sexing by voice + other ?'s

D Holderreads book on geese he wrote is like the duck version.

Until they are mature you wont really know unless you vent or DNA. Our African Gander stands much taller than the goose so visually you can pick them out. Our gander is more vocal, but again until mature you just have to wait. The vice change will happen for them all eventually. we are 3.5 monthsaway from our Africans rolling into breeding season again. They are the first here to start breeding and laying.

Gander right, goose left. I know I have better shots will dig for them

Some times the goose has a deeper voice.  Not always and not different enough to tell by voice unless you have both genders to listen to at the same time.

Sometimes the ganders are higher-headed when they walk around, but my #1 goose also walks around with her nose in the air, especially when she has goslings and is feeling protective.  The ganders, on the other hand often carry their heads down, unless they are on alert or feeling protective.

I have 2 geese (I know they are female) who never make any noise at all. So, I don't know what sort of voices they have.

Really, vent sexing or DNA sexing is what works the best.  Maybe during breeding season, the one on the nest is probably the female.  But ganders will sometimes set if they get the opportunity.

If you have Africans, when they are fully mature, the gander should have a larger knob than the goose.  Should.  Maybe.

Its not 100% here, since I have one female with a higher voice, but my female toulouse have very deep voices. Almost tuba-like, and they always say "Humph humph humph" with that really low pitch.   

I have a lot of birds out there, but most of the time I can tell who is outside the window just by the chatter.