What is the maximum ratio of hens to drakes?

[quackingdom]

I really, really would rather have just one drake. It would make things so much easier for us. However, can one drake keep 18 females with a reasonable fertility rate, or will the rates be really low? We have Muscovies. Thanks.

 

[Free Spirit]

http://www.wikihow.com/Breed-Ducks

"Keep the correct ratio of drakes (males) to ducks. This will require a little research for the particular breed of your ducks. Heavy breeds such as the Muscovy and other meat production breeds will usually have a ratio of one drake to five ducks maximum. Lighter breeds such as the Khaki Campbell and Indian Runner can have a maximum ratio of around one drake to ten ducks."

 

[quackingdom]

Thank you. Then I guess I need a second drake.