I have 3 Cayuga's about 12 weeks old and 1 had a white splash on it's chest from the get go. The other two none. I'm prediciting from just watching them walk around, the draks hold their heads a little higher stretched out then the duck who seems to keep herself lower to the ground. I could be totally wrong, as this is the first time I have ever had ducks. Anyway...just my observation. Now I'm hoping that my crested Cayuga is a duck and not a drake. Need to even things up! I can't tell a dang thing from the tail feathers. Nothing curling up that I can see. I have heard, some deeper sounding quacks, but am never looking straight at them when I hear them, so who knows. I'm afraid I'm going to be in the same boat with the Blue Swedish my boyfriend brought home. The lady at the farm store told him she thought it was a drake. Darned if I can tell!