I have 10 male guinea and one guinea hen. Since they grew to almost full size the only distinct difference was that the hen makes a sound that is almost like a goose honking and she always feels the need to say something. We noticed early on that the one bird was different and thought that was...
I believe 1 - the females make a sound the makes cannot and they also lay eggs... So you basically have to stalk adult birds until you observe things then tag them or something?