with pick a mate, so your 2 pairs might mate up, or both males could possibly want the same female. So you’ll just have to try it, but be prepared to separate them.
For incubating eggs, they have a tendency to be broody, but there’s no guarantee. I have one that has never been broody, but ones younger than her that have. So that’s on the individual hens. Females usually start laying around 20 weeks or so. The eggs can be difficult to hatch in an incubator, and often require assisted hatching, so if you plan to incubate them, I’d suggest you read up on assisting.
Pretty birds you got.
We've been talking on Facebook
So I told you on there all your ducklings are probably going to be black bibbed and blue bibbed, unless your two hens happen to be split for e+ (mallard base) and aren't homozygous for E (extended black).
Looks like the males you have there are a snowy and a gray. So the ducklings from the gray will be black/blue bibbed, but split to mallard base, and the ducklings from the snowy would also be black/blue bibbed but split to mallard base and split to snowy, too. That means if you kept some to breed back, you could get gray, blue fawn, snowy, blue snowy, etc, from the ducklings.
