I have a new half acre pond which I plan to stock soon. I would like to make my pond as productive as possible not only with regard to fish. I was thinking about getting some muscovy ducks. Are there any consequences, negative or otherwise, to adding ducks to a 1/2 acre fish pond?

I'm no duck expert, but from what I've read, I personally hope none show up on my pond. They will eat fish, as well as vegetation.

Check out this discussion:
http://www.backyardchickens.com/t/733559/considering-a-duck-pond-keepers-please-respond

Ducks will cause water cloudiness problems and add fertilizer for algae. I encourage wild ducks and thought about getting some domestic ones, but decided the drawbacks outweighed the advantages. I enjoy the migrating ducks and the occasional pair that sets up shop in our ponds and wetlands. I even leave the pair of geese that nests on our little island alone. The male keeps the rest of the geese away.

Not sure about ducks, but geese sure to help keep cattail infestations to a minimum.

By all means dont ,,,,,,,,,,the mess isnt worth it ,we had several and was tickled when the coyotes finaaly got them all

Just curious: Other than being unpleasant, what effect does the mess that ducks cause do to the pond? Is messiness or cloudiness bad for the fish in any way?

Well in my case
1 droppings on the dock and pond edges
2 Bad about mudding the shallows
3 muscoveys tend to over populate
4 compete with fish by eating fry, eggs, minnows and such
6 they learn quick what a fish feeder is

I can certainly keep their population in check (I love to eat duck and love their eggs too!). And the other things aren't a concern except for #4.

I wonder if I put a smaller pond for them on the opposite side of my property if they will still find their way back to my fish pond. Any thoughts?

Yea, they have an areal view, they'll find the fish.