When do you start listening to quacks?

[Goat_Walker]

my mutt ducks are about a month old.
Most have a high pitched quack, while one or two have "croaks", the deeper quack. So are the higher pitched my males?

 

[headred]

I found that my bullfrog sounding ducks have ended up being the boys. The girls have a definite honk/quack. Mine are now 3 months, so maybe 1 to 2 months I could probably tell. I didn't want to admit to the boys, but thats how it turned out. I'm in the process of trading some drakes for some hens!