Sexing Runner Ducks

[karaokechick]

I noticed alot of people posting picture of chicks/young ducks saying this is a Drake ect.
Is there a way to sex them?

 

[92caddy]

How old are they? If they are young, you go by their sound, but if they are real young you cant go by that, if they are adults you lookk for the curl at the end of the tail, that will be drake and also by the sound. A hen will say quack and the male has a long deep soound, I cant explain it in a email.