Oh wow! ducks that sounds like fun!!! do they live in the same coop with the chickens? (clearly I know nothing about ducks)I know rats can be a problem, but I think its a less common problem with having chickens than non chicken people know about. Everybody I talked to about wanting to get them always said you get rats, and that was actually the reason it took me so long to get them. My mom didn't want us getting rats. So after I did some research I presented her with the findings on rats and chickens and if I remember correctly it usually isnt very likely you get rats as long as you follow some basic rules. I know when I talked with my aunt, who has chickens, she never mentioned anything about rats.
And it is almost time to need to order more. I need to make renovations to my coop first and then its a couple ducks for me next year.