I've committed over-duck. And I didn't intend to. Long story short, I started with two Rouen females. This spring I got 2 Pekins, 3 Rouens or Mallards (Barnyard combo), and 1 Cayuga (had 2 but one died ) Anyway, as they got bigger, I noticed they were all females. So, I saw an ad on Craigslist for ducklings at 5 for $8 and I got some Khaki Campbell x with Rouen, Swedish and Cayuga, hoping for a drake. Well, two of my young Rouens are getting green heads and one has a drake feather. I think I messed up. But, I have to admit, I like them a lot. They're cute, if messy, and watching them puts a smile on my face. And my llama adores them. He loves guarding them and watching them. So, when do the drake feathers show up? When do their voices change? Can you tell before 4-5 months?