The four ducklings I ordered were not sexed. I was hoping for four hens but I think I got a drake/hen pair for each breed. Any experts want to tell me their opinions? They are 5 weeks old and I am solely going off a difference in color darkness that I see. Also, one of the Runners one of the runners is extremely loud with its vocals ha. What do you think?
Spend as much time as you can just sitting with them maybe toss some mealworms out.
As for sexing at 5 weeks voice will most likely be the only way. Like CarleeAnn said females quack loud Drakes are raspy. Pick them up separately and walk away from the group. That may give you an idea if they get hysterical and start quacking.
You can't tell gender by looking at them.
At this age it's still early to be 100% sure based on voice, but you can attempt it and should know for sure in another 2-3 weeks (before 12 weeks, they can confuse you as males can be loud at first).
Males are quiet and raspy sounding. Females are loud and have a shrill "quack"