Last weekend I got two new ducks (reportedly 1 & 2 yrs old). Since then, whenever I let my dog out back my khaki drake (6 months old) runs over and starts biting at the dog. The dog has been okay around the ducks & my 10 chickens up until now but I am worried that she might "turn" and bite the duck. When I have seen it happening I shoo the duck & try to reassure the dog but am worried a bit. Any suggestions?