Well..I am picking up the new ducks tomorrow night. The seller is bringing me 3 Pekins (1 male, 2 females) and 3 Silver Appleyard (1 male, 2 females). I don't think my husband is very happy with me for trying to solve my problem by buying more ducks. Maybe my hope is outweighing my sense...
This brings me to figuring out how to best integrate everyone. As I already mentioned, my existing ducks will not use the duck house I have for them. It would be FAR too small for anything more than 2 ducks anyway. I have 2 existing coops. One is a "mobile" coop that is approximately 4' x 6' and sits about 12" off the ground with a ramp to the door. This coop is currently empty and inside a small fenced area (25' x 25'?) which can be isolated from the chicken yard. The coop itself has an automatic door and is predator proof. The fenced yard is NOT predator proof.
The 2nd existing coop is about 6' x 8' and is currently used by my 2 goats and 17 chickens. There is a ladder roost which takes up a lot of room so currently no extra space in here. This coop has to be manually locked each night. It is located inside a large fenced chicken yard which is approximately 125' x 25'. This is a guess but it is a big area. Again, the yard is not predator proof because it is not covered and the fence is only about 4 ft high.
I am in the process of building a 3rd new coop. It is located in the large chicken yard. It is 8' x 10" on a concrete slab with an automatic door. My intention is to move all my chickens (hopefully) into the new coop including 20 new baby chicks (currently 4 weeks old). I will have approx 25' - 30' of roost space in the new coop. The goats will NOT be allowed inside.
Soooo... If I am going to pen up the ducks (including trying to entice my existing ducks to join the new ones in the pen), it would seem my options are:
1. Put them all in in smaller fenced yard with the 4' x 6 coop.
2. Put them with the chickens and goats in the larger yard and allow them to decide which coop they will to go in (the one with the goats or the new one)
3. Move the mobile coop closer to the pond, retrofit the automatic door to work off solar power, and don't pen ANY of them into a yard. Might be able to put up a temporary fence for this option, just to get them used to going in the coop.
There's also the dilemma of the male - female balance. I will definitely have to cull at least one male. I'd really like to keep one Pekin male and the SA male both, if possible. That would bring me to 5 females with 2 males...
You are going to have to manually put them up every night at least until they are trained to go inside. If it were me I'd want them separate from your chickens.
I would say move the mobile pen down by the pond, but you're going to have a heck of a time getting them off the water and into the coop.
So, given the options you have I say I would put them in the fenced yard with their own coop away from the chickens.
Perhaps after a good long while of training you can utilize the automatic door but do not expect immediate results. My ducks will go into their little barns we have for them as soon as I get the mealworms out of an evening. But if I do not go out there to put them up before dark they will still stay outside. And it's been a year or more.
You may eventually get to the point where you could let them still go to the pond once they get comfortable and feel safe in their new fenced area. My ducks will come out of their fenced run and play in the yard but they always go back in their run where their food is. if I had a big pond for them to play in I don't know that they would.
If you decide to cull a drake I would choose one of the pekin if I were you. A pekin drake will most likely be heavier than a Apple Yard hen so having two fatties breeding the smaller girls could end up being a problem.
Congratulations on learning duck math!