How much space??

I have 14 ducks and found out tonight my neighbor is giving me 4 more plus two full grown turkeys (for a total of 3 turkeys). How much space do I need for them in a pasture like setting? I do not want to crowd them. I know they have a certain acrage per cow suggestion and I was wondering how much for a duck. I also need room in thier pen for a small pond for them to swim in. I have close to 1/2 acer around the barn I can use. I would like to enclose it so they will stay in and the other animals stay out.

Here are some links from another board I am part of, I hope they help. I haven't gone through the links themselves, I picked them mainly by the titles, so if you don't find the answers to your questions let me know and I'll add more links for you.

4. Raising Waterfowl; A3311; 1994; Wisconsin; 20 pages.
http://cecommerce.uwex.edu/pdfs/A3311.PDF

5. Brooding and Rearing Ducklings and Goslings; G8920; 1993; Missouri; 3 pages.
http://muextension.missouri.edu/expl...try/g08920.htm

6. Raising Ducks; FS-01189; 1994; Minnesota; 3 pages.
http://www.extension.umn.edu/distrib...ms/DI1189.html

7. Management Program for Raising Breeder Duck Flocks; PS Facts #10; 1991; North Carolina State; 6 pages.
http://www.ces.ncsu.edu/depts/poulsc...ck_flocks.html

17. Turkey Care Practices; 1998; California; 29 pages.
http://www.vetmed.ucdavis.edu/vetext...eyCarePrax.pdf

18. Small Turkey Flock Management; NCR Extension Pub. #60; 19??; North Central Reg. Extension; 10 pages.
http://www.nc4h.org/teachers/enrichm...Management.pdf

10. The Home Flock; Pub. 268; 2000; Mississippi; 8 pages.
http://www.msstate.edu/dept/poultry/exthome.htm

6. Raising Birds on Pasture Resources; Sustainable Agriculture Research and Education.
http://www.sare.org/publications/poultry/resource.htm

18. Growing Small Farms – Pastured Poultry; North Carolina Cooperative Extension
http://chatham.ces.ncsu.edu/growings...ultrylist.html

Thank you. I will have hubby go thru them tonight. We didnt mean to get into the duck and turkey business but they kind of just fell in our laps. We were raising them on the halves. The lady we were getting the eggs from decided to get rid of her mallards, her turkeys and let us keep all the ducks we have raised. Now I got to get them a place to stay.