At what age can you sex them by their sound/quaking?????

[GermanChick]

I have 3 Indian Runners and 1 Swedish Duck that are 3 weeks old. They are just starting to get their feathers in. At what age do they develop their quaking? From what I was reading this would be a lot earlier for sexing then waiting for the curly drake feather.
First year with ducks so everything is new ...

 

[mamdoe]

Wondering the same!
I have two 2 week old Pekin. I've suspected that one is a boy, because it's bigger than the other. The smaller of the two just stared making a quack sound..but the other is still chirping loudly.

 

[BooBoo45]

One of my Khaki females started to make a strange sound around 3 weeks old which eventually turned into a quack - she sounded almost asthmatic at one point or coming down with a cold! The others started to quack around 5 weeks. I was told that the first to hatch is always a drake by an old neighbour who kept ducks for as long as I can remember, not sure how much truth there is to that but my first to hatch did turn out to be the drake. I've five ladies and one drake - the drake is normally smaller too, they don't grow as fast as the girls. That stood the test too with my previous two ducklings, one hatched by the duck and the other was an incubator for a school project - both drakes.

Pip was quieter than the girls, didn't peep so much (unless I had food or water in my hands) and when he did, the peep wasn't as loud as the others. They are coming up to 7 weeks old now, I can't believe how quickly they've grown, but he's still the smallest.

 

[Going Quackers]

Well usually. 5-6wks that said sometimes as early as 3-4wks you can start to hear changes... size is not reliable ime with mallard derived, i had two buffs and one was bigger, they were both females. They eventually just evened out too.