I'm willing to get one started, but have a lot more experience with
chickens than I do with ducks, so hopefully others will add their input, too.
Ducks in
permaculture serve various functions: pest control; egg production; meat production; production of feathers and down for insulating bedding and clothing; manure production; cleaning ponds of unwanted weeds.
There are quite a few breeds of ducks, and most of them are useful in all of the above functions, but some are specialists in egg or meat production. Some are better foragers than others, but all are pretty good at picking up at least some of their own
feed much of the year, depending of course on the climate and the time of year.
Ducks have both advantages and disadvantages. Disadvantages include the messes they make with
water and mud; the management required to make sure they don't eat things you don't want eaten if you allow them in your garden; the protection that they need from predators (they are more vulnerable to predators than chickens because most breeds of domestic ducks don't fly well if at all); it takes longer to pluck ducks if you want the feathers and down.
Advantages include: they don't scratch the ground up like chickens do (this could also be in the disadvantages list if you want a patch scratched up); some breeds lay better than any chicken breed; their useful egg-laying years last longer than a chickens; duck eggs are more nutritious than chicken eggs and are also better for some kinds of baking; their meat is fatty -- an advantage if you are trying to raise all your own cooking fat; they love snails and slugs for dinner; they lay most of their eggs before eight o'clock in the morning, so if you want to be able to find the eggs, just keep them in their house until after eight; most ducks fly little if at all so are easy to keep fenced; ducks can be herded, which makes it a little easier to move them where you want them to go; they are much cold-hardier than chickens.
What other kinds of information do you want for the page?
Kathleen